Copyright	Will Thompson Iñaki García Etxebarria and Jonas Platte
License	LGPL-2.1
Maintainer	Iñaki García Etxebarria (inaki@blueleaf.cc)
Safe Haskell	None
Language	Haskell2010

GI.Gtk.Objects.OffscreenWindow

Contents

Exported types
Methods

Description

GtkOffscreenWindow is strictly intended to be used for obtaining snapshots of widgets that are not part of a normal widget hierarchy. Since OffscreenWindow is a toplevel widget you cannot obtain snapshots of a full window with it since you cannot pack a toplevel widget in another toplevel.

The idea is to take a widget and manually set the state of it, add it to a GtkOffscreenWindow and then retrieve the snapshot as a Surface or Pixbuf.

GtkOffscreenWindow derives from Window only as an implementation detail. Applications should not use any API specific to Window to operate on this object. It should be treated as a Bin that has no parent widget.

When contained offscreen widgets are redrawn, GtkOffscreenWindow will emit a Widget::damage-event signal.

Synopsis

newtype OffscreenWindow = OffscreenWindow (ManagedPtr OffscreenWindow)
class (GObject o, IsDescendantOf OffscreenWindow o) => IsOffscreenWindow o
toOffscreenWindow :: (MonadIO m, IsOffscreenWindow o) => o -> m OffscreenWindow
noOffscreenWindow :: Maybe OffscreenWindow
offscreenWindowGetPixbuf :: (HasCallStack, MonadIO m, IsOffscreenWindow a) => a -> m (Maybe Pixbuf)
offscreenWindowGetSurface :: (HasCallStack, MonadIO m, IsOffscreenWindow a) => a -> m (Maybe Surface)
offscreenWindowNew :: (HasCallStack, MonadIO m) => m OffscreenWindow

Exported types

newtype OffscreenWindow Source #

Memory-managed wrapper type.

Constructors

OffscreenWindow (ManagedPtr OffscreenWindow)

Instances

GObject OffscreenWindow Source #
Instance details Defined in GI.Gtk.Objects.OffscreenWindow Methods gobjectType :: IO GType #
HasParentTypes OffscreenWindow Source #
Instance details Defined in GI.Gtk.Objects.OffscreenWindow
type ParentTypes OffscreenWindow Source #
Instance details Defined in GI.Gtk.Objects.OffscreenWindow type ParentTypes OffscreenWindow = Window ': (Bin ': (Container ': (Widget ': (Object ': (ImplementorIface ': (Buildable ': ([] :: [Type])))))))

class (GObject o, IsDescendantOf OffscreenWindow o) => IsOffscreenWindow o Source #

Type class for types which can be safely cast to OffscreenWindow, for instance with toOffscreenWindow.

Instances

(GObject o, IsDescendantOf OffscreenWindow o) => IsOffscreenWindow o Source #
Instance details Defined in GI.Gtk.Objects.OffscreenWindow

toOffscreenWindow :: (MonadIO m, IsOffscreenWindow o) => o -> m OffscreenWindow Source #

Cast to OffscreenWindow, for types for which this is known to be safe. For general casts, use castTo.

noOffscreenWindow :: Maybe OffscreenWindow Source #

A convenience alias for Nothing :: Maybe OffscreenWindow.

Methods

getPixbuf

offscreenWindowGetPixbuf Source #

Arguments

:: (HasCallStack, MonadIO m, IsOffscreenWindow a)
=> a	`offscreen`: the `OffscreenWindow` contained widget.
-> m (Maybe Pixbuf)	Returns: A `Pixbuf` pointer, or `Nothing`.

Retrieves a snapshot of the contained widget in the form of a Pixbuf. This is a new pixbuf with a reference count of 1, and the application should unreference it once it is no longer needed.

Since: 2.20

getSurface

offscreenWindowGetSurface Source #

Arguments

:: (HasCallStack, MonadIO m, IsOffscreenWindow a)
=> a	`offscreen`: the `OffscreenWindow` contained widget.
-> m (Maybe Surface)	Returns: A `Surface` pointer to the offscreen surface, or `Nothing`.

Retrieves a snapshot of the contained widget in the form of a Surface. If you need to keep this around over window resizes then you should add a reference to it.

Since: 2.20

new

offscreenWindowNew Source #

Arguments

:: (HasCallStack, MonadIO m)
=> m OffscreenWindow	Returns: A pointer to a `Widget`

Creates a toplevel container widget that is used to retrieve snapshots of widgets without showing them on the screen.

Since: 2.20