public
class
AnimationDrawable
extends DrawableContainer
implements
Runnable,
Animatable
java.lang.Object | |||
↳ | android.graphics.drawable.Drawable | ||
↳ | android.graphics.drawable.DrawableContainer | ||
↳ | android.graphics.drawable.AnimationDrawable |
An object used to create frame-by-frame animations, defined by a series of Drawable objects, which can be used as a View object's background.
The simplest way to create a frame-by-frame animation is to define the
animation in an XML file, placed in the res/drawable/ folder, and set it as
the background to a View object. Then, call start()
to run the
animation.
An AnimationDrawable defined in XML consists of a single
<animation-list>
element and a series of nested
<item>
tags. Each item defines a frame of the animation. See
the example below.
spin_animation.xml file in res/drawable/ folder:
<!-- Animation frames are wheel0.png through wheel5.png files inside the res/drawable/ folder --> <animation-list android:id="@+id/selected" android:oneshot="false"> <item android:drawable="@drawable/wheel0" android:duration="50" /> <item android:drawable="@drawable/wheel1" android:duration="50" /> <item android:drawable="@drawable/wheel2" android:duration="50" /> <item android:drawable="@drawable/wheel3" android:duration="50" /> <item android:drawable="@drawable/wheel4" android:duration="50" /> <item android:drawable="@drawable/wheel5" android:duration="50" /> </animation-list>
Here is the code to load and play this animation.
// Load the ImageView that will host the animation and // set its background to our AnimationDrawable XML resource. ImageView img = (ImageView)findViewById(R.id.spinning_wheel_image); img.setBackgroundResource(R.drawable.spin_animation); // Get the background, which has been compiled to an AnimationDrawable object. AnimationDrawable frameAnimation = (AnimationDrawable) img.getBackground(); // Start the animation (looped playback by default). frameAnimation.start();
For more information about animating with AnimationDrawable
, read the
Drawable Animation
developer guide.
XML attributes | |
---|---|
android:drawable |
Reference to a drawable resource to use for the frame. |
android:duration |
Amount of time (in milliseconds) to display this frame. |
android:oneshot |
If true, the animation will only run a single time and then stop. |
android:variablePadding |
If true, allows the drawable's padding to change based on the current state that is selected. |
android:visible |
Provides initial visibility state of the drawable; the default value is false. |
Public constructors | |
---|---|
AnimationDrawable()
|
Public methods | |
---|---|
void
|
addFrame(Drawable frame, int duration)
Adds a frame to the animation |
int
|
getDuration(int i)
|
Drawable
|
getFrame(int index)
|
int
|
getNumberOfFrames()
|
void
|
inflate(Resources r, XmlPullParser parser, AttributeSet attrs, Resources.Theme theme)
Inflate this Drawable from an XML resource optionally styled by a theme. |
boolean
|
isOneShot()
|
boolean
|
isRunning()
Indicates whether the animation is currently running or not. |
Drawable
|
mutate()
Make this drawable mutable. |
void
|
run()
This method exists for implementation purpose only and should not be called directly. |
void
|
setOneShot(boolean oneShot)
Sets whether the animation should play once or repeat. |
boolean
|
setVisible(boolean visible, boolean restart)
Sets whether this AnimationDrawable is visible. |
void
|
start()
Starts the animation from the first frame, looping if necessary. |
void
|
stop()
Stops the animation at the current frame. |
void
|
unscheduleSelf(Runnable what)
Use the current |
Protected methods | |
---|---|
void
|
setConstantState(DrawableContainer.DrawableContainerState state)
|
Inherited methods | |
---|---|
From
class
android.graphics.drawable.DrawableContainer
| |
From
class
android.graphics.drawable.Drawable
| |
From
class
java.lang.Object
| |
From
interface
android.graphics.drawable.Drawable.Callback
| |
From
interface
java.lang.Runnable
| |
From
interface
android.graphics.drawable.Animatable
|
Reference to a drawable resource to use for the frame. If not given, the drawable must be defined by the first child tag.
Must be a reference to another resource, in the form "@[+][package:]type:name
"
or to a theme attribute in the form "?[package:][type:]name
".
This corresponds to the global attribute
resource symbol drawable
.
Amount of time (in milliseconds) to display this frame.
Must be an integer value, such as "100
".
This may also be a reference to a resource (in the form
"@[package:]type:name
") or
theme attribute (in the form
"?[package:][type:]name
")
containing a value of this type.
This corresponds to the global attribute
resource symbol duration
.
If true, the animation will only run a single time and then stop. If false (the default), it will continually run, restarting at the first frame after the last has finished.
Must be a boolean value, either "true
" or "false
".
This may also be a reference to a resource (in the form
"@[package:]type:name
") or
theme attribute (in the form
"?[package:][type:]name
")
containing a value of this type.
This corresponds to the global attribute
resource symbol oneshot
.
If true, allows the drawable's padding to change based on the current state that is selected. If false, the padding will stay the same (based on the maximum padding of all the states). Enabling this feature requires that the owner of the drawable deal with performing layout when the state changes, which is often not supported.
Must be a boolean value, either "true
" or "false
".
This may also be a reference to a resource (in the form
"@[package:]type:name
") or
theme attribute (in the form
"?[package:][type:]name
")
containing a value of this type.
This corresponds to the global attribute
resource symbol variablePadding
.
Provides initial visibility state of the drawable; the default
value is false. See
setVisible(boolean, boolean)
.
Must be a boolean value, either "true
" or "false
".
This may also be a reference to a resource (in the form
"@[package:]type:name
") or
theme attribute (in the form
"?[package:][type:]name
")
containing a value of this type.
This corresponds to the global attribute
resource symbol visible
.
void addFrame (Drawable frame, int duration)
Adds a frame to the animation
Parameters | |
---|---|
frame |
Drawable :
The frame to add |
duration |
int :
How long in milliseconds the frame should appear
|
int getDuration (int i)
Parameters | |
---|---|
i |
int
|
Returns | |
---|---|
int |
The duration in milliseconds of the frame at the specified index |
Drawable getFrame (int index)
Parameters | |
---|---|
index |
int
|
Returns | |
---|---|
Drawable |
The Drawable at the specified frame index |
int getNumberOfFrames ()
Returns | |
---|---|
int |
The number of frames in the animation |
void inflate (Resources r, XmlPullParser parser, AttributeSet attrs, Resources.Theme theme)
Inflate this Drawable from an XML resource optionally styled by a theme. This can't be called more than once for each Drawable. Note that framework may have called this once to create the Drawable instance from XML resource.
Parameters | |
---|---|
r |
Resources :
Resources used to resolve attribute values |
parser |
XmlPullParser :
XML parser from which to inflate this Drawable |
attrs |
AttributeSet :
Base set of attribute values |
theme |
Resources.Theme :
Theme to apply, may be null |
Throws | |
---|---|
XmlPullParserException |
|
IOException |
boolean isOneShot ()
Returns | |
---|---|
boolean |
True of the animation will play once, false otherwise |
boolean isRunning ()
Indicates whether the animation is currently running or not.
Returns | |
---|---|
boolean |
true if the animation is running, false otherwise |
Drawable mutate ()
Make this drawable mutable. This operation cannot be reversed. A mutable drawable is guaranteed to not share its state with any other drawable. This is especially useful when you need to modify properties of drawables loaded from resources. By default, all drawables instances loaded from the same resource share a common state; if you modify the state of one instance, all the other instances will receive the same modification. Calling this method on a mutable Drawable will have no effect.
Returns | |
---|---|
Drawable |
This drawable. |
void run ()
This method exists for implementation purpose only and should not be
called directly. Invoke start()
instead.
See also:
void setOneShot (boolean oneShot)
Sets whether the animation should play once or repeat.
Parameters | |
---|---|
oneShot |
boolean :
Pass true if the animation should only play once
|
boolean setVisible (boolean visible, boolean restart)
Sets whether this AnimationDrawable is visible.
When the drawable becomes invisible, it will pause its animation. A subsequent change to
visible with restart
set to true will restart the animation from the
first frame. If restart
is false, the drawable will resume from the most recent
frame. If the drawable has already reached the last frame, it will then loop back to the
first frame, unless it's a one shot drawable (set through setOneShot(boolean)
),
in which case, it will stay on the last frame.
Parameters | |
---|---|
visible |
boolean :
true if visible, false otherwise |
restart |
boolean :
when visible, true to force the animation to restart
from the first frame |
Returns | |
---|---|
boolean |
true if the new visibility is different than its previous state |
void start ()
Starts the animation from the first frame, looping if necessary. This method has no effect if the animation is running.
Note: Do not call this in the
onCreate(Bundle)
method of your activity, because
the AnimationDrawable
is not yet fully attached to the window.
If you want to play the animation immediately without requiring
interaction, then you might want to call it from the
onWindowFocusChanged(boolean)
method in your
activity, which will get called when Android brings your window into
focus.
See also:
void stop ()
Stops the animation at the current frame. This method has no effect if the animation is not running.
See also:
void unscheduleSelf (Runnable what)
Use the current Drawable.Callback
implementation to have this Drawable
unscheduled. Does nothing if there is no Callback attached to the
Drawable.
Parameters | |
---|---|
what |
Runnable :
The runnable that you no longer want called. |
void setConstantState (DrawableContainer.DrawableContainerState state)
Parameters | |
---|---|
state |
DrawableContainer.DrawableContainerState
|