Sets our main struct and passes it to the parent class.
Adds @widget to @container. Typically used for simple containers such as #GtkWindow, #GtkFrame, or #GtkButton; for more complicated layout containers such as #GtkBox or #GtkGrid, this function will pick default packing parameters that may not be correct. So consider functions such as gtk_box_pack_start() and gtk_grid_attach() as an alternative to gtk_container_add() in those cases. A widget may be added to only one container at a time; you can’t place the same widget inside two different containers.
Gets the value of a child property for @child and @container.
Gets the values of one or more child properties for @child and @container.
Emits a #GtkWidget::child-notify signal for the [child property][child-properties] @child_property on the child.
Emits a #GtkWidget::child-notify signal for the [child property][child-properties] specified by @pspec on the child.
Sets a child property for @child and @container.
Sets one or more child properties for @child and @container.
Returns the type of the children supported by the container.
Invokes @callback on each direct child of @container, including children that are considered “internal” (implementation details of the container). “Internal” children generally weren’t added by the user of the container, but were added by the container implementation itself.
Invokes @callback on each non-internal child of @container. See gtk_container_forall() for details on what constitutes an “internal” child. For all practical purposes, this function should iterate over precisely those child widgets that were added to the container by the application with explicit add() calls.
Retrieves the border width of the container. See gtk_container_set_border_width().
Returns the container’s non-internal children. See gtk_container_forall() for details on what constitutes an "internal" child.
Get the main Gtk struct
Retrieves the focus chain of the container, if one has been set explicitly. If no focus chain has been explicitly set, GTK+ computes the focus chain based on the positions of the children. In that case, GTK+ stores %NULL in @focusable_widgets and returns %FALSE.
Returns the current focus child widget inside @container. This is not the currently focused widget. That can be obtained by calling gtk_window_get_focus().
Retrieves the horizontal focus adjustment for the container. See gtk_container_set_focus_hadjustment ().
Retrieves the vertical focus adjustment for the container. See gtk_container_set_focus_vadjustment().
Returns a newly created widget path representing all the widget hierarchy from the toplevel down to and including @child.
Returns the resize mode for the container. See gtk_container_set_resize_mode ().
the main Gtk struct as a void*
When a container receives a call to the draw function, it must send synthetic #GtkWidget::draw calls to all children that don’t have their own #GdkWindows. This function provides a convenient way of doing this. A container, when it receives a call to its #GtkWidget::draw function, calls gtk_container_propagate_draw() once for each child, passing in the @cr the container received.
Removes @widget from @container. @widget must be inside @container. Note that @container will own a reference to @widget, and that this may be the last reference held; so removing a widget from its container can destroy that widget. If you want to use @widget again, you need to add a reference to it before removing it from a container, using g_object_ref(). If you don’t want to use @widget again it’s usually more efficient to simply destroy it directly using gtk_widget_destroy() since this will remove it from the container and help break any circular reference count cycles.
Removes all widgets from the container
Sets the border width of the container.
Sets a focus chain, overriding the one computed automatically by GTK+.
Sets, or unsets if @child is %NULL, the focused child of @container.
Hooks up an adjustment to focus handling in a container, so when a child of the container is focused, the adjustment is scrolled to show that widget. This function sets the horizontal alignment. See gtk_scrolled_window_get_hadjustment() for a typical way of obtaining the adjustment and gtk_container_set_focus_vadjustment() for setting the vertical adjustment.
Hooks up an adjustment to focus handling in a container, so when a child of the container is focused, the adjustment is scrolled to show that widget. This function sets the vertical alignment. See gtk_scrolled_window_get_vadjustment() for a typical way of obtaining the adjustment and gtk_container_set_focus_hadjustment() for setting the horizontal adjustment.
Sets the @reallocate_redraws flag of the container to the given value.
Sets the resize mode for the container.
Removes a focus chain explicitly set with gtk_container_set_focus_chain().
the main Gtk struct
the main Gtk struct
Get the main Gtk struct
the main Gtk struct as a void*
Sets the cursor.
Resets the cursor. don't know if this is implemented by GTK+. Seems that it's not
Modifies the font for this widget. This just calls modifyFont(new PgFontDescription(PgFontDescription.fromString(family ~ " " ~ size)));
Queues an animation frame update and adds a callback to be called before each frame. Until the tick callback is removed, it will be called frequently (usually at the frame rate of the output device or as quickly as the application can be repainted, whichever is slower). For this reason, is most suitable for handling graphics that change every frame or every few frames. The tick callback does not automatically imply a relayout or repaint. If you want a repaint or relayout, and aren't changing widget properties that would trigger that (for example, changing the text of a gtk.Label), then you will have to call queueResize() or queuDrawArea() yourself.
This signal is emitted when a widget is supposed to render itself. The @widget's top left corner must be painted at the origin of the passed in context and be sized to the values returned by gtk_widget_get_allocated_width() and gtk_widget_get_allocated_height().
This signal is emitted when a widget is supposed to render itself. The @widget's top left corner must be painted at the origin of the passed in context and be sized to the values returned by gtk_widget_get_allocated_width() and gtk_widget_get_allocated_height().
Obtains the current default reading direction. See gtk_widget_set_default_direction().
Returns the default style used by all widgets initially.
Cancels the effect of a previous call to gtk_widget_push_composite_child().
Makes all newly-created widgets as composite children until the corresponding gtk_widget_pop_composite_child() call.
Sets the default reading direction for widgets where the direction has not been explicitly set by gtk_widget_set_direction().
For widgets that can be “activated” (buttons, menu items, etc.) this function activates them. Activation is what happens when you press Enter on a widget during key navigation. If @widget isn't activatable, the function returns %FALSE.
Installs an accelerator for this @widget in @accel_group that causes @accel_signal to be emitted if the accelerator is activated. The @accel_group needs to be added to the widget’s toplevel via gtk_window_add_accel_group(), and the signal must be of type %G_SIGNAL_ACTION. Accelerators added through this function are not user changeable during runtime. If you want to support accelerators that can be changed by the user, use gtk_accel_map_add_entry() and gtk_widget_set_accel_path() or gtk_menu_item_set_accel_path() instead.
Adds the device events in the bitfield @events to the event mask for @widget. See gtk_widget_set_device_events() for details.
Adds the events in the bitfield @events to the event mask for @widget. See gtk_widget_set_events() and the [input handling overview][event-masks] for details.
Adds a widget to the list of mnemonic labels for this widget. (See gtk_widget_list_mnemonic_labels()). Note the list of mnemonic labels for the widget is cleared when the widget is destroyed, so the caller must make sure to update its internal state at this point as well, by using a connection to the #GtkWidget::destroy signal or a weak notifier.
Queues an animation frame update and adds a callback to be called before each frame. Until the tick callback is removed, it will be called frequently (usually at the frame rate of the output device or as quickly as the application can be repainted, whichever is slower). For this reason, is most suitable for handling graphics that change every frame or every few frames. The tick callback does not automatically imply a relayout or repaint. If you want a repaint or relayout, and aren’t changing widget properties that would trigger that (for example, changing the text of a #GtkLabel), then you will have to call gtk_widget_queue_resize() or gtk_widget_queue_draw_area() yourself.
Determines whether an accelerator that activates the signal identified by @signal_id can currently be activated. This is done by emitting the #GtkWidget::can-activate-accel signal on @widget; if the signal isn’t overridden by a handler or in a derived widget, then the default check is that the widget must be sensitive, and the widget and all its ancestors mapped.
This function is used by custom widget implementations; if you're writing an app, you’d use gtk_widget_grab_focus() to move the focus to a particular widget, and gtk_container_set_focus_chain() to change the focus tab order. So you may want to investigate those functions instead.
Emits a #GtkWidget::child-notify signal for the [child property][child-properties] @child_property on @widget.
Same as gtk_widget_path(), but always uses the name of a widget’s type, never uses a custom name set with gtk_widget_set_name().
Computes whether a container should give this widget extra space when possible. Containers should check this, rather than looking at gtk_widget_get_hexpand() or gtk_widget_get_vexpand().
Creates a new #PangoContext with the appropriate font map, font options, font description, and base direction for drawing text for this widget. See also gtk_widget_get_pango_context().
Creates a new #PangoLayout with the appropriate font map, font description, and base direction for drawing text for this widget.
Destroys a widget.
This function sets *@widget_pointer to %NULL if @widget_pointer != %NULL. It’s intended to be used as a callback connected to the “destroy” signal of a widget. You connect gtk_widget_destroyed() as a signal handler, and pass the address of your widget variable as user data. Then when the widget is destroyed, the variable will be set to %NULL. Useful for example to avoid multiple copies of the same dialog.
Returns %TRUE if @device has been shadowed by a GTK+ device grab on another widget, so it would stop sending events to @widget. This may be used in the #GtkWidget::grab-notify signal to check for specific devices. See gtk_device_grab_add().
This function is equivalent to gtk_drag_begin_with_coordinates(), passing -1, -1 as coordinates.
Initiates a drag on the source side. The function only needs to be used when the application is starting drags itself, and is not needed when gtk_drag_source_set() is used.
Checks to see if a mouse drag starting at (@start_x, @start_y) and ending at (@current_x, @current_y) has passed the GTK+ drag threshold, and thus should trigger the beginning of a drag-and-drop operation.
Add the image targets supported by #GtkSelectionData to the target list of the drag destination. The targets are added with @info = 0. If you need another value, use gtk_target_list_add_image_targets() and gtk_drag_dest_set_target_list().
Add the text targets supported by #GtkSelectionData to the target list of the drag destination. The targets are added with @info = 0. If you need another value, use gtk_target_list_add_text_targets() and gtk_drag_dest_set_target_list().
Add the URI targets supported by #GtkSelectionData to the target list of the drag destination. The targets are added with @info = 0. If you need another value, use gtk_target_list_add_uri_targets() and gtk_drag_dest_set_target_list().
Looks for a match between the supported targets of @context and the @dest_target_list, returning the first matching target, otherwise returning %GDK_NONE. @dest_target_list should usually be the return value from gtk_drag_dest_get_target_list(), but some widgets may have different valid targets for different parts of the widget; in that case, they will have to implement a drag_motion handler that passes the correct target list to this function.
Returns the list of targets this widget can accept from drag-and-drop.
Returns whether the widget has been configured to always emit #GtkWidget::drag-motion signals.
Sets a widget as a potential drop destination, and adds default behaviors.
Sets this widget as a proxy for drops to another window.
Sets the target types that this widget can accept from drag-and-drop. The widget must first be made into a drag destination with gtk_drag_dest_set().
Tells the widget to emit #GtkWidget::drag-motion and #GtkWidget::drag-leave events regardless of the targets and the %GTK_DEST_DEFAULT_MOTION flag.
Clears information about a drop destination set with gtk_drag_dest_set(). The widget will no longer receive notification of drags.
Gets the data associated with a drag. When the data is received or the retrieval fails, GTK+ will emit a #GtkWidget::drag-data-received signal. Failure of the retrieval is indicated by the length field of the @selection_data signal parameter being negative. However, when gtk_drag_get_data() is called implicitely because the %GTK_DEST_DEFAULT_DROP was set, then the widget will not receive notification of failed drops.
Highlights a widget as a currently hovered drop target. To end the highlight, call gtk_drag_unhighlight(). GTK+ calls this automatically if %GTK_DEST_DEFAULT_HIGHLIGHT is set.
Add the writable image targets supported by #GtkSelectionData to the target list of the drag source. The targets are added with @info = 0. If you need another value, use gtk_target_list_add_image_targets() and gtk_drag_source_set_target_list().
Add the text targets supported by #GtkSelectionData to the target list of the drag source. The targets are added with @info = 0. If you need another value, use gtk_target_list_add_text_targets() and gtk_drag_source_set_target_list().
Add the URI targets supported by #GtkSelectionData to the target list of the drag source. The targets are added with @info = 0. If you need another value, use gtk_target_list_add_uri_targets() and gtk_drag_source_set_target_list().
Gets the list of targets this widget can provide for drag-and-drop.
Sets up a widget so that GTK+ will start a drag operation when the user clicks and drags on the widget. The widget must have a window.
Sets the icon that will be used for drags from a particular source to @icon. See the docs for #GtkIconTheme for more details.
Sets the icon that will be used for drags from a particular source to a themed icon. See the docs for #GtkIconTheme for more details.
Sets the icon that will be used for drags from a particular widget from a #GdkPixbuf. GTK+ retains a reference for @pixbuf and will release it when it is no longer needed.
Sets the icon that will be used for drags from a particular source to a stock icon.
Changes the target types that this widget offers for drag-and-drop. The widget must first be made into a drag source with gtk_drag_source_set().
Undoes the effects of gtk_drag_source_set().
Removes a highlight set by gtk_drag_highlight() from a widget.
Draws @widget to @cr. The top left corner of the widget will be drawn to the currently set origin point of @cr.
Ensures that @widget has a style (@widget->style).
Notifies the user about an input-related error on this widget. If the #GtkSettings:gtk-error-bell setting is %TRUE, it calls gdk_window_beep(), otherwise it does nothing.
Rarely-used function. This function is used to emit the event signals on a widget (those signals should never be emitted without using this function to do so). If you want to synthesize an event though, don’t use this function; instead, use gtk_main_do_event() so the event will behave as if it were in the event queue. Don’t synthesize expose events; instead, use gdk_window_invalidate_rect() to invalidate a region of the window.
Stops emission of #GtkWidget::child-notify signals on @widget. The signals are queued until gtk_widget_thaw_child_notify() is called on @widget.
Returns the accessible object that describes the widget to an assistive technology.
Retrieves the #GActionGroup that was registered using @prefix. The resulting #GActionGroup may have been registered to @widget or any #GtkWidget in its ancestry.
Returns the baseline that has currently been allocated to @widget. This function is intended to be used when implementing handlers for the #GtkWidget::draw function, and when allocating child widgets in #GtkWidget::size_allocate.
Returns the height that has currently been allocated to @widget. This function is intended to be used when implementing handlers for the #GtkWidget::draw function.
Retrieves the widget’s allocated size.
Returns the width that has currently been allocated to @widget. This function is intended to be used when implementing handlers for the #GtkWidget::draw function.
Retrieves the widget’s allocation.
Gets the first ancestor of @widget with type @widget_type. For example, gtk_widget_get_ancestor (widget, GTK_TYPE_BOX) gets the first #GtkBox that’s an ancestor of @widget. No reference will be added to the returned widget; it should not be unreferenced. See note about checking for a toplevel #GtkWindow in the docs for gtk_widget_get_toplevel().
Determines whether the application intends to draw on the widget in an #GtkWidget::draw handler.
Determines whether @widget can be a default widget. See gtk_widget_set_can_default().
Determines whether @widget can own the input focus. See gtk_widget_set_can_focus().
This function is only for use in widget implementations. Obtains @widget->requisition, unless someone has forced a particular geometry on the widget (e.g. with gtk_widget_set_size_request()), in which case it returns that geometry instead of the widget's requisition.
Gets the value set with gtk_widget_set_child_visible(). If you feel a need to use this function, your code probably needs reorganization.
Retrieves the widget’s clip area.
Returns the clipboard object for the given selection to be used with @widget. @widget must have a #GdkDisplay associated with it, so must be attached to a toplevel window.
Obtains the composite name of a widget.
Returns whether @device can interact with @widget and its children. See gtk_widget_set_device_enabled().
Returns the events mask for the widget corresponding to an specific device. These are the events that the widget will receive when @device operates on it.
Gets the reading direction for a particular widget. See gtk_widget_set_direction().
Get the #GdkDisplay for the toplevel window associated with this widget. This function can only be called after the widget has been added to a widget hierarchy with a #GtkWindow at the top.
Determines whether the widget is double buffered.
Returns the event mask (see #GdkEventMask) for the widget. These are the events that the widget will receive.
Returns whether the widget should grab focus when it is clicked with the mouse. See gtk_widget_set_focus_on_click().
Gets the font map that has been set with gtk_widget_set_font_map().
Returns the #cairo_font_options_t used for Pango rendering. When not set, the defaults font options for the #GdkScreen will be used.
Obtains the frame clock for a widget. The frame clock is a global “ticker” that can be used to drive animations and repaints. The most common reason to get the frame clock is to call gdk_frame_clock_get_frame_time(), in order to get a time to use for animating. For example you might record the start of the animation with an initial value from gdk_frame_clock_get_frame_time(), and then update the animation by calling gdk_frame_clock_get_frame_time() again during each repaint.
Gets the value of the #GtkWidget:halign property.
Returns the current value of the has-tooltip property. See #GtkWidget:has-tooltip for more information.
Determines whether @widget has a #GdkWindow of its own. See gtk_widget_set_has_window().
Gets whether the widget would like any available extra horizontal space. When a user resizes a #GtkWindow, widgets with expand=TRUE generally receive the extra space. For example, a list or scrollable area or document in your window would often be set to expand.
Gets whether gtk_widget_set_hexpand() has been used to explicitly set the expand flag on this widget.
Whether the widget is mapped.
Gets the value of the #GtkWidget:margin-bottom property.
Gets the value of the #GtkWidget:margin-end property.
Gets the value of the #GtkWidget:margin-left property.
Gets the value of the #GtkWidget:margin-right property.
Gets the value of the #GtkWidget:margin-start property.
Gets the value of the #GtkWidget:margin-top property.
Returns the modifier mask the @widget’s windowing system backend uses for a particular purpose.
Returns the current modifier style for the widget. (As set by gtk_widget_modify_style().) If no style has previously set, a new #GtkRcStyle will be created with all values unset, and set as the modifier style for the widget. If you make changes to this rc style, you must call gtk_widget_modify_style(), passing in the returned rc style, to make sure that your changes take effect.
Retrieves the name of a widget. See gtk_widget_set_name() for the significance of widget names.
Returns the current value of the #GtkWidget:no-show-all property, which determines whether calls to gtk_widget_show_all() will affect this widget.
Fetches the requested opacity for this widget. See gtk_widget_set_opacity().
Gets a #PangoContext with the appropriate font map, font description, and base direction for this widget. Unlike the context returned by gtk_widget_create_pango_context(), this context is owned by the widget (it can be used until the screen for the widget changes or the widget is removed from its toplevel), and will be updated to match any changes to the widget’s attributes. This can be tracked by using the #GtkWidget::screen-changed signal on the widget.
Returns the parent container of @widget.
Gets @widget’s parent window, or %NULL if it does not have one.
Returns the #GtkWidgetPath representing @widget, if the widget is not connected to a toplevel widget, a partial path will be created.
Obtains the location of the mouse pointer in widget coordinates. Widget coordinates are a bit odd; for historical reasons, they are defined as @widget->window coordinates for widgets that return %TRUE for gtk_widget_get_has_window(); and are relative to @widget->allocation.x, @widget->allocation.y otherwise.
Retrieves a widget’s initial minimum and natural height.
Retrieves a widget’s minimum and natural height and the corresponding baselines if it would be given the specified @width, or the default height if @width is -1. The baselines may be -1 which means that no baseline is requested for this widget.
Retrieves a widget’s minimum and natural height if it would be given the specified @width.
Retrieves the minimum and natural size of a widget, taking into account the widget’s preference for height-for-width management.
Retrieves a widget’s initial minimum and natural width.
Retrieves a widget’s minimum and natural width if it would be given the specified @height.
Determines whether @widget is realized.
Determines whether @widget is always treated as the default widget within its toplevel when it has the focus, even if another widget is the default.
Gets whether the widget prefers a height-for-width layout or a width-for-height layout.
Retrieves the widget’s requisition.
Get the root window where this widget is located. This function can only be called after the widget has been added to a widget hierarchy with #GtkWindow at the top.
Retrieves the internal scale factor that maps from window coordinates to the actual device pixels. On traditional systems this is 1, on high density outputs, it can be a higher value (typically 2).
Get the #GdkScreen from the toplevel window associated with this widget. This function can only be called after the widget has been added to a widget hierarchy with a #GtkWindow at the top.
Returns the widget’s sensitivity (in the sense of returning the value that has been set using gtk_widget_set_sensitive()).
Gets the settings object holding the settings used for this widget.
Gets the size request that was explicitly set for the widget using gtk_widget_set_size_request(). A value of -1 stored in @width or @height indicates that that dimension has not been set explicitly and the natural requisition of the widget will be used instead. See gtk_widget_set_size_request(). To get the size a widget will actually request, call gtk_widget_get_preferred_size() instead of this function.
Returns the widget state as a flag set. It is worth mentioning that the effective %GTK_STATE_FLAG_INSENSITIVE state will be returned, that is, also based on parent insensitivity, even if @widget itself is sensitive.
Simply an accessor function that returns @widget->style.
Returns the style context associated to @widget. The returned object is guaranteed to be the same for the lifetime of @widget.
Returns %TRUE if @widget is multiple pointer aware. See gtk_widget_set_support_multidevice() for more information.
Fetch an object build from the template XML for @widget_type in this @widget instance.
Gets the contents of the tooltip for @widget.
Gets the contents of the tooltip for @widget.
Returns the #GtkWindow of the current tooltip. This can be the GtkWindow created by default, or the custom tooltip window set using gtk_widget_set_tooltip_window().
This function returns the topmost widget in the container hierarchy @widget is a part of. If @widget has no parent widgets, it will be returned as the topmost widget. No reference will be added to the returned widget; it should not be unreferenced.
Gets the value of the #GtkWidget:valign property.
Gets the value of the #GtkWidget:valign property, including %GTK_ALIGN_BASELINE.
Gets whether the widget would like any available extra vertical space.
Gets whether gtk_widget_set_vexpand() has been used to explicitly set the expand flag on this widget.
Determines whether the widget is visible. If you want to take into account whether the widget’s parent is also marked as visible, use gtk_widget_is_visible() instead.
Gets the visual that will be used to render @widget.
Returns the widget’s window if it is realized, %NULL otherwise
Makes @widget the current grabbed widget.
Causes @widget to become the default widget. @widget must be able to be a default widget; typically you would ensure this yourself by calling gtk_widget_set_can_default() with a %TRUE value. The default widget is activated when the user presses Enter in a window. Default widgets must be activatable, that is, gtk_widget_activate() should affect them. Note that #GtkEntry widgets require the “activates-default” property set to %TRUE before they activate the default widget when Enter is pressed and the #GtkEntry is focused.
Causes @widget to have the keyboard focus for the #GtkWindow it's inside. @widget must be a focusable widget, such as a #GtkEntry; something like #GtkFrame won’t work.
Removes the grab from the given widget.
Determines whether @widget is the current default widget within its toplevel. See gtk_widget_set_can_default().
Determines if the widget has the global input focus. See gtk_widget_is_focus() for the difference between having the global input focus, and only having the focus within a toplevel.
Determines whether the widget is currently grabbing events, so it is the only widget receiving input events (keyboard and mouse).
Determines if the widget style has been looked up through the rc mechanism.
Checks whether there is a #GdkScreen is associated with this widget. All toplevel widgets have an associated screen, and all widgets added into a hierarchy with a toplevel window at the top.
Determines if the widget should show a visible indication that it has the global input focus. This is a convenience function for use in ::draw handlers that takes into account whether focus indication should currently be shown in the toplevel window of @widget. See gtk_window_get_focus_visible() for more information about focus indication.
Reverses the effects of gtk_widget_show(), causing the widget to be hidden (invisible to the user).
Utility function; intended to be connected to the #GtkWidget::delete-event signal on a #GtkWindow. The function calls gtk_widget_hide() on its argument, then returns %TRUE. If connected to ::delete-event, the result is that clicking the close button for a window (on the window frame, top right corner usually) will hide but not destroy the window. By default, GTK+ destroys windows when ::delete-event is received.
Returns whether the widget is currently being destroyed. This information can sometimes be used to avoid doing unnecessary work.
Creates and initializes child widgets defined in templates. This function must be called in the instance initializer for any class which assigned itself a template using gtk_widget_class_set_template()
Sets an input shape for this widget’s GDK window. This allows for windows which react to mouse click in a nonrectangular region, see gdk_window_input_shape_combine_region() for more information.
Inserts @group into @widget. Children of @widget that implement #GtkActionable can then be associated with actions in @group by setting their “action-name” to @prefix.action-name.
Computes the intersection of a @widget’s area and @area, storing the intersection in @intersection, and returns %TRUE if there was an intersection. @intersection may be %NULL if you’re only interested in whether there was an intersection.
Determines whether @widget is somewhere inside @ancestor, possibly with intermediate containers.
Whether @widget can rely on having its alpha channel drawn correctly. On X11 this function returns whether a compositing manager is running for @widget’s screen.
Determines whether @widget can be drawn to. A widget can be drawn to if it is mapped and visible.
Determines if the widget is the focus widget within its toplevel. (This does not mean that the #GtkWidget:has-focus property is necessarily set; #GtkWidget:has-focus will only be set if the toplevel widget additionally has the global input focus.)
Returns the widget’s effective sensitivity, which means it is sensitive itself and also its parent widget is sensitive
Determines whether @widget is a toplevel widget.
Determines whether the widget and all its parents are marked as visible.
This function should be called whenever keyboard navigation within a single widget hits a boundary. The function emits the #GtkWidget::keynav-failed signal on the widget and its return value should be interpreted in a way similar to the return value of gtk_widget_child_focus():
Lists the closures used by @widget for accelerator group connections with gtk_accel_group_connect_by_path() or gtk_accel_group_connect(). The closures can be used to monitor accelerator changes on @widget, by connecting to the @GtkAccelGroup::accel-changed signal of the #GtkAccelGroup of a closure which can be found out with gtk_accel_group_from_accel_closure().
Retrieves a %NULL-terminated array of strings containing the prefixes of #GActionGroup's available to @widget.
Returns a newly allocated list of the widgets, normally labels, for which this widget is the target of a mnemonic (see for example, gtk_label_set_mnemonic_widget()).
This function is only for use in widget implementations. Causes a widget to be mapped if it isn’t already.
Emits the #GtkWidget::mnemonic-activate signal.
Sets the base color for a widget in a particular state. All other style values are left untouched. The base color is the background color used along with the text color (see gtk_widget_modify_text()) for widgets such as #GtkEntry and #GtkTextView. See also gtk_widget_modify_style().
Sets the background color for a widget in a particular state.
Sets the cursor color to use in a widget, overriding the #GtkWidget cursor-color and secondary-cursor-color style properties.
Sets the foreground color for a widget in a particular state.
Sets the font to use for a widget.
Modifies style values on the widget.
Sets the text color for a widget in a particular state.
Sets the background color to use for a widget.
Sets the color to use for a widget.
Sets the cursor color to use in a widget, overriding the cursor-color and secondary-cursor-color style properties. All other style values are left untouched. See also gtk_widget_modify_style().
Sets the font to use for a widget. All other style values are left untouched. See gtk_widget_override_color().
Sets a symbolic color for a widget.
Obtains the full path to @widget. The path is simply the name of a widget and all its parents in the container hierarchy, separated by periods. The name of a widget comes from gtk_widget_get_name(). Paths are used to apply styles to a widget in gtkrc configuration files. Widget names are the type of the widget by default (e.g. “GtkButton”) or can be set to an application-specific value with gtk_widget_set_name(). By setting the name of a widget, you allow users or theme authors to apply styles to that specific widget in their gtkrc file. @path_reversed_p fills in the path in reverse order, i.e. starting with @widget’s name instead of starting with the name of @widget’s outermost ancestor.
This function is only for use in widget implementations.
Mark @widget as needing to recompute its expand flags. Call this function when setting legacy expand child properties on the child of a container.
Equivalent to calling gtk_widget_queue_draw_area() for the entire area of a widget.
Convenience function that calls gtk_widget_queue_draw_region() on the region created from the given coordinates.
Invalidates the area of @widget defined by @region by calling gdk_window_invalidate_region() on the widget’s window and all its child windows. Once the main loop becomes idle (after the current batch of events has been processed, roughly), the window will receive expose events for the union of all regions that have been invalidated.
This function is only for use in widget implementations. Flags a widget to have its size renegotiated; should be called when a widget for some reason has a new size request. For example, when you change the text in a #GtkLabel, #GtkLabel queues a resize to ensure there’s enough space for the new text.
This function works like gtk_widget_queue_resize(), except that the widget is not invalidated.
Creates the GDK (windowing system) resources associated with a widget. For example, @widget->window will be created when a widget is realized. Normally realization happens implicitly; if you show a widget and all its parent containers, then the widget will be realized and mapped automatically.
Computes the intersection of a @widget’s area and @region, returning the intersection. The result may be empty, use cairo_region_is_empty() to check.
Registers a #GdkWindow with the widget and sets it up so that the widget receives events for it. Call gtk_widget_unregister_window() when destroying the window.
Removes an accelerator from @widget, previously installed with gtk_widget_add_accelerator().
Removes a widget from the list of mnemonic labels for this widget. (See gtk_widget_list_mnemonic_labels()). The widget must have previously been added to the list with gtk_widget_add_mnemonic_label().
Removes a tick callback previously registered with gtk_widget_add_tick_callback().
A convenience function that uses the theme settings for @widget to look up @stock_id and render it to a pixbuf. @stock_id should be a stock icon ID such as #GTK_STOCK_OPEN or #GTK_STOCK_OK. @size should be a size such as #GTK_ICON_SIZE_MENU. @detail should be a string that identifies the widget or code doing the rendering, so that theme engines can special-case rendering for that widget or code.
A convenience function that uses the theme engine and style settings for @widget to look up @stock_id and render it to a pixbuf. @stock_id should be a stock icon ID such as #GTK_STOCK_OPEN or #GTK_STOCK_OK. @size should be a size such as #GTK_ICON_SIZE_MENU.
Moves a widget from one #GtkContainer to another, handling reference count issues to avoid destroying the widget.
Reset the styles of @widget and all descendents, so when they are looked up again, they get the correct values for the currently loaded RC file settings.
Updates the style context of @widget and all descendants by updating its widget path. #GtkContainers may want to use this on a child when reordering it in a way that a different style might apply to it. See also gtk_container_get_path_for_child().
Very rarely-used function. This function is used to emit an expose event on a widget. This function is not normally used directly. The only time it is used is when propagating an expose event to a windowless child widget (gtk_widget_get_has_window() is %FALSE), and that is normally done using gtk_container_propagate_draw().
Sends the focus change @event to @widget
Given an accelerator group, @accel_group, and an accelerator path, @accel_path, sets up an accelerator in @accel_group so whenever the key binding that is defined for @accel_path is pressed, @widget will be activated. This removes any accelerators (for any accelerator group) installed by previous calls to gtk_widget_set_accel_path(). Associating accelerators with paths allows them to be modified by the user and the modifications to be saved for future use. (See gtk_accel_map_save().)
Sets the widget’s allocation. This should not be used directly, but from within a widget’s size_allocate method.
Sets whether the application intends to draw on the widget in an #GtkWidget::draw handler.
Specifies whether @widget can be a default widget. See gtk_widget_grab_default() for details about the meaning of “default”.
Specifies whether @widget can own the input focus. See gtk_widget_grab_focus() for actually setting the input focus on a widget.
Sets whether @widget should be mapped along with its when its parent is mapped and @widget has been shown with gtk_widget_show().
Sets the widget’s clip. This must not be used directly, but from within a widget’s size_allocate method. It must be called after gtk_widget_set_allocation() (or after chaining up to the parent class), because that function resets the clip.
Sets a widgets composite name. The widget must be a composite child of its parent; see gtk_widget_push_composite_child().
Enables or disables a #GdkDevice to interact with @widget and all its children.
Sets the device event mask (see #GdkEventMask) for a widget. The event mask determines which events a widget will receive from @device. Keep in mind that different widgets have different default event masks, and by changing the event mask you may disrupt a widget’s functionality, so be careful. This function must be called while a widget is unrealized. Consider gtk_widget_add_device_events() for widgets that are already realized, or if you want to preserve the existing event mask. This function can’t be used with windowless widgets (which return %FALSE from gtk_widget_get_has_window()); to get events on those widgets, place them inside a #GtkEventBox and receive events on the event box.
Sets the reading direction on a particular widget. This direction controls the primary direction for widgets containing text, and also the direction in which the children of a container are packed. The ability to set the direction is present in order so that correct localization into languages with right-to-left reading directions can be done. Generally, applications will let the default reading direction present, except for containers where the containers are arranged in an order that is explicitly visual rather than logical (such as buttons for text justification).
Widgets are double buffered by default; you can use this function to turn off the buffering. “Double buffered” simply means that gdk_window_begin_draw_frame() and gdk_window_end_draw_frame() are called automatically around expose events sent to the widget. gdk_window_begin_draw_frame() diverts all drawing to a widget's window to an offscreen buffer, and gdk_window_end_draw_frame() draws the buffer to the screen. The result is that users see the window update in one smooth step, and don’t see individual graphics primitives being rendered.
Sets the event mask (see #GdkEventMask) for a widget. The event mask determines which events a widget will receive. Keep in mind that different widgets have different default event masks, and by changing the event mask you may disrupt a widget’s functionality, so be careful. This function must be called while a widget is unrealized. Consider gtk_widget_add_events() for widgets that are already realized, or if you want to preserve the existing event mask. This function can’t be used with widgets that have no window. (See gtk_widget_get_has_window()). To get events on those widgets, place them inside a #GtkEventBox and receive events on the event box.
Sets whether the widget should grab focus when it is clicked with the mouse. Making mouse clicks not grab focus is useful in places like toolbars where you don’t want the keyboard focus removed from the main area of the application.
Sets the font map to use for Pango rendering. When not set, the widget will inherit the font map from its parent.
Sets the #cairo_font_options_t used for Pango rendering in this widget. When not set, the default font options for the #GdkScreen will be used.
Sets the horizontal alignment of @widget. See the #GtkWidget:halign property.
Sets the has-tooltip property on @widget to @has_tooltip. See #GtkWidget:has-tooltip for more information.
Specifies whether @widget has a #GdkWindow of its own. Note that all realized widgets have a non-%NULL “window” pointer (gtk_widget_get_window() never returns a %NULL window when a widget is realized), but for many of them it’s actually the #GdkWindow of one of its parent widgets. Widgets that do not create a %window for themselves in #GtkWidget::realize must announce this by calling this function with @has_window = %FALSE.
Sets whether the widget would like any available extra horizontal space. When a user resizes a #GtkWindow, widgets with expand=TRUE generally receive the extra space. For example, a list or scrollable area or document in your window would often be set to expand.
Sets whether the hexpand flag (see gtk_widget_get_hexpand()) will be used.
Marks the widget as being mapped.
Sets the bottom margin of @widget. See the #GtkWidget:margin-bottom property.
Sets the end margin of @widget. See the #GtkWidget:margin-end property.
Sets the left margin of @widget. See the #GtkWidget:margin-left property.
Sets the right margin of @widget. See the #GtkWidget:margin-right property.
Sets the start margin of @widget. See the #GtkWidget:margin-start property.
Sets the top margin of @widget. See the #GtkWidget:margin-top property.
Widgets can be named, which allows you to refer to them from a CSS file. You can apply a style to widgets with a particular name in the CSS file. See the documentation for the CSS syntax (on the same page as the docs for #GtkStyleContext).
Sets the #GtkWidget:no-show-all property, which determines whether calls to gtk_widget_show_all() will affect this widget.
Request the @widget to be rendered partially transparent, with opacity 0 being fully transparent and 1 fully opaque. (Opacity values are clamped to the [0,1] range.). This works on both toplevel widget, and child widgets, although there are some limitations:
This function is useful only when implementing subclasses of #GtkContainer. Sets the container as the parent of @widget, and takes care of some details such as updating the state and style of the child to reflect its new location. The opposite function is gtk_widget_unparent().
Sets a non default parent window for @widget.
Marks the widget as being realized. This function must only be called after all #GdkWindows for the @widget have been created and registered.
Specifies whether @widget will be treated as the default widget within its toplevel when it has the focus, even if another widget is the default.
Sets whether the entire widget is queued for drawing when its size allocation changes. By default, this setting is %TRUE and the entire widget is redrawn on every size change. If your widget leaves the upper left unchanged when made bigger, turning this setting off will improve performance.
Sets the sensitivity of a widget. A widget is sensitive if the user can interact with it. Insensitive widgets are “grayed out” and the user can’t interact with them. Insensitive widgets are known as “inactive”, “disabled”, or “ghosted” in some other toolkits.
Sets the minimum size of a widget; that is, the widget’s size request will be at least @width by @height. You can use this function to force a widget to be larger than it normally would be.
This function is for use in widget implementations. Turns on flag values in the current widget state (insensitive, prelighted, etc.).
Used to set the #GtkStyle for a widget (@widget->style). Since GTK 3, this function does nothing, the passed in style is ignored.
Enables or disables multiple pointer awareness. If this setting is %TRUE, @widget will start receiving multiple, per device enter/leave events. Note that if custom #GdkWindows are created in #GtkWidget::realize, gdk_window_set_support_multidevice() will have to be called manually on them.
Sets @markup as the contents of the tooltip, which is marked up with the [Pango text markup language]PangoMarkupFormat.
Sets @text as the contents of the tooltip. This function will take care of setting #GtkWidget:has-tooltip to %TRUE and of the default handler for the #GtkWidget::query-tooltip signal.
Replaces the default window used for displaying tooltips with @custom_window. GTK+ will take care of showing and hiding @custom_window at the right moment, to behave likewise as the default tooltip window. If @custom_window is %NULL, the default tooltip window will be used.
Sets the vertical alignment of @widget. See the #GtkWidget:valign property.
Sets whether the widget would like any available extra vertical space.
Sets whether the vexpand flag (see gtk_widget_get_vexpand()) will be used.
Sets the visibility state of @widget. Note that setting this to %TRUE doesn’t mean the widget is actually viewable, see gtk_widget_get_visible().
Sets the visual that should be used for by widget and its children for creating #GdkWindows. The visual must be on the same #GdkScreen as returned by gtk_widget_get_screen(), so handling the #GtkWidget::screen-changed signal is necessary.
Sets a widget’s window. This function should only be used in a widget’s #GtkWidget::realize implementation. The %window passed is usually either new window created with gdk_window_new(), or the window of its parent widget as returned by gtk_widget_get_parent_window().
Sets a shape for this widget’s GDK window. This allows for transparent windows etc., see gdk_window_shape_combine_region() for more information.
Flags a widget to be displayed. Any widget that isn’t shown will not appear on the screen. If you want to show all the widgets in a container, it’s easier to call gtk_widget_show_all() on the container, instead of individually showing the widgets.
Recursively shows a widget, and any child widgets (if the widget is a container).
Shows a widget. If the widget is an unmapped toplevel widget (i.e. a #GtkWindow that has not yet been shown), enter the main loop and wait for the window to actually be mapped. Be careful; because the main loop is running, anything can happen during this function.
This function is only used by #GtkContainer subclasses, to assign a size and position to their child widgets.
This function is only used by #GtkContainer subclasses, to assign a size, position and (optionally) baseline to their child widgets.
This function is typically used when implementing a #GtkContainer subclass. Obtains the preferred size of a widget. The container uses this information to arrange its child widgets and decide what size allocations to give them with gtk_widget_size_allocate().
This function attaches the widget’s #GtkStyle to the widget's #GdkWindow. It is a replacement for
Gets the value of a style property of @widget.
Non-vararg variant of gtk_widget_style_get(). Used primarily by language bindings.
Reverts the effect of a previous call to gtk_widget_freeze_child_notify(). This causes all queued #GtkWidget::child-notify signals on @widget to be emitted.
Translate coordinates relative to @src_widget’s allocation to coordinates relative to @dest_widget’s allocations. In order to perform this operation, both widgets must be realized, and must share a common toplevel.
Triggers a tooltip query on the display where the toplevel of @widget is located. See gtk_tooltip_trigger_tooltip_query() for more information.
This function is only for use in widget implementations. Causes a widget to be unmapped if it’s currently mapped.
This function is only for use in widget implementations. Should be called by implementations of the remove method on #GtkContainer, to dissociate a child from the container.
This function is only useful in widget implementations. Causes a widget to be unrealized (frees all GDK resources associated with the widget, such as @widget->window).
Unregisters a #GdkWindow from the widget that was previously set up with gtk_widget_register_window(). You need to call this when the window is no longer used by the widget, such as when you destroy it.
This function is for use in widget implementations. Turns off flag values for the current widget state (insensitive, prelighted, etc.). See gtk_widget_set_state_flags().
The ::button-press-event signal will be emitted when a button (typically from a mouse) is pressed.
The ::button-press-event signal will be emitted when a button (typically from a mouse) is pressed.
The ::button-release-event signal will be emitted when a button (typically from a mouse) is released.
The ::button-release-event signal will be emitted when a button (typically from a mouse) is released.
Determines whether an accelerator that activates the signal identified by @signal_id can currently be activated. This signal is present to allow applications and derived widgets to override the default #GtkWidget handling for determining whether an accelerator can be activated.
The ::child-notify signal is emitted for each [child property][child-properties] that has changed on an object. The signal's detail holds the property name.
The ::composited-changed signal is emitted when the composited status of @widgets screen changes. See gdk_screen_is_composited().
The ::configure-event signal will be emitted when the size, position or stacking of the @widget's window has changed.
The ::configure-event signal will be emitted when the size, position or stacking of the @widget's window has changed.
Emitted when a redirected window belonging to @widget gets drawn into. The region/area members of the event shows what area of the redirected drawable was drawn into.
Emitted when a redirected window belonging to @widget gets drawn into. The region/area members of the event shows what area of the redirected drawable was drawn into.
The ::delete-event signal is emitted if a user requests that a toplevel window is closed. The default handler for this signal destroys the window. Connecting gtk_widget_hide_on_delete() to this signal will cause the window to be hidden instead, so that it can later be shown again without reconstructing it.
Signals that all holders of a reference to the widget should release the reference that they hold. May result in finalization of the widget if all references are released.
The ::destroy-event signal is emitted when a #GdkWindow is destroyed. You rarely get this signal, because most widgets disconnect themselves from their window before they destroy it, so no widget owns the window at destroy time.
The ::direction-changed signal is emitted when the text direction of a widget changes.
The ::drag-begin signal is emitted on the drag source when a drag is started. A typical reason to connect to this signal is to set up a custom drag icon with e.g. gtk_drag_source_set_icon_pixbuf().
The ::drag-data-delete signal is emitted on the drag source when a drag with the action %GDK_ACTION_MOVE is successfully completed. The signal handler is responsible for deleting the data that has been dropped. What "delete" means depends on the context of the drag operation.
The ::drag-data-get signal is emitted on the drag source when the drop site requests the data which is dragged. It is the responsibility of the signal handler to fill @data with the data in the format which is indicated by @info. See gtk_selection_data_set() and gtk_selection_data_set_text().
The ::drag-data-received signal is emitted on the drop site when the dragged data has been received. If the data was received in order to determine whether the drop will be accepted, the handler is expected to call gdk_drag_status() and not finish the drag. If the data was received in response to a #GtkWidget::drag-drop signal (and this is the last target to be received), the handler for this signal is expected to process the received data and then call gtk_drag_finish(), setting the @success parameter depending on whether the data was processed successfully.
The ::drag-drop signal is emitted on the drop site when the user drops the data onto the widget. The signal handler must determine whether the cursor position is in a drop zone or not. If it is not in a drop zone, it returns %FALSE and no further processing is necessary. Otherwise, the handler returns %TRUE. In this case, the handler must ensure that gtk_drag_finish() is called to let the source know that the drop is done. The call to gtk_drag_finish() can be done either directly or in a #GtkWidget::drag-data-received handler which gets triggered by calling gtk_drag_get_data() to receive the data for one or more of the supported targets.
The ::drag-end signal is emitted on the drag source when a drag is finished. A typical reason to connect to this signal is to undo things done in #GtkWidget::drag-begin.
The ::drag-failed signal is emitted on the drag source when a drag has failed. The signal handler may hook custom code to handle a failed DnD operation based on the type of error, it returns %TRUE is the failure has been already handled (not showing the default "drag operation failed" animation), otherwise it returns %FALSE.
The ::drag-leave signal is emitted on the drop site when the cursor leaves the widget. A typical reason to connect to this signal is to undo things done in #GtkWidget::drag-motion, e.g. undo highlighting with gtk_drag_unhighlight().
The ::drag-motion signal is emitted on the drop site when the user moves the cursor over the widget during a drag. The signal handler must determine whether the cursor position is in a drop zone or not. If it is not in a drop zone, it returns %FALSE and no further processing is necessary. Otherwise, the handler returns %TRUE. In this case, the handler is responsible for providing the necessary information for displaying feedback to the user, by calling gdk_drag_status().
The ::enter-notify-event will be emitted when the pointer enters the @widget's window.
The ::enter-notify-event will be emitted when the pointer enters the @widget's window.
The GTK+ main loop will emit three signals for each GDK event delivered to a widget: one generic ::event signal, another, more specific, signal that matches the type of event delivered (e.g. #GtkWidget::key-press-event) and finally a generic #GtkWidget::event-after signal.
After the emission of the #GtkWidget::event signal and (optionally) the second more specific signal, ::event-after will be emitted regardless of the previous two signals handlers return values.
The ::focus-in-event signal will be emitted when the keyboard focus enters the @widget's window.
The ::focus-in-event signal will be emitted when the keyboard focus enters the @widget's window.
The ::focus-out-event signal will be emitted when the keyboard focus leaves the @widget's window.
The ::focus-out-event signal will be emitted when the keyboard focus leaves the @widget's window.
Emitted when a pointer or keyboard grab on a window belonging to @widget gets broken.
Emitted when a pointer or keyboard grab on a window belonging to @widget gets broken.
The ::grab-notify signal is emitted when a widget becomes shadowed by a GTK+ grab (not a pointer or keyboard grab) on another widget, or when it becomes unshadowed due to a grab being removed.
The ::hide signal is emitted when @widget is hidden, for example with gtk_widget_hide().
The ::hierarchy-changed signal is emitted when the anchored state of a widget changes. A widget is “anchored” when its toplevel ancestor is a #GtkWindow. This signal is emitted when a widget changes from un-anchored to anchored or vice-versa.
The ::key-press-event signal is emitted when a key is pressed. The signal emission will reoccur at the key-repeat rate when the key is kept pressed.
The ::key-press-event signal is emitted when a key is pressed. The signal emission will reoccur at the key-repeat rate when the key is kept pressed.
The ::key-release-event signal is emitted when a key is released.
The ::key-release-event signal is emitted when a key is released.
Gets emitted if keyboard navigation fails. See gtk_widget_keynav_failed() for details.
The ::leave-notify-event will be emitted when the pointer leaves the @widget's window.
The ::leave-notify-event will be emitted when the pointer leaves the @widget's window.
The ::map signal is emitted when @widget is going to be mapped, that is when the widget is visible (which is controlled with gtk_widget_set_visible()) and all its parents up to the toplevel widget are also visible. Once the map has occurred, #GtkWidget::map-event will be emitted.
The ::map-event signal will be emitted when the @widget's window is mapped. A window is mapped when it becomes visible on the screen.
The ::map-event signal will be emitted when the @widget's window is mapped. A window is mapped when it becomes visible on the screen.
The default handler for this signal activates @widget if @group_cycling is %FALSE, or just makes @widget grab focus if @group_cycling is %TRUE.
The ::motion-notify-event signal is emitted when the pointer moves over the widget's #GdkWindow.
The ::motion-notify-event signal is emitted when the pointer moves over the widget's #GdkWindow.
The ::parent-set signal is emitted when a new parent has been set on a widget.
This signal gets emitted whenever a widget should pop up a context menu. This usually happens through the standard key binding mechanism; by pressing a certain key while a widget is focused, the user can cause the widget to pop up a menu. For example, the #GtkEntry widget creates a menu with clipboard commands. See the [Popup Menu Migration Checklist][checklist-popup-menu] for an example of how to use this signal.
The ::property-notify-event signal will be emitted when a property on the @widget's window has been changed or deleted.
The ::property-notify-event signal will be emitted when a property on the @widget's window has been changed or deleted.
To receive this signal the #GdkWindow associated to the widget needs to enable the #GDK_PROXIMITY_IN_MASK mask.
To receive this signal the #GdkWindow associated to the widget needs to enable the #GDK_PROXIMITY_IN_MASK mask.
To receive this signal the #GdkWindow associated to the widget needs to enable the #GDK_PROXIMITY_OUT_MASK mask.
To receive this signal the #GdkWindow associated to the widget needs to enable the #GDK_PROXIMITY_OUT_MASK mask.
Emitted when #GtkWidget:has-tooltip is %TRUE and the hover timeout has expired with the cursor hovering "above" @widget; or emitted when @widget got focus in keyboard mode.
The ::realize signal is emitted when @widget is associated with a #GdkWindow, which means that gtk_widget_realize() has been called or the widget has been mapped (that is, it is going to be drawn).
The ::screen-changed signal gets emitted when the screen of a widget has changed.
The ::scroll-event signal is emitted when a button in the 4 to 7 range is pressed. Wheel mice are usually configured to generate button press events for buttons 4 and 5 when the wheel is turned.
The ::scroll-event signal is emitted when a button in the 4 to 7 range is pressed. Wheel mice are usually configured to generate button press events for buttons 4 and 5 when the wheel is turned.
The ::selection-clear-event signal will be emitted when the the @widget's window has lost ownership of a selection.
The ::selection-clear-event signal will be emitted when the the @widget's window has lost ownership of a selection.
The ::selection-request-event signal will be emitted when another client requests ownership of the selection owned by the @widget's window.
The ::selection-request-event signal will be emitted when another client requests ownership of the selection owned by the @widget's window.
The ::show signal is emitted when @widget is shown, for example with gtk_widget_show().
The ::state-changed signal is emitted when the widget state changes. See gtk_widget_get_state().
The ::state-flags-changed signal is emitted when the widget state changes, see gtk_widget_get_state_flags().
The ::style-set signal is emitted when a new style has been set on a widget. Note that style-modifying functions like gtk_widget_modify_base() also cause this signal to be emitted.
The ::style-updated signal is a convenience signal that is emitted when the #GtkStyleContext::changed signal is emitted on the @widget's associated #GtkStyleContext as returned by gtk_widget_get_style_context().
The ::unmap signal is emitted when @widget is going to be unmapped, which means that either it or any of its parents up to the toplevel widget have been set as hidden.
The ::unmap-event signal will be emitted when the @widget's window is unmapped. A window is unmapped when it becomes invisible on the screen.
The ::unmap-event signal will be emitted when the @widget's window is unmapped. A window is unmapped when it becomes invisible on the screen.
The ::unrealize signal is emitted when the #GdkWindow associated with @widget is destroyed, which means that gtk_widget_unrealize() has been called or the widget has been unmapped (that is, it is going to be hidden).
The ::visibility-notify-event will be emitted when the @widget's window is obscured or unobscured.
The ::visibility-notify-event will be emitted when the @widget's window is obscured or unobscured.
The ::window-state-event will be emitted when the state of the toplevel window associated to the @widget changes.
The ::window-state-event will be emitted when the state of the toplevel window associated to the @widget changes.
This function is supposed to be called in #GtkWidget::draw implementations for widgets that support multiple windows. @cr must be untransformed from invoking of the draw function. This function will return %TRUE if the contents of the given @window are supposed to be drawn and %FALSE otherwise. Note that when the drawing was not initiated by the windowing system this function will return %TRUE for all windows, so you need to draw the bottommost window first. Also, do not use “else if” statements to check which window should be drawn.
Transforms the given cairo context @cr that from @widget-relative coordinates to @window-relative coordinates. If the @widget’s window is not an ancestor of @window, no modification will be applied.
Distributes @extra_space to child @sizes by bringing smaller children up to natural size first.
A GTK+ user interface is constructed by nesting widgets inside widgets. Container widgets are the inner nodes in the resulting tree of widgets: they contain other widgets. So, for example, you might have a #GtkWindow containing a #GtkFrame containing a #GtkLabel. If you wanted an image instead of a textual label inside the frame, you might replace the #GtkLabel widget with a #GtkImage widget.
There are two major kinds of container widgets in GTK+. Both are subclasses of the abstract GtkContainer base class.
The first type of container widget has a single child widget and derives from #GtkBin. These containers are decorators, which add some kind of functionality to the child. For example, a #GtkButton makes its child into a clickable button; a #GtkFrame draws a frame around its child and a #GtkWindow places its child widget inside a top-level window.
The second type of container can have more than one child; its purpose is to manage layout. This means that these containers assign sizes and positions to their children. For example, a #GtkHBox arranges its children in a horizontal row, and a #GtkGrid arranges the widgets it contains in a two-dimensional grid.
For implementations of #GtkContainer the virtual method #GtkContainerClass.forall() is always required, since it's used for drawing and other internal operations on the children. If the #GtkContainer implementation expect to have non internal children it's needed to implement both #GtkContainerClass.add() and #GtkContainerClass.remove(). If the GtkContainer implementation has internal children, they should be added with gtk_widget_set_parent() on init() and removed with gtk_widget_unparent() in the #GtkWidgetClass.destroy() implementation. See more about implementing custom widgets at https://wiki.gnome.org/HowDoI/CustomWidgets
Height for width geometry management
GTK+ uses a height-for-width (and width-for-height) geometry management system. Height-for-width means that a widget can change how much vertical space it needs, depending on the amount of horizontal space that it is given (and similar for width-for-height).
There are some things to keep in mind when implementing container widgets that make use of GTK+’s height for width geometry management system. First, it’s important to note that a container must prioritize one of its dimensions, that is to say that a widget or container can only have a #GtkSizeRequestMode that is %GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH or %GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT. However, every widget and container must be able to respond to the APIs for both dimensions, i.e. even if a widget has a request mode that is height-for-width, it is possible that its parent will request its sizes using the width-for-height APIs.
To ensure that everything works properly, here are some guidelines to follow when implementing height-for-width (or width-for-height) containers.
Each request mode involves 2 virtual methods. Height-for-width apis run through gtk_widget_get_preferred_width() and then through gtk_widget_get_preferred_height_for_width(). When handling requests in the opposite #GtkSizeRequestMode it is important that every widget request at least enough space to display all of its content at all times.
When gtk_widget_get_preferred_height() is called on a container that is height-for-width, the container must return the height for its minimum width. This is easily achieved by simply calling the reverse apis implemented for itself as follows:
|[<!-- language="C" --> static void foo_container_get_preferred_height (GtkWidget *widget, gint *min_height, gint *nat_height) { if (i_am_in_height_for_width_mode) { gint min_width;
GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_width, NULL); GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget, min_width, min_height, nat_height); } else { ... many containers support both request modes, execute the real width-for-height request here by returning the collective heights of all widgets that are stacked vertically (or whatever is appropriate for this container) ... } } ]|
Similarly, when gtk_widget_get_preferred_width_for_height() is called for a container or widget that is height-for-width, it then only needs to return the base minimum width like so:
|[<!-- language="C" --> static void foo_container_get_preferred_width_for_height (GtkWidget *widget, gint for_height, gint *min_width, gint *nat_width) { if (i_am_in_height_for_width_mode) { GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, min_width, nat_width); } else { ... execute the real width-for-height request here based on the required width of the children collectively if the container were to be allocated the said height ... } } ]|
Height for width requests are generally implemented in terms of a virtual allocation of widgets in the input orientation. Assuming an height-for-width request mode, a container would implement the get_preferred_height_for_width() virtual function by first calling gtk_widget_get_preferred_width() for each of its children.
For each potential group of children that are lined up horizontally, the values returned by gtk_widget_get_preferred_width() should be collected in an array of #GtkRequestedSize structures. Any child spacing should be removed from the input @for_width and then the collective size should be allocated using the gtk_distribute_natural_allocation() convenience function.
The container will then move on to request the preferred height for each child by using gtk_widget_get_preferred_height_for_width() and using the sizes stored in the #GtkRequestedSize array.
To allocate a height-for-width container, it’s again important to consider that a container must prioritize one dimension over the other. So if a container is a height-for-width container it must first allocate all widgets horizontally using a #GtkRequestedSize array and gtk_distribute_natural_allocation() and then add any extra space (if and where appropriate) for the widget to expand.
After adding all the expand space, the container assumes it was allocated sufficient height to fit all of its content. At this time, the container must use the total horizontal sizes of each widget to request the height-for-width of each of its children and store the requests in a #GtkRequestedSize array for any widgets that stack vertically (for tabular containers this can be generalized into the heights and widths of rows and columns). The vertical space must then again be distributed using gtk_distribute_natural_allocation() while this time considering the allocated height of the widget minus any vertical spacing that the container adds. Then vertical expand space should be added where appropriate and available and the container should go on to actually allocating the child widgets.
See [GtkWidget’s geometry management section][geometry-management] to learn more about implementing height-for-width geometry management for widgets.
Child properties
GtkContainer introduces child properties. These are object properties that are not specific to either the container or the contained widget, but rather to their relation. Typical examples of child properties are the position or pack-type of a widget which is contained in a #GtkBox.
Use gtk_container_class_install_child_property() to install child properties for a container class and gtk_container_class_find_child_property() or gtk_container_class_list_child_properties() to get information about existing child properties.
To set the value of a child property, use gtk_container_child_set_property(), gtk_container_child_set() or gtk_container_child_set_valist(). To obtain the value of a child property, use gtk_container_child_get_property(), gtk_container_child_get() or gtk_container_child_get_valist(). To emit notification about child property changes, use gtk_widget_child_notify().
GtkContainer as GtkBuildable
The GtkContainer implementation of the GtkBuildable interface supports a <packing> element for children, which can contain multiple <property> elements that specify child properties for the child.
Since 2.16, child properties can also be marked as translatable using the same “translatable”, “comments” and “context” attributes that are used for regular properties.
Since 3.16, containers can have a <focus-chain> element containing multiple <widget> elements, one for each child that should be added to the focus chain. The ”name” attribute gives the id of the widget.
An example of these properties in UI definitions: |[ <object class="GtkBox"> <child> <object class="GtkEntry" id="entry1"/> <packing> <property name="pack-type">start</property> </packing> </child> <child> <object class="GtkEntry" id="entry2"/> </child> <focus-chain> <widget name="entry1"/> <widget name="entry2"/> </focus-chain> </object> ]|