Sets our main struct and passes it to the parent class
Creates a new source buffer.
Creates a new source buffer using the highlighting patterns in language. This is equivalent to creating a new source buffer with a new tag table and then calling gtk_source_buffer_set_language().
Sets iter to a valid iterator pointing to the matching bracket if state is GTK_SOURCE_BRACKET_MATCH_FOUND. Otherwise iter is meaningless. Since 2.12
The ::source_mark_updated signal is emitted each time a mark is added to, moved or removed from the buffer.
See Also GtkTextBuffer, GtkSourceView
Moves iter to the position of the previous GtkSourceMark of the given category. Returns TRUE if iter was moved. If category is NULL, the previous source mark can be of any category. Since 2.2
Marks the beginning of a not undoable action on the buffer, disabling the undo manager. Typically you would call this function before initially setting the contents of the buffer (e.g. when loading a file in a text editor). You may nest gtk_source_buffer_begin_not_undoable_action() / gtk_source_buffer_end_not_undoable_action() blocks.
Determines whether a source buffer can redo the last action (i.e. if the last operation was an undo).
Determines whether a source buffer can undo the last action.
Creates a source mark in the buffer of category category. A source mark is a GtkTextMark but organised into categories. Depending on the category a pixbuf can be specified that will be displayed along the line of the mark. Like a GtkTextMark, a GtkSourceMark can be anonymous if the passed name is NULL. Also, the buffer owns the marks so you shouldn't unreference it. Marks always have left gravity and are moved to the beginning of the line when the user deletes the line they were in. Typical uses for a source mark are bookmarks, breakpoints, current executing instruction indication in a source file, etc.. Since 2.2
Marks the end of a not undoable action on the buffer. When the last not undoable block is closed through the call to this function, the list of undo actions is cleared and the undo manager is re-enabled.
Forces buffer to analyze and highlight the given area synchronously. Note This is a potentially slow operation and should be used only when you need to make sure that some text not currently visible is highlighted, for instance before printing.
Moves iter to the position of the next GtkSourceMark of the given category. Returns TRUE if iter was moved. If category is NULL, the next source mark can be of any category. Since 2.2
Get all defined context classes at iter. See the GtkSourceBuffer description for the list of context classes. Since 2.10
Determines whether bracket match highlighting is activated for the source buffer.
Determines whether syntax highlighting is activated in the source buffer.
Returns the GtkSourceLanguage associated with the buffer, see gtk_source_buffer_set_language(). The returned object should not be unreferenced by the user.
Determines the number of undo levels the buffer will track for buffer edits.
Returns the list of marks of the given category at iter. If category is NULL it returns all marks at iter. Since 2.2
Returns the list of marks of the given category at line. If category is NULL, all marks at line are returned. Since 2.2
the main Gtk struct as a void*
Returns the GtkSourceStyleScheme associated with the buffer, see gtk_source_buffer_set_style_scheme(). The returned object should not be unreferenced by the user.
Returns the GtkSourceUndoManager associated with the buffer, see gtk_source_buffer_set_undo_manager(). The returned object should not be unreferenced by the user.
Moves backward to the next toggle (on or off) of the context class. If no matching context class toggles are found, returns FALSE, otherwise TRUE. Does not return toggles located at iter, only toggles after iter. Sets iter to the location of the toggle, or to the end of the buffer if no toggle is found. See the GtkSourceBuffer description for the list of context classes. Since 2.10
Moves forward to the next toggle (on or off) of the context class. If no matching context class toggles are found, returns FALSE, otherwise TRUE. Does not return toggles located at iter, only toggles after iter. Sets iter to the location of the toggle, or to the end of the buffer if no toggle is found. See the GtkSourceBuffer description for the list of context classes. Since 2.10
Check if the class context_class is set on iter. See the GtkSourceBuffer description for the list of context classes. Since 2.10
Redoes the last undo operation. Use gtk_source_buffer_can_redo() to check whether a call to this function will have any effect.
Remove all marks of category between start and end from the buffer. If category is NULL, all marks in the range will be removed. Since 2.2
Controls the bracket match highlighting function in the buffer. If activated, when you position your cursor over a bracket character (a parenthesis, a square bracket, etc.) the matching opening or closing bracket character will be highlighted.
Controls whether syntax is highlighted in the buffer. If highlight is TRUE, the text will be highlighted according to the syntax patterns specified in the language set with gtk_source_buffer_set_language(). If highlight is FALSE, syntax highlighting is disabled and all the GtkTextTag objects that have been added by the syntax highlighting engine are removed from the buffer.
Associate a GtkSourceLanguage with the buffer. If language is not-NULL and syntax highlighting is enabled (see gtk_source_buffer_set_highlight_syntax()), the syntax patterns defined in language will be used to highlight the text contained in the buffer. If language is NULL, the text contained in the buffer is not highlighted. The buffer holds a reference to language.
Sets the number of undo levels for user actions the buffer will track. If the number of user actions exceeds the limit set by this function, older actions will be discarded. If max_undo_levels is -1, no limit is set.
Sets style scheme used by the buffer. If scheme is NULL no style scheme is used.
Set the buffer undo manager. If manager is NULL the default undo manager will be set.
Undoes the last user action which modified the buffer. Use gtk_source_buffer_can_undo() to check whether a call to this function will have any effect.
the main Gtk struct
the main Gtk struct
the main Gtk struct as a void*
Inserts text into buffer at iter, applying the list of tags to the newly-inserted text. The last tag specified must be NULL to terminate the list. Equivalent to calling gtk_text_buffer_insert(), then gtk_text_buffer_apply_tag() on the inserted text; gtk_text_buffer_insert_with_tags() is just a convenience function.
Same as gtk_text_buffer_insert_with_tags(), but allows you to pass in tag names instead of tag objects.
Creates a tag and adds it to the tag table for buffer. Equivalent to adding a new tag to the buffer's tag table.
Obtain the entire text
The ::apply-tag signal is emitted to apply a tag to a range of text in a GtkTextBuffer. Applying actually occurs in the default handler. Note that if your handler runs before the default handler it must not invalidate the start and end iters (or has to revalidate them). gtk_text_buffer_apply_tag(), gtk_text_buffer_insert_with_tags(), gtk_text_buffer_insert_range().
The ::begin-user-action signal is emitted at the beginning of a single user-visible operation on a GtkTextBuffer. gtk_text_buffer_begin_user_action(), gtk_text_buffer_insert_interactive(), gtk_text_buffer_insert_range_interactive(), gtk_text_buffer_delete_interactive(), gtk_text_buffer_backspace(), gtk_text_buffer_delete_selection().
The ::changed signal is emitted when the content of a GtkTextBuffer has changed.
The ::delete-range signal is emitted to delete a range from a GtkTextBuffer. Note that if your handler runs before the default handler it must not invalidate the start and end iters (or has to revalidate them). The default signal handler revalidates the start and end iters to both point to the location where text was deleted. Handlers which run after the default handler (see g_signal_connect_after()) do not have access to the deleted text. See also: gtk_text_buffer_delete().
The ::end-user-action signal is emitted at the end of a single user-visible operation on the GtkTextBuffer. gtk_text_buffer_end_user_action(), gtk_text_buffer_insert_interactive(), gtk_text_buffer_insert_range_interactive(), gtk_text_buffer_delete_interactive(), gtk_text_buffer_backspace(), gtk_text_buffer_delete_selection(), gtk_text_buffer_backspace().
The ::insert-child-anchor signal is emitted to insert a GtkTextChildAnchor in a GtkTextBuffer. Insertion actually occurs in the default handler. Note that if your handler runs before the default handler it must not invalidate the location iter (or has to revalidate it). The default signal handler revalidates it to be placed after the inserted anchor. See also: gtk_text_buffer_insert_child_anchor().
The ::insert-pixbuf signal is emitted to insert a GdkPixbuf in a GtkTextBuffer. Insertion actually occurs in the default handler. Note that if your handler runs before the default handler it must not invalidate the location iter (or has to revalidate it). The default signal handler revalidates it to be placed after the inserted pixbuf. See also: gtk_text_buffer_insert_pixbuf().
The ::insert-text signal is emitted to insert text in a GtkTextBuffer. Insertion actually occurs in the default handler. Note that if your handler runs before the default handler it must not invalidate the location iter (or has to revalidate it). The default signal handler revalidates it to point to the end of the inserted text. gtk_text_buffer_insert(), gtk_text_buffer_insert_range().
The ::mark-deleted signal is emitted as notification after a GtkTextMark is deleted.
The ::mark-set signal is emitted as notification after a GtkTextMark is set. gtk_text_buffer_create_mark(), gtk_text_buffer_move_mark().
The ::modified-changed signal is emitted when the modified bit of a GtkTextBuffer flips.
The paste-done signal is emitted after paste operation has been completed. This is useful to properly scroll the view to the end of the pasted text. See gtk_text_buffer_paste_clipboard() for more details. Since 2.16
The ::remove-tag signal is emitted to remove all occurrences of tag from a range of text in a GtkTextBuffer. Removal actually occurs in the default handler. Note that if your handler runs before the default handler it must not invalidate the start and end iters (or has to revalidate them). gtk_text_buffer_remove_tag(). See Also GtkTextView, GtkTextIter, GtkTextMark
Obtains the number of lines in the buffer. This value is cached, so the function is very fast.
Gets the number of characters in the buffer; note that characters and bytes are not the same, you can't e.g. expect the contents of the buffer in string form to be this many bytes long. The character count is cached, so this function is very fast.
Get the GtkTextTagTable associated with this buffer.
Inserts len bytes of text at position iter. If len is -1, text must be nul-terminated and will be inserted in its entirety. Emits the "insert-text" signal; insertion actually occurs in the default handler for the signal. iter is invalidated when insertion occurs (because the buffer contents change), but the default signal handler revalidates it to point to the end of the inserted text.
Simply calls gtk_text_buffer_insert(), using the current cursor position as the insertion point.
Like gtk_text_buffer_insert(), but the insertion will not occur if iter is at a non-editable location in the buffer. Usually you want to prevent insertions at ineditable locations if the insertion results from a user action (is interactive). default_editable indicates the editability of text that doesn't have a tag affecting editability applied to it. Typically the result of gtk_text_view_get_editable() is appropriate here.
Calls gtk_text_buffer_insert_interactive() at the cursor position. default_editable indicates the editability of text that doesn't have a tag affecting editability applied to it. Typically the result of gtk_text_view_get_editable() is appropriate here.
Copies text, tags, and pixbufs between start and end (the order of start and end doesn't matter) and inserts the copy at iter. Used instead of simply getting/inserting text because it preserves images and tags. If start and end are in a different buffer from buffer, the two buffers must share the same tag table. Implemented via emissions of the insert_text and apply_tag signals, so expect those.
Same as gtk_text_buffer_insert_range(), but does nothing if the insertion point isn't editable. The default_editable parameter indicates whether the text is editable at iter if no tags enclosing iter affect editability. Typically the result of gtk_text_view_get_editable() is appropriate here.
Deletes text between start and end. The order of start and end is not actually relevant; gtk_text_buffer_delete() will reorder them. This function actually emits the "delete-range" signal, and the default handler of that signal deletes the text. Because the buffer is modified, all outstanding iterators become invalid after calling this function; however, the start and end will be re-initialized to point to the location where text was deleted.
Deletes all editable text in the given range. Calls gtk_text_buffer_delete() for each editable sub-range of [start,end). start and end are revalidated to point to the location of the last deleted range, or left untouched if no text was deleted.
Performs the appropriate action as if the user hit the delete key with the cursor at the position specified by iter. In the normal case a single character will be deleted, but when combining accents are involved, more than one character can be deleted, and when precomposed character and accent combinations are involved, less than one character will be deleted. Because the buffer is modified, all outstanding iterators become invalid after calling this function; however, the iter will be re-initialized to point to the location where text was deleted. Since 2.6
Deletes current contents of buffer, and inserts text instead. If len is -1, text must be nul-terminated. text must be valid UTF-8.
Returns the text in the range [start,end). Excludes undisplayed text (text marked with tags that set the invisibility attribute) if include_hidden_chars is FALSE. Does not include characters representing embedded images, so byte and character indexes into the returned string do not correspond to byte and character indexes into the buffer. Contrast with gtk_text_buffer_get_slice().
Returns the text in the range [start,end). Excludes undisplayed text (text marked with tags that set the invisibility attribute) if include_hidden_chars is FALSE. The returned string includes a 0xFFFC character whenever the buffer contains embedded images, so byte and character indexes into the returned string do correspond to byte and character indexes into the buffer. Contrast with gtk_text_buffer_get_text(). Note that 0xFFFC can occur in normal text as well, so it is not a reliable indicator that a pixbuf or widget is in the buffer.
Inserts an image into the text buffer at iter. The image will be counted as one character in character counts, and when obtaining the buffer contents as a string, will be represented by the Unicode "object replacement character" 0xFFFC. Note that the "slice" variants for obtaining portions of the buffer as a string include this character for pixbufs, but the "text" variants do not. e.g. see gtk_text_buffer_get_slice() and gtk_text_buffer_get_text().
Inserts a child widget anchor into the text buffer at iter. The anchor will be counted as one character in character counts, and when obtaining the buffer contents as a string, will be represented by the Unicode "object replacement character" 0xFFFC. Note that the "slice" variants for obtaining portions of the buffer as a string include this character for child anchors, but the "text" variants do not. E.g. see gtk_text_buffer_get_slice() and gtk_text_buffer_get_text(). Consider gtk_text_buffer_create_child_anchor() as a more convenient alternative to this function. The buffer will add a reference to the anchor, so you can unref it after insertion.
This is a convenience function which simply creates a child anchor with gtk_text_child_anchor_new() and inserts it into the buffer with gtk_text_buffer_insert_child_anchor(). The new anchor is owned by the buffer; no reference count is returned to the caller of gtk_text_buffer_create_child_anchor().
Creates a mark at position where. If mark_name is NULL, the mark is anonymous; otherwise, the mark can be retrieved by name using gtk_text_buffer_get_mark(). If a mark has left gravity, and text is inserted at the mark's current location, the mark will be moved to the left of the newly-inserted text. If the mark has right gravity (left_gravity = FALSE), the mark will end up on the right of newly-inserted text. The standard left-to-right cursor is a mark with right gravity (when you type, the cursor stays on the right side of the text you're typing). The caller of this function does not own a reference to the returned GtkTextMark, so you can ignore the return value if you like. Marks are owned by the buffer and go away when the buffer does. Emits the "mark-set" signal as notification of the mark's initial placement.
Moves mark to the new location where. Emits the "mark-set" signal as notification of the move.
Moves the mark named name (which must exist) to location where. See gtk_text_buffer_move_mark() for details.
Adds the mark at position where. The mark must not be added to another buffer, and if its name is not NULL then there must not be another mark in the buffer with the same name. Emits the "mark-set" signal as notification of the mark's initial placement. Since 2.12
Deletes mark, so that it's no longer located anywhere in the buffer. Removes the reference the buffer holds to the mark, so if you haven't called g_object_ref() on the mark, it will be freed. Even if the mark isn't freed, most operations on mark become invalid, until it gets added to a buffer again with gtk_text_buffer_add_mark(). Use gtk_text_mark_get_deleted() to find out if a mark has been removed from its buffer. The "mark-deleted" signal will be emitted as notification after the mark is deleted.
Deletes the mark named name; the mark must exist. See gtk_text_buffer_delete_mark() for details.
Returns the mark named name in buffer buffer, or NULL if no such mark exists in the buffer.
Returns the mark that represents the cursor (insertion point). Equivalent to calling gtk_text_buffer_get_mark() to get the mark named "insert", but very slightly more efficient, and involves less typing.
Returns the mark that represents the selection bound. Equivalent to calling gtk_text_buffer_get_mark() to get the mark named "selection_bound", but very slightly more efficient, and involves less typing. The currently-selected text in buffer is the region between the "selection_bound" and "insert" marks. If "selection_bound" and "insert" are in the same place, then there is no current selection. gtk_text_buffer_get_selection_bounds() is another convenient function for handling the selection, if you just want to know whether there's a selection and what its bounds are.
Indicates whether the buffer has some text currently selected. Since 2.10
This function moves the "insert" and "selection_bound" marks simultaneously. If you move them to the same place in two steps with gtk_text_buffer_move_mark(), you will temporarily select a region in between their old and new locations, which can be pretty inefficient since the temporarily-selected region will force stuff to be recalculated. This function moves them as a unit, which can be optimized.
This function moves the "insert" and "selection_bound" marks simultaneously. If you move them in two steps with gtk_text_buffer_move_mark(), you will temporarily select a region in between their old and new locations, which can be pretty inefficient since the temporarily-selected region will force stuff to be recalculated. This function moves them as a unit, which can be optimized. Since 2.4
Emits the "apply-tag" signal on buffer. The default handler for the signal applies tag to the given range. start and end do not have to be in order.
Emits the "remove-tag" signal. The default handler for the signal removes all occurrences of tag from the given range. start and end don't have to be in order.
Calls gtk_text_tag_table_lookup() on the buffer's tag table to get a GtkTextTag, then calls gtk_text_buffer_apply_tag().
Calls gtk_text_tag_table_lookup() on the buffer's tag table to get a GtkTextTag, then calls gtk_text_buffer_remove_tag().
Removes all tags in the range between start and end. Be careful with this function; it could remove tags added in code unrelated to the code you're currently writing. That is, using this function is probably a bad idea if you have two or more unrelated code sections that add tags.
Obtains an iterator pointing to char_offset within the given line. The char_offset must exist, offsets off the end of the line are not allowed. Note characters, not bytes; UTF-8 may encode one character as multiple bytes.
Initializes iter to a position char_offset chars from the start of the entire buffer. If char_offset is -1 or greater than the number of characters in the buffer, iter is initialized to the end iterator, the iterator one past the last valid character in the buffer.
Initializes iter to the start of the given line. If line_number is greater than the number of lines in the buffer, the end iterator is returned.
Obtains an iterator pointing to byte_index within the given line. byte_index must be the start of a UTF-8 character, and must not be beyond the end of the line. Note bytes, not characters; UTF-8 may encode one character as multiple bytes.
Initializes iter with the current position of mark.
Obtains the location of anchor within buffer.
Initialized iter with the first position in the text buffer. This is the same as using gtk_text_buffer_get_iter_at_offset() to get the iter at character offset 0.
Initializes iter with the "end iterator," one past the last valid character in the text buffer. If dereferenced with gtk_text_iter_get_char(), the end iterator has a character value of 0. The entire buffer lies in the range from the first position in the buffer (call gtk_text_buffer_get_start_iter() to get character position 0) to the end iterator.
Retrieves the first and last iterators in the buffer, i.e. the entire buffer lies within the range [start,end).
Indicates whether the buffer has been modified since the last call to gtk_text_buffer_set_modified() set the modification flag to FALSE. Used for example to enable a "save" function in a text editor.
Used to keep track of whether the buffer has been modified since the last time it was saved. Whenever the buffer is saved to disk, call gtk_text_buffer_set_modified (buffer, FALSE). When the buffer is modified, it will automatically toggled on the modified bit again. When the modified bit flips, the buffer emits the "modified-changed" signal.
Deletes the range between the "insert" and "selection_bound" marks, that is, the currently-selected text. If interactive is TRUE, the editability of the selection will be considered (users can't delete uneditable text).
Pastes the contents of a clipboard. If override_location is NULL, the pasted text will be inserted at the cursor position, or the buffer selection will be replaced if the selection is non-empty. Note: pasting is asynchronous, that is, we'll ask for the paste data and return, and at some point later after the main loop runs, the paste data will be inserted.
Copies the currently-selected text to a clipboard.
Copies the currently-selected text to a clipboard, then deletes said text if it's editable.
Returns TRUE if some text is selected; places the bounds of the selection in start and end (if the selection has length 0, then start and end are filled in with the same value). start and end will be in ascending order. If start and end are NULL, then they are not filled in, but the return value still indicates whether text is selected.
Called to indicate that the buffer operations between here and a call to gtk_text_buffer_end_user_action() are part of a single user-visible operation. The operations between gtk_text_buffer_begin_user_action() and gtk_text_buffer_end_user_action() can then be grouped when creating an undo stack. GtkTextBuffer maintains a count of calls to gtk_text_buffer_begin_user_action() that have not been closed with a call to gtk_text_buffer_end_user_action(), and emits the "begin-user-action" and "end-user-action" signals only for the outermost pair of calls. This allows you to build user actions from other user actions. The "interactive" buffer mutation functions, such as gtk_text_buffer_insert_interactive(), automatically call begin/end user action around the buffer operations they perform, so there's no need to add extra calls if you user action consists solely of a single call to one of those functions.
Should be paired with a call to gtk_text_buffer_begin_user_action(). See that function for a full explanation.
Adds clipboard to the list of clipboards in which the selection contents of buffer are available. In most cases, clipboard will be the GtkClipboard of type GDK_SELECTION_PRIMARY for a view of buffer.
Removes a GtkClipboard added with gtk_text_buffer_add_selection_clipboard().
This function deserializes rich text in format format and inserts it at iter. formats to be used must be registered using gtk_text_buffer_register_deserialize_format() or gtk_text_buffer_register_deserialize_tagset() beforehand. Since 2.10
This functions returns the value set with gtk_text_buffer_deserialize_set_can_create_tags() Since 2.10
Use this function to allow a rich text deserialization function to create new tags in the receiving buffer. Note that using this function is almost always a bad idea, because the rich text functions you register should know how to map the rich text format they handler to your text buffers set of tags. The ability of creating new (arbitrary!) tags in the receiving buffer is meant for special rich text formats like the internal one that is registered using gtk_text_buffer_register_deserialize_tagset(), because that format is essentially a dump of the internal structure of the source buffer, including its tag names. You should allow creation of tags only if you know what you are doing, e.g. if you defined a tagset name for your application suite's text buffers and you know that it's fine to receive new tags from these buffers, because you know that your application can handle the newly created tags. Since 2.10
This function returns the list of targets this text buffer can provide for copying and as DND source. The targets in the list are added with info values from the GtkTextBufferTargetInfo enum, using gtk_target_list_add_rich_text_targets() and gtk_target_list_add_text_targets(). Since 2.10
This function returns the rich text deserialize formats registered with buffer using gtk_text_buffer_register_deserialize_format() or gtk_text_buffer_register_deserialize_tagset() Since 2.10
This function returns the list of targets this text buffer supports for pasting and as DND destination. The targets in the list are added with info values from the GtkTextBufferTargetInfo enum, using gtk_target_list_add_rich_text_targets() and gtk_target_list_add_text_targets(). Since 2.10
This function returns the rich text serialize formats registered with buffer using gtk_text_buffer_register_serialize_format() or gtk_text_buffer_register_serialize_tagset() Since 2.10
This function registers a rich text deserialization function along with its mime_type with the passed buffer. Since 2.10
This function registers GTK+'s internal rich text serialization format with the passed buffer. See gtk_text_buffer_register_serialize_tagset() for details. Since 2.10
This function registers a rich text serialization function along with its mime_type with the passed buffer. Since 2.10
This function registers GTK+'s internal rich text serialization format with the passed buffer. The internal format does not comply to any standard rich text format and only works between GtkTextBuffer instances. It is capable of serializing all of a text buffer's tags and embedded pixbufs. This function is just a wrapper around gtk_text_buffer_register_serialize_format(). The mime type used for registering is "application/x-gtk-text-buffer-rich-text", or "application/x-gtk-text-buffer-rich-text;format=tagset_name" if a tagset_name was passed. The tagset_name can be used to restrict the transfer of rich text to buffers with compatible sets of tags, in order to avoid unknown tags from being pasted. It is probably the common case to pass an identifier != NULL here, since the NULL tagset requires the receiving buffer to deal with with pasting of arbitrary tags. Since 2.10
This function serializes the portion of text between start and end in the rich text format represented by format. formats to be used must be registered using gtk_text_buffer_register_serialize_format() or gtk_text_buffer_register_serialize_tagset() beforehand. Since 2.10
This function unregisters a rich text format that was previously registered using gtk_text_buffer_register_deserialize_format() or gtk_text_buffer_register_deserialize_tagset(). Since 2.10
This function unregisters a rich text format that was previously registered using gtk_text_buffer_register_serialize_format() or gtk_text_buffer_register_serialize_tagset() Since 2.10
The GtkSourceBuffer object is the model for GtkSourceView widgets. It extends the GtkTextBuffer object by adding features useful to display and edit source code such as syntax highlighting and bracket matching. It also implements support for undo/redo operations, and for the search and replace.
To create a GtkSourceBuffer use gtk_source_buffer_new() or gtk_source_buffer_new_with_language(). The second form is just a convenience function which allows you to initially set a GtkSourceLanguage.
By default highlighting is enabled, but you can disable it with gtk_source_buffer_set_highlight_syntax().
Undo and Redo
A custom GtkSourceUndoManager can be implemented and set with gtk_source_buffer_set_undo_manager(). However the default implementation should be suitable for most uses. By default, actions that can be undone or redone are defined as groups of operations between a call to gtk_text_buffer_begin_user_action() and gtk_text_buffer_end_user_action(). In general, this happens whenever the user presses any key which modifies the buffer. But the default undo manager will try to merge similar consecutive actions, such as multiple character insertions on the same line, into one action. But, inserting a newline starts a new action.
The default undo manager remembers the "modified" state of the buffer, and restore it when an action is undone or redone. It can be useful in a text editor to know whether the file is saved. See gtk_text_buffer_get_modified() and gtk_text_buffer_set_modified().
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Context Classes
It is possible to retrieve some information from the syntax highlighting engine. There are currently three context classes, that are applied to regions of a GtkSourceBuffer:
comment: the region delimits a comment;
string: the region delimits a string;
no-spell-check: the region should not be spell checked.