class Gtk::TextBuffer

Overview

Stores text and attributes for display in a GtkTextView.

You may wish to begin by reading the text widget conceptual overview, which gives an overview of all the objects and data types related to the text widget and how they work together.

GtkTextBuffer can support undoing changes to the buffer content, see Gtk::TextBuffer#enable_undo=.

Defined in:

lib/gi-crystal/src/auto/gtk-4.0/text_buffer.cr

Constructors

Class Method Summary

Instance Method Summary

Instance methods inherited from class GObject::Object

bind_property(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags) : GObject::Binding bind_property, bind_property_full(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags, transform_to : GObject::Closure, transform_from : GObject::Closure) : GObject::Binding bind_property_full, data(key : String) : Pointer(Void)? data, finalize finalize, freeze_notify : Nil freeze_notify, getv(names : Enumerable(String), values : Enumerable(_)) : Nil getv, notify(property_name : String) : Nil notify, notify_by_pspec(pspec : GObject::ParamSpec) : Nil notify_by_pspec, notify_signal notify_signal, property(property_name : String, value : _) : Nil property, qdata(quark : UInt32) : Pointer(Void)? qdata, ref_count : UInt32 ref_count, run_dispose : Nil run_dispose, set_data(key : String, data : Pointer(Void)?) : Nil set_data, set_property(property_name : String, value : _) : Nil set_property, steal_data(key : String) : Pointer(Void)? steal_data, steal_qdata(quark : UInt32) : Pointer(Void)? steal_qdata, thaw_notify : Nil thaw_notify, to_unsafe : Pointer(Void) to_unsafe, watch_closure(closure : GObject::Closure) : Nil watch_closure

Constructor methods inherited from class GObject::Object

cast(obj : GObject::Object) : self cast, cast?(obj : GObject::Object) : self? cast?, new(pointer : Pointer(Void), transfer : GICrystal::Transfer)
new
new
, newv(object_type : UInt64, parameters : Enumerable(GObject::Parameter)) : self newv

Class methods inherited from class GObject::Object

compat_control(what : UInt64, data : Pointer(Void)?) : UInt64 compat_control, g_type : UInt64 g_type, interface_find_property(g_iface : GObject::TypeInterface, property_name : String) : GObject::ParamSpec interface_find_property, interface_list_properties(g_iface : GObject::TypeInterface) : Enumerable(GObject::ParamSpec) interface_list_properties

Constructor Detail

def self.new(table : Gtk::TextTagTable?) : self #

Creates a new text buffer.


def self.new #

Initialize a new TextBuffer.


def self.new(*, can_redo : Bool? = nil, can_undo : Bool? = nil, cursor_position : Int32? = nil, enable_undo : Bool? = nil, has_selection : Bool? = nil, tag_table : Gtk::TextTagTable? = nil, text : String? = nil) #

Class Method Detail

def self.g_type : UInt64 #

Returns the type id (GType) registered in GLib type system.


Instance Method Detail

def add_mark(mark : Gtk::TextMark, where : Gtk::TextIter) : Nil #

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 [signal@Gtk.TextBuffer::mark-set] signal as notification of the mark's initial placement.


def add_selection_clipboard(clipboard : Gdk::Clipboard) : Nil #

Adds @clipboard to the list of clipboards in which the selection contents of @buffer are available.

In most cases, @clipboard will be the GdkClipboard returned by Gtk::Widget#primary_clipboard for a view of @buffer.


def apply_tag(tag : Gtk::TextTag, start : Gtk::TextIter, end _end : Gtk::TextIter) : Nil #

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.


def apply_tag_by_name(name : String, start : Gtk::TextIter, end _end : Gtk::TextIter) : Nil #

Emits the “apply-tag” signal on @buffer.

Calls Gtk::TextTagTable#lookup on the buffer’s tag table to get a GtkTextTag, then calls Gtk::TextBuffer#apply_tag.


def apply_tag_signal #

def backspace(iter : Gtk::TextIter, interactive : Bool, default_editable : Bool) : Bool #

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.


def begin_irreversible_action : Nil #

Denotes the beginning of an action that may not be undone.

This will cause any previous operations in the undo/redo queue to be cleared.

This should be paired with a call to Gtk::TextBuffer#end_irreversible_action after the irreversible action has completed.

You may nest calls to gtk_text_buffer_begin_irreversible_action() and gtk_text_buffer_end_irreversible_action() pairs.


def begin_user_action : Nil #

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::TextBuffer#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.


def begin_user_action_signal #

def bounds : Gtk::TextIter #

Retrieves the first and last iterators in the buffer, i.e. the entire buffer lies within the range [@start,@end).


def can_redo : Bool #

Gets whether there is a redoable action in the history.


def can_redo? : Bool #

def can_undo : Bool #

Gets whether there is an undoable action in the history.


def can_undo? : Bool #

def changed_signal #

def char_count : Int32 #

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.


def copy_clipboard(clipboard : Gdk::Clipboard) : Nil #

Copies the currently-selected text to a clipboard.


def create_child_anchor(iter : Gtk::TextIter) : Gtk::TextChildAnchor #

Creates and inserts a child anchor.

This is a convenience function which simply creates a child anchor with Gtk::TextChildAnchor.new and inserts it into the buffer with Gtk::TextBuffer#insert_child_anchor.

The new anchor is owned by the buffer; no reference count is returned to the caller of this function.


def create_mark(mark_name : String?, where : Gtk::TextIter, left_gravity : Bool) : Gtk::TextMark #

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::TextBuffer#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 [signal@Gtk.TextBuffer::mark-set] signal as notification of the mark's initial placement.


def cursor_position : Int32 #

def cut_clipboard(clipboard : Gdk::Clipboard, default_editable : Bool) : Nil #

Copies the currently-selected text to a clipboard, then deletes said text if it’s editable.


def delete(start : Gtk::TextIter, end _end : Gtk::TextIter) : Nil #

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.


def delete_interactive(start_iter : Gtk::TextIter, end_iter : Gtk::TextIter, default_editable : Bool) : Bool #

Deletes all editable text in the given range.

Calls Gtk::TextBuffer#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.


def delete_mark(mark : Gtk::TextMark) : Nil #

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::TextBuffer#add_mark. Use Gtk::TextMark#deleted to find out if a mark has been removed from its buffer.

The [signal@Gtk.TextBuffer::mark-deleted] signal will be emitted as notification after the mark is deleted.


def delete_mark_by_name(name : String) : Nil #

Deletes the mark named @name; the mark must exist.

See Gtk::TextBuffer#delete_mark for details.


def delete_range_signal #

def delete_selection(interactive : Bool, default_editable : Bool) : Bool #

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).


def enable_undo : Bool #

Gets whether the buffer is saving modifications to the buffer to allow for undo and redo actions.

See Gtk::TextBuffer#begin_irreversible_action and Gtk::TextBuffer#end_irreversible_action to create changes to the buffer that cannot be undone.


def enable_undo=(enable_undo : Bool) : Nil #

Sets whether or not to enable undoable actions in the text buffer.

Undoable actions in this context are changes to the text content of the buffer. Changes to tags and marks are not tracked.

If enabled, the user will be able to undo the last number of actions up to Gtk::TextBuffer#max_undo_levels.

See Gtk::TextBuffer#begin_irreversible_action and Gtk::TextBuffer#end_irreversible_action to create changes to the buffer that cannot be undone.


def enable_undo? : Bool #

def end_irreversible_action : Nil #

Denotes the end of an action that may not be undone.

This will cause any previous operations in the undo/redo queue to be cleared.

This should be called after completing modifications to the text buffer after Gtk::TextBuffer#begin_irreversible_action was called.

You may nest calls to gtk_text_buffer_begin_irreversible_action() and gtk_text_buffer_end_irreversible_action() pairs.


def end_iter : Gtk::TextIter #

Initializes @iter with the “end iterator,” one past the last valid character in the text buffer.

If dereferenced with Gtk::TextIter#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::TextBuffer#start_iter to get character position 0) to the end iterator.


def end_user_action : Nil #

Ends a user-visible operation.

Should be paired with a call to Gtk::TextBuffer#begin_user_action. See that function for a full explanation.


def end_user_action_signal #

def has_selection : Bool #

Indicates whether the buffer has some text currently selected.


def has_selection? : Bool #

def insert(iter : Gtk::TextIter, text : String, len : Int32) : Nil #

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.


def insert : Gtk::TextMark #

Returns the mark that represents the cursor (insertion point).

Equivalent to calling Gtk::TextBuffer#mark to get the mark named “insert”, but very slightly more efficient, and involves less typing.


def insert_at_cursor(text : String, len : Int32) : Nil #

Inserts @text in @buffer.

Simply calls Gtk::TextBuffer#insert, using the current cursor position as the insertion point.


def insert_child_anchor(iter : Gtk::TextIter, anchor : Gtk::TextChildAnchor) : Nil #

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::TextBuffer#slice and Gtk::TextBuffer#text.

Consider Gtk::TextBuffer#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.


def insert_child_anchor_signal #

def insert_interactive(iter : Gtk::TextIter, text : String, len : Int32, default_editable : Bool) : Bool #

Inserts @text in @buffer.

Like Gtk::TextBuffer#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::TextView#editable is appropriate here.


def insert_interactive_at_cursor(text : String, len : Int32, default_editable : Bool) : Bool #

Inserts @text in @buffer.

Calls Gtk::TextBuffer#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::TextView#editable is appropriate here.


def insert_markup(iter : Gtk::TextIter, markup : String, len : Int32) : Nil #

Inserts the text in @markup at position @iter.

@markup will be inserted in its entirety and must be nul-terminated and valid UTF-8. Emits the [signal@Gtk.TextBuffer::insert-text] signal, possibly multiple times; insertion actually occurs in the default handler for the signal. @iter will point to the end of the inserted text on return.


def insert_paintable(iter : Gtk::TextIter, paintable : Gdk::Paintable) : Nil #

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 paintable, but the “text” variants do not. e.g. see Gtk::TextBuffer#slice and Gtk::TextBuffer#text.


def insert_paintable_signal #

def insert_range(iter : Gtk::TextIter, start : Gtk::TextIter, end _end : Gtk::TextIter) : Nil #

Copies text, tags, and paintables between @start and @end and inserts the copy at @iter.

The order of @start and @end doesn’t matter.

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.


def insert_range_interactive(iter : Gtk::TextIter, start : Gtk::TextIter, end _end : Gtk::TextIter, default_editable : Bool) : Bool #

Copies text, tags, and paintables between @start and @end and inserts the copy at @iter.

Same as Gtk::TextBuffer#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::TextView#editable is appropriate here.


def insert_text_signal #

def iter_at_child_anchor(anchor : Gtk::TextChildAnchor) : Gtk::TextIter #

Obtains the location of @anchor within @buffer.


def iter_at_line(line_number : Int32) : Gtk::TextIter #

Initializes @iter to the start of the given line.

If @line_number is greater than or equal to the number of lines in the @buffer, the end iterator is returned.


def iter_at_line_index(line_number : Int32, byte_index : Int32) : Gtk::TextIter #

Obtains an iterator pointing to @byte_index within the given line.

@byte_index must be the start of a UTF-8 character. Note bytes, not characters; UTF-8 may encode one character as multiple bytes.

If @line_number is greater than or equal to the number of lines in the @buffer, the end iterator is returned. And if @byte_index is off the end of the line, the iterator at the end of the line is returned.


def iter_at_line_offset(line_number : Int32, char_offset : Int32) : Gtk::TextIter #

Obtains an iterator pointing to @char_offset within the given line.

Note characters, not bytes; UTF-8 may encode one character as multiple bytes.

If @line_number is greater than or equal to the number of lines in the @buffer, the end iterator is returned. And if @char_offset is off the end of the line, the iterator at the end of the line is returned.


def iter_at_mark(mark : Gtk::TextMark) : Gtk::TextIter #

Initializes @iter with the current position of @mark.


def iter_at_offset(char_offset : Int32) : Gtk::TextIter #

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.


def line_count : Int32 #

Obtains the number of lines in the buffer.

This value is cached, so the function is very fast.


def mark(name : String) : Gtk::TextMark? #

Returns the mark named @name in buffer @buffer, or %NULL if no such mark exists in the buffer.


def mark_deleted_signal #

def mark_set_signal #

def max_undo_levels : UInt32 #

Gets the maximum number of undo levels to perform.

If 0, unlimited undo actions may be performed. Note that this may have a memory usage impact as it requires storing an additional copy of the inserted or removed text within the text buffer.


def max_undo_levels=(max_undo_levels : UInt32) : Nil #

Sets the maximum number of undo levels to perform.

If 0, unlimited undo actions may be performed. Note that this may have a memory usage impact as it requires storing an additional copy of the inserted or removed text within the text buffer.


def modified : Bool #

Indicates whether the buffer has been modified since the last call to Gtk::TextBuffer#modified= set the modification flag to %FALSE.

Used for example to enable a “save” function in a text editor.


def modified=(setting : Bool) : Nil #

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 [signal@Gtk.TextBuffer::modified-changed] signal.


def modified_changed_signal #

def move_mark(mark : Gtk::TextMark, where : Gtk::TextIter) : Nil #

Moves @mark to the new location @where.

Emits the [signal@Gtk.TextBuffer::mark-set] signal as notification of the move.


def move_mark_by_name(name : String, where : Gtk::TextIter) : Nil #

Moves the mark named @name (which must exist) to location @where.

See Gtk::TextBuffer#move_mark for details.


def paste_clipboard(clipboard : Gdk::Clipboard, override_location : Gtk::TextIter?, default_editable : Bool) : Nil #

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.


def paste_done_signal #

def place_cursor(where : Gtk::TextIter) : Nil #

This function moves the “insert” and “selection_bound” marks simultaneously.

If you move them to the same place in two steps with Gtk::TextBuffer#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.


def redo : Nil #

Redoes the next redoable action on the buffer, if there is one.


def redo_signal #

def remove_all_tags(start : Gtk::TextIter, end _end : Gtk::TextIter) : Nil #

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.


def remove_selection_clipboard(clipboard : Gdk::Clipboard) : Nil #

Removes a GdkClipboard added with gtk_text_buffer_add_selection_clipboard().


def remove_tag(tag : Gtk::TextTag, start : Gtk::TextIter, end _end : Gtk::TextIter) : Nil #

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.


def remove_tag_by_name(name : String, start : Gtk::TextIter, end _end : Gtk::TextIter) : Nil #

Emits the “remove-tag” signal.

Calls Gtk::TextTagTable#lookup on the buffer’s tag table to get a GtkTextTag, then calls Gtk::TextBuffer#remove_tag.


def remove_tag_signal #

def select_range(ins : Gtk::TextIter, bound : Gtk::TextIter) : Nil #

This function moves the “insert” and “selection_bound” marks simultaneously.

If you move them in two steps with Gtk::TextBuffer#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.


def selection_bound : Gtk::TextMark #

Returns the mark that represents the selection bound.

Equivalent to calling Gtk::TextBuffer#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::TextBuffer#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.


def selection_bounds : Gtk::TextIter #

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.


def selection_content : Gdk::ContentProvider #

Get a content provider for this buffer.

It can be used to make the content of @buffer available in a GdkClipboard, see Gdk::Clipboard#content=.


def set_text(text : String, len : Int32) : Nil #

Deletes current contents of @buffer, and inserts @text instead.

If @len is -1, @text must be nul-terminated. @text must be valid UTF-8.


def slice(start : Gtk::TextIter, end _end : Gtk::TextIter, include_hidden_chars : Bool) : String #

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::TextBuffer#text. Note that 0xFFFC can occur in normal text as well, so it is not a reliable indicator that a paintable or widget is in the buffer.


def start_iter : Gtk::TextIter #

Initialized @iter with the first position in the text buffer.

This is the same as using Gtk::TextBuffer#iter_at_offset to get the iter at character offset 0.


def tag_table : Gtk::TextTagTable #

Get the GtkTextTagTable associated with this buffer.


def tag_table=(value : Gtk::TextTagTable?) : Gtk::TextTagTable? #

def text(start : Gtk::TextIter, end _end : Gtk::TextIter, include_hidden_chars : Bool) : String #

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::TextBuffer#slice.


def text : String #

def text=(value : String) : String #

def undo : Nil #

Undoes the last undoable action on the buffer, if there is one.


def undo_signal #