android.view.animation
Class AlphaAnimation

java.lang.Object
  android.view.animation.Animation
      android.view.animation.AlphaAnimation

public class AlphaAnimation
extends Animation

An animation that controls the alpha level of an object. Useful for fading things in and out. This animation ends up changing the alpha property of a Transformation

Nested Class Summary

Nested classes/interfaces inherited from class android.view.animation.Animation

Animation.AnimationListener, Animation.Description

Field Summary

Fields inherited from class android.view.animation.Animation

ABSOLUTE, INFINITE, mCycleFlip, mDuration, mEnded, mFillAfter, mFillBefore, mInitialized, mInterpolator, mListener, mRepeatCount, mRepeated, mRepeatMode, mStarted, mStartOffset, mStartTime, RELATIVE_TO_PARENT, RELATIVE_TO_SELF, RESTART, REVERSE, START_ON_FIRST_FRAME, ZORDER_BOTTOM, ZORDER_NORMAL, ZORDER_TOP

Constructor Summary

AlphaAnimation(Context context, AttributeSet attrs)
Constructor used whan an AlphaAnimation is loaded from a resource.

AlphaAnimation(float fromAlpha, float toAlpha)
Constructor to use when building an AlphaAnimation from code

Method Summary

protected void	applyTransformation(float interpolatedTime, Transformation t) Changes the alpha property of the supplied Transformation
boolean	willChangeBounds() Indicates whether or not this animation will affect the bounds of the animated view.
boolean	willChangeTransformationMatrix() Indicates whether or not this animation will affect the transformation matrix.

Methods inherited from class android.view.animation.Animation

ensureInterpolator, getDuration, getFillAfter, getFillBefore, getInterpolator, getRepeatCount, getRepeatMode, getStartOffset, getStartTime, getTransformation, getZAdjustment, hasEnded, hasStarted, initialize, isInitialized, reset, resolveSize, restrictDuration, scaleCurrentDuration, setAnimationListener, setDuration, setFillAfter, setFillBefore, setInterpolator, setInterpolator, setRepeatCount, setRepeatMode, setStartOffset, setStartTime, setZAdjustment, start, startNow

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AlphaAnimation

public AlphaAnimation(Context context,
                      AttributeSet attrs)

Constructor used whan an AlphaAnimation is loaded from a resource.

Parameters:

context - Application context to use

attrs - Attribute set from which to read values

AlphaAnimation

public AlphaAnimation(float fromAlpha,
                      float toAlpha)

Constructor to use when building an AlphaAnimation from code

Parameters:

fromAlpha - Starting alpha value for the animation, where 1.0 means fully opaque and 0.0 means fully transparent.

toAlpha - Ending alpha value for the animation.

Method Detail

applyTransformation

protected void applyTransformation(float interpolatedTime,
                                   Transformation t)

Changes the alpha property of the supplied Transformation

Overrides:

applyTransformation in class Animation

Parameters:

interpolatedTime - The value of the normalized time (0.0 to 1.0) after it has been run through the interpolation function.

t - The Transofrmation object to fill in with the current transforms.

willChangeTransformationMatrix

public boolean willChangeTransformationMatrix()

Description copied from class: Animation

Indicates whether or not this animation will affect the transformation matrix. For instance, a fade animation will not affect the matrix whereas a scale animation will.

Overrides:

willChangeTransformationMatrix in class Animation

Returns:

true if this animation will change the transformation matrix

willChangeBounds

public boolean willChangeBounds()

Description copied from class: Animation

Indicates whether or not this animation will affect the bounds of the animated view. For instance, a fade animation will not affect the bounds whereas a 200% scale animation will.

Overrides:

willChangeBounds in class Animation

Returns:

true if this animation will change the view's bounds