A position in the buffer preserved across buffer modifications
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.
A <gtk-text-mark> is like a bookmark in a text buffer; it preserves a
position in the text. You can convert the mark to an iterator using
gtk-text-buffer-get-iter-at-mark. Unlike iterators, marks remain valid
across buffer mutations, because their behavior is defined when text is inserted
or deleted. When text containing a mark is deleted, the mark remains in the
position originally occupied by the deleted text. When text is inserted at a
mark, a mark with left gravity will be moved to the beginning of the
newly-inserted text, and a mark with right gravity will be moved to the
end.
"left" and "right" here refer to logical direction (left is the toward the start of the buffer); in some languages such as Hebrew the logically-leftmost text is not actually on the left when displayed.
Marks are reference counted, but the reference count only controls the validity
of the memory; marks can be deleted from the buffer at any time with
gtk-text-buffer-delete-mark. Once deleted from the buffer, a mark is
essentially useless.
Marks optionally have names; these can be convenient to avoid passing the
<gtk-text-mark> object around.
Marks are typically created using the gtk-text-buffer-create-mark
function.
Derives from
<gobject>.This class defines the following slots:
name- Mark name
left-gravity- Whether the mark has left gravity
<gtk-text-mark>) (setting bool)Sets the visibility of mark; the insertion point is normally visible, i.e. you can see it as a vertical bar. Also, the text widget uses a visible mark to indicate where a drop will occur when dragging-and-dropping text. Most other marks are not visible. Marks are not visible by default.
- mark
- a
<gtk-text-mark>- setting
- visibility of mark
<gtk-text-mark>) ⇒ (ret bool)Returns ‘
#t’ if the mark is visible (i.e. a cursor is displayed for it)
- mark
- a
<gtk-text-mark>- ret
- ‘
#t’ if visible
<gtk-text-mark>) ⇒ (ret bool)Returns ‘
#t’ if the mark has been removed from its buffer withgtk-text-buffer-delete-mark. Marks can't be used once deleted.
- mark
- a
<gtk-text-mark>- ret
- whether the mark is deleted
<gtk-text-mark>) ⇒ (ret mchars)Returns the mark name; returns NULL for anonymous marks.
- mark
- a
<gtk-text-mark>- ret
- mark name