In addition to a single pointer and keyboard for user interface input, GDK contains support for a variety of input devices, including graphics tablets, touchscreens and multiple pointers/keyboards interacting simultaneously with the user interface. Such input devices often have additional features, such as sub-pixel positioning information and additional device-dependent information.
In order to query the device hierarchy and be aware of changes in the device hierarchy (such as virtual devices being created or removed, or physical devices being plugged or unplugged), GDK provides gdk.DeviceManager
By default, and if the platform supports it, GDK is aware of multiple keyboard/pointer pairs and multitouch devices. This behavior can be changed by calling gdk_disable_multidevice() before Display.open. There should rarely be a need to do that though, since GDK defaults to a compatibility mode in which it will emit just one enter/leave event pair for all devices on a window. To enable per-device enter/leave events and other multi-pointer interaction features, Window.setSupportMultidevice must be called on gdk.Windows (or Widget.setSupportMultidevice on widgets). window. See the Window.setSupportMultidevice documentation for more information.
On X11, multi-device support is implemented through XInput 2. Unless gdk_disable_multidevice() is called, the XInput 2 gdk.DeviceManager implementation will be used as the input source. Otherwise either the core or XInput 1 implementations will be used.
For simple applications that don’t have any special interest in input devices, the so-called “client pointer” provides a reasonable approximation to a simple setup with a single pointer and keyboard. The device that has been set as the client pointer can be accessed via Device.managerGetClientPointer.
Conceptually, in multidevice mode there are 2 device types. Virtual devices (or master devices) are represented by the pointer cursors and keyboard foci that are seen on the screen. Physical devices (or slave devices) represent the hardware that is controlling the virtual devices, and thus have no visible cursor on the screen.
Virtual devices are always paired, so there is a keyboard device for every pointer device. Associations between devices may be inspected through Device.getAssociatedDevice.
There may be several virtual devices, and several physical devices could be controlling each of these virtual devices. Physical devices may also be “floating”, which means they are not attached to any virtual device.
|[ carlossacarino:~$ xinput list ⎡ Virtual core pointer id=2 [master pointer (3)] ⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)] ⎜ ↳ Wacom ISDv4 E6 Pen stylus id=10 [slave pointer (2)] ⎜ ↳ Wacom ISDv4 E6 Finger touch id=11 [slave pointer (2)] ⎜ ↳ SynPS/2 Synaptics TouchPad id=13 [slave pointer (2)] ⎜ ↳ TPPS/2 IBM TrackPoint id=14 [slave pointer (2)] ⎜ ↳ Wacom ISDv4 E6 Pen eraser id=16 [slave pointer (2)] ⎣ Virtual core keyboard id=3 [master keyboard (2)] ↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)] ↳ Power Button id=6 [slave keyboard (3)] ↳ Video Bus id=7 [slave keyboard (3)] ↳ Sleep Button id=8 [slave keyboard (3)] ↳ Integrated Camera id=9 [slave keyboard (3)] ↳ AT Translated Set 2 keyboard id=12 [slave keyboard (3)] ↳ ThinkPad Extra Buttons id=15 [slave keyboard (3)]
By default, GDK will automatically listen for events coming from all master devices, setting the [gdk.Device.Device|gdk.Device] for all events coming from input devices. Events containing device information are [GDK_MOTION_NOTIFY|GDK_MOTION_NOTIFY], [GDK_BUTTON_PRESS|GDK_BUTTON_PRESS], [GDK_2BUTTON_PRESS|GDK_2BUTTON_PRESS], [GDK_3BUTTON_PRESS|GDK_3BUTTON_PRESS], [GDK_BUTTON_RELEASE|GDK_BUTTON_RELEASE], [GDK_SCROLL|GDK_SCROLL], [GDK_KEY_PRESS|GDK_KEY_PRESS], [GDK_KEY_RELEASE|GDK_KEY_RELEASE], [GDK_ENTER_NOTIFY|GDK_ENTER_NOTIFY], [GDK_LEAVE_NOTIFY|GDK_LEAVE_NOTIFY], [GDK_FOCUS_CHANGE|GDK_FOCUS_CHANGE], [GDK_PROXIMITY_IN|GDK_PROXIMITY_IN], [GDK_PROXIMITY_OUT|GDK_PROXIMITY_OUT], [GDK_DRAG_ENTER|GDK_DRAG_ENTER], [GDK_DRAG_LEAVE|GDK_DRAG_LEAVE], [GDK_DRAG_MOTION|GDK_DRAG_MOTION], [GDK_DRAG_STATUS|GDK_DRAG_STATUS], [GDK_DROP_START|GDK_DROP_START], [GDK_DROP_FINISHED|GDK_DROP_FINISHED] and [GDK_GRAB_BROKEN|GDK_GRAB_BROKEN] When dealing with an event on a master device, it is possible to get the source (slave) device that the event originated from via [gdk.Event.Event.getSourceDevice|Event.getSourceDevice]. On a standard session, all physical devices are connected by default to the "Virtual Core Pointer/Keyboard" master devices, hence routing all events through these. This behavior is only modified by device grabs, where the slave device is temporarily detached for as long as the grab is held, and more permanently by user modifications to the device hierarchy. On certain application specific setups, it may make sense to detach a physical device from its master pointer, and mapping it to an specific window. This can be achieved by the combination of [gdk.Device.Device.grab|Device.grab] and [gdk.Device.Device.setMode|Device.setMode]. In order to listen for events coming from devices other than a virtual device, [gdk.Window.Window.setDeviceEvents|Window.setDeviceEvents] must be called. Generally, this function can be used to modify the event mask for any given device. Input devices may also provide additional information besides X/Y. For example, graphics tablets may also provide pressure and X/Y tilt information. This information is device-dependent, and may be queried through [gdk.Device.Device.getAxis|Device.getAxis]. In multidevice mode, virtual devices will change axes in order to always represent the physical device that is routing events through it. Whenever the physical device changes, the [gdk.Device.Device.getNAxes|n-axes] property will be notified, and [gdk.Device.Device.listAxes|Device.listAxes] will return the new device axes. Devices may also have associated “keys” or macro buttons. Such keys can be globally set to map into normal X keyboard events. The mapping is set using [gdk.Device.Device.setKey|Device.setKey]. In GTK+ 3.20, a new [gdk.Seat.Seat|gdk.Seat] object has been introduced that supersedes [gdk.DeviceManager.DeviceManager|gdk.DeviceManager] and should be preferred in newly written code.
Sets our main struct and passes it to the parent class.
The ::device-added signal is emitted either when a new master pointer is created, or when a slave (Hardware) input device is plugged in.
The ::device-changed signal is emitted whenever a device has changed in the hierarchy, either slave devices being disconnected from their master device or connected to another one, or master devices being added or removed a slave device.
The ::device-removed signal is emitted either when a master pointer is removed, or when a slave (Hardware) input device is unplugged.
Returns the client pointer, that is, the master pointer that acts as the core pointer for this application. In X11, window managers may change this depending on the interaction pattern under the presence of several pointers.
Get the main Gtk struct
Gets the gdk.Display associated to device_manager.
the main Gtk struct as a void*
Returns the list of devices of type type currently attached to device_manager.
Disables multidevice support in GDK. This call must happen prior to Display.open, gtk_init(), gtk_init_with_args() or gtk_init_check() in order to take effect.
the main Gtk struct
the main Gtk struct
Get the main Gtk struct
the main Gtk struct as a void*
Gets a D Object from the objects table of associations.
The notify signal is emitted on an object when one of its properties has been changed. Note that getting this signal doesn't guarantee that the value of the property has actually changed, it may also be emitted when the setter for the property is called to reinstate the previous value.
Find the gobject.ParamSpec with the given name for an interface. Generally, the interface vtable passed in as g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().
Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created gobject.ParamSpec, but normally ObjectClass.overrideProperty will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.
Lists the properties of an interface.Generally, the interface vtable passed in as g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().
Increases the reference count of the object by one and sets a callback to be called when all other references to the object are dropped, or when this is already the last reference to the object and another reference is established.
Adds a weak reference from weak_pointer to object to indicate that the pointer located at weak_pointer_location is only valid during the lifetime of object. When the object is finalized, weak_pointer will be set to NULL.
Creates a binding between source_property on source and target_property on target. Whenever the source_property is changed the target_property is updated using the same value. For instance:
Complete version of g_object_bind_property().
Creates a binding between source_property on source and target_property on target, allowing you to set the transformation functions to be used by the binding.
This is a variant of g_object_get_data() which returns a 'duplicate' of the value. dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.
This is a variant of g_object_get_qdata() which returns a 'duplicate' of the value. dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.
Increases the freeze count on object. If the freeze count is non-zero, the emission of "notify" signals on object is stopped. The signals are queued until the freeze count is decreased to zero. Duplicate notifications are squashed so that at most one notify signal is emitted for each property modified while the object is frozen.
Gets a named field from the objects table of associations (see g_object_set_data()).
Gets a property of an object. value must have been initialized to the expected type of the property (or a type to which the expected type can be transformed) using Value.init.
This function gets back user data pointers stored via g_object_set_qdata().
Gets properties of an object.
Gets n_properties properties for an object. Obtained properties will be set to values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.
Checks whether object has a floating[floating-ref] reference.
Emits a "notify" signal for the property property_name on object.
Emits a "notify" signal for the property specified by pspec on object.
Increases the reference count of object.
Increase the reference count of object, and possibly remove the floating[floating-ref] reference, if object has a floating reference.
Removes a reference added with g_object_add_toggle_ref(). The reference count of the object is decreased by one.
Removes a weak reference from object that was previously added using g_object_add_weak_pointer(). The weak_pointer_location has to match the one used with g_object_add_weak_pointer().
Compares the user data for the key key on object with oldval, and if they are the same, replaces oldval with newval.
Compares the user data for the key quark on object with oldval, and if they are the same, replaces oldval with newval.
Releases all references to other objects. This can be used to break reference cycles.
Each object carries around a table of associations from strings to pointers. This function lets you set an association.
Like g_object_set_data() except it adds notification for when the association is destroyed, either by setting it to a different value or when the object is destroyed.
Sets a property on an object.
This sets an opaque, named pointer on an object. The name is specified through a GQuark (retrived e.g. via g_quark_from_static_string()), and the pointer can be gotten back from the object with g_object_get_qdata() until the object is finalized. Setting a previously set user data pointer, overrides (frees) the old pointer set, using NULL as pointer essentially removes the data stored.
This function works like g_object_set_qdata(), but in addition, a void (*destroy) (gpointer) function may be specified which is called with data as argument when the object is finalized, or the data is being overwritten by a call to g_object_set_qdata() with the same quark.
Sets properties on an object.
Sets n_properties properties for an object. Properties to be set will be taken from values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
This function gets back user data pointers stored via g_object_set_qdata() and removes the data from object without invoking its destroy() function (if any was set). Usually, calling this function is only required to update user data pointers with a destroy notifier, for example:
Reverts the effect of a previous call to g_object_freeze_notify(). The freeze count is decreased on object and when it reaches zero, queued "notify" signals are emitted.
Decreases the reference count of object. When its reference count drops to 0, the object is finalized (i.e. its memory is freed).
This function essentially limits the life time of the closure to the life time of the object. That is, when the object is finalized, the closure is invalidated by calling Closure.invalidate on it, in order to prevent invocations of the closure with a finalized (nonexisting) object. Also, g_object_ref() and g_object_unref() are added as marshal guards to the closure, to ensure that an extra reference count is held on object during invocation of the closure. Usually, this function will be called on closures that use this object as closure data.
Adds a weak reference callback to an object. Weak references are used for notification when an object is finalized. They are called "weak references" because they allow you to safely hold a pointer to an object without calling g_object_ref() (g_object_ref() adds a strong reference, that is, forces the object to stay alive).
Removes a weak reference callback to an object.
Clears a reference to a GObject