Graphics.UI.Gtk.Multiline.TextMark

A position in the buffer preserved across buffer modifications

Detail

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 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.

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.

Class Hierarchy

| GObject
| +----TextMark

Types

data TextMark

Instances

Eq TextMark

Ord TextMark

GObjectClass TextMark

TextMarkClass TextMark

class GObjectClass o => TextMarkClass o

Instances

TextMarkClass TextMark

castToTextMark :: GObjectClass obj => obj -> TextMark

gTypeTextMark :: GType

toTextMark :: TextMarkClass o => o -> TextMark

type MarkName = DefaultGlibString

The name of a mark.

Constructors

textMarkNew

Arguments

:: Maybe MarkName

markName - name for mark, or Nothing

-> Bool

leftGravity - whether the mark has left gravity

-> IO 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 this 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).

• Available since Gtk+ version 2.12

Methods

textMarkSetVisible :: TextMarkClass self => self -> Bool -> IO ()

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.

textMarkGetVisible :: TextMarkClass self => self -> IO Bool

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

textMarkGetDeleted :: TextMarkClass self => self -> IO Bool

Returns True if the mark has been removed from its buffer with textBufferDeleteMark. Marks can't be used once deleted.

textMarkGetName :: TextMarkClass self => self -> IO (Maybe MarkName)

Returns the mark name; returns Nothing for anonymous marks.

textMarkGetBuffer :: TextMarkClass self => self -> IO (Maybe TextBuffer)

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

textMarkGetLeftGravity :: TextMarkClass self => self -> IO Bool

Determines whether the mark has left gravity.

The name is misleading as Arabic, Hebrew and some other languages have the beginning of a line towards the right.

Attributes

textMarkName :: TextMarkClass self => ReadAttr self (Maybe MarkName)

Retreives the name of a mark.

textMarkVisible :: TextMarkClass self => Attr self Bool

The 'visible' property. See textMarkGetVisible and textMarkSetVisible

textMarkLeftGravity :: TextMarkClass self => ReadAttr self Bool

Determines whether the mark keeps to the left when text is inserted at its position.