Class: GdkPixbuf::PixbufAnimation

Inherits:
Object
  • Object
show all
Defined in:
(unknown)

Overview

Modules supporting animations must derive a type from
Gdk::PixbufAnimation, providing suitable implementations of the
virtual functions.

Direct Known Subclasses

PixbufNonAnim, PixbufSimpleAnim

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(async_result) ⇒ GdkPixbuf::PixbufAnimation

Finishes an asynchronous pixbuf animation creation operation started with
[funcGdkPixbuf.PixbufAnimation.new_from_stream_async].

Parameters:

  • async_result (Gio::AsyncResult) —

    a GAsync::Result

Class Method Details

.new_from_stream_async(stream, cancellable, callback, user_data) ⇒ nil

Creates a new animation by asynchronously loading an image from an input stream.

For more details see gdk_pixbuf_new_from_stream(), which is the synchronous
version of this function.

When the operation is finished, callback will be called in the main thread.
You can then call gdk_pixbuf_animation_new_from_stream_finish() to get the
result of the operation.

Parameters:

  • stream (Gio::InputStream) —

    a GInput::Stream from which to load the animation

  • cancellable (Gio::Cancellable) —

    optional #GCancellable object

  • callback (Gio::AsyncReadyCallback) —

    a GAsyncReadyCallback to call when the pixbuf is loaded

  • user_data (GObject) —

    the data to pass to the callback function

Returns:

  • (nil)

Instance Method Details

#get_iter(start_time) ⇒ GdkPixbuf::PixbufAnimationIter

Get an iterator for displaying an animation.

The iterator provides the frames that should be displayed at a
given time.

start_time would normally come from g_get_current_time(), and marks
the beginning of animation playback. After creating an iterator, you
should immediately display the pixbuf returned by
gdk_pixbuf_animation_iter_get_pixbuf(). Then, you should install
a timeout (with g_timeout_add()) or by some other mechanism ensure
that you'll update the image after
gdk_pixbuf_animation_iter_get_delay_time() milliseconds. Each time
the image is updated, you should reinstall the timeout with the new,
possibly-changed delay time.

As a shortcut, if start_time is NULL, the result of
g_get_current_time() will be used automatically.

To update the image (i.e. possibly change the result of
gdk_pixbuf_animation_iter_get_pixbuf() to a new frame of the animation),
call gdk_pixbuf_animation_iter_advance().

If you're using Gdk::PixbufLoader, in addition to updating the image
after the delay time, you should also update it whenever you
receive the area_updated signal and
gdk_pixbuf_animation_iter_on_currently_loading_frame() returns
TRUE. In this case, the frame currently being fed into the loader
has received new data, so needs to be refreshed. The delay time for
a frame may also be modified after an area_updated signal, for
example if the delay time for a frame is encoded in the data after
the frame itself. So your timeout should be reinstalled after any
area_updated signal.

A delay time of -1 is possible, indicating "infinite".

Parameters:

  • start_time (GLib::TimeVal) —

    time when the animation starts playing

Returns:

#height ⇒ Integer

Queries the height of the bounding box of a pixbuf animation.

Returns:

  • (Integer) —

    Height of the bounding box of the animation.

#is_static_image ⇒ Boolean

Checks whether the animation is a static image.

If you load a file with gdk_pixbuf_animation_new_from_file() and it
turns out to be a plain, unanimated image, then this function will
return TRUE. Use gdk_pixbuf_animation_get_static_image() to retrieve
the image.

Returns:

  • (Boolean) —

    TRUE if the "animation" was really just an image

#ref ⇒ GdkPixbuf::PixbufAnimation

Adds a reference to an animation.

Returns:

#static_image ⇒ GdkPixbuf::Pixbuf

Retrieves a static image for the animation.

If an animation is really just a plain image (has only one frame),
this function returns that image.

If the animation is an animation, this function returns a reasonable
image to use as a static unanimated image, which might be the first
frame, or something more sophisticated depending on the file format.

If an animation hasn't loaded any frames yet, this function will
return NULL.

Returns:

#unref ⇒ nil

Removes a reference from an animation.

Returns:

  • (nil)

#width ⇒ Integer

Queries the width of the bounding box of a pixbuf animation.

Returns:

  • (Integer) —

    Width of the bounding box of the animation.