GI.Gtk.Objects.TextMark

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

A TextMark is like a bookmark in a text buffer; it preserves a position in the text. You can convert the mark to an iterator using textBufferGetIterAtMark. 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.

Note that “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 textBufferDeleteMark. Once deleted from the buffer, a mark is essentially useless.

Marks optionally have names; these can be convenient to avoid passing the TextMark object around.

Marks are typically created using the textBufferCreateMark function.

Exported types

newtype TextMark

Constructors

TextMark (ManagedPtr TextMark)

Instances

GObject TextMark

Methods

gobjectType :: TextMark -> IO GType

IsObject TextMark

IsTextMark TextMark

class GObject o => IsTextMark o

Instances

(GObject a, UnknownAncestorError Constraint TextMark a) => IsTextMark a

IsTextMark TextMark

toTextMark :: (MonadIO m, IsTextMark o) => o -> m TextMark

noTextMark :: Maybe TextMark

Methods

getBuffer

textMarkGetBuffer

Arguments

:: (HasCallStack, MonadIO m, IsTextMark a)

=> a

mark: a TextMark

-> m TextBuffer

Returns: the mark’s TextBuffer

Gets the buffer this mark is located inside, or Nothing if the mark is deleted.

getDeleted

textMarkGetDeleted

Arguments

:: (HasCallStack, MonadIO m, IsTextMark a)

=> a

mark: a TextMark

-> m Bool

Returns: whether the mark is deleted

Returns True if the mark has been removed from its buffer with textBufferDeleteMark. See textBufferAddMark for a way to add it to a buffer again.

getLeftGravity

textMarkGetLeftGravity

Arguments

:: (HasCallStack, MonadIO m, IsTextMark a)

=> a

mark: a TextMark

-> m Bool

Returns: True if the mark has left gravity, False otherwise

Determines whether the mark has left gravity.

getName

textMarkGetName

Arguments

:: (HasCallStack, MonadIO m, IsTextMark a)

=> a

mark: a TextMark

-> m (Maybe Text)

Returns: mark name

Returns the mark name; returns NULL for anonymous marks.

getVisible

textMarkGetVisible

Arguments

:: (HasCallStack, MonadIO m, IsTextMark a)

=> a

mark: a TextMark

-> m Bool

Returns: True if visible

Returns True if the mark is visible (i.e. a cursor is displayed for it).

new

textMarkNew

Arguments

:: (HasCallStack, MonadIO m)

=> Maybe Text

name: mark name or Nothing

-> Bool

leftGravity: whether the mark should have left gravity

-> m TextMark

Returns: new TextMark

Creates a text mark. Add it to a buffer using textBufferAddMark. If name is Nothing, the mark is anonymous; otherwise, the mark can be retrieved by name using textBufferGetMark. 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 (leftGravity = 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).

Since: 2.12

setVisible

textMarkSetVisible

Arguments

:: (HasCallStack, MonadIO m, IsTextMark a)

=> a

mark: a TextMark

-> Bool

setting: visibility of mark

-> m ()

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.

Properties

leftGravity

constructTextMarkLeftGravity :: IsTextMark o => Bool -> IO (GValueConstruct o)

getTextMarkLeftGravity :: (MonadIO m, IsTextMark o) => o -> m Bool

name

constructTextMarkName :: IsTextMark o => Text -> IO (GValueConstruct o)

getTextMarkName :: (MonadIO m, IsTextMark o) => o -> m (Maybe Text)