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AlphaAnimation

public class AlphaAnimation
extends Animation

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


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

Summary

Inherited XML attributes

Inherited constants

Public constructors

AlphaAnimation(Context context, AttributeSet attrs)

Constructor used when an AlphaAnimation is loaded from a resource.

AlphaAnimation(float fromAlpha, float toAlpha)

Constructor to use when building an AlphaAnimation from code

Public methods

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.

Protected methods

void applyTransformation(float interpolatedTime, Transformation t)

Changes the alpha property of the supplied Transformation

Inherited methods

Public constructors

AlphaAnimation

added in API level 1
public AlphaAnimation (Context context, 
                AttributeSet attrs)

Constructor used when an AlphaAnimation is loaded from a resource.

Parameters
context Context: Application context to use

attrs AttributeSet: Attribute set from which to read values

AlphaAnimation

added in API level 1
public AlphaAnimation (float fromAlpha, 
                float toAlpha)

Constructor to use when building an AlphaAnimation from code

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

toAlpha float: Ending alpha value for the animation.

Public methods

willChangeBounds

added in API level 1
public boolean willChangeBounds ()

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.

Returns
boolean true if this animation will change the view's bounds

willChangeTransformationMatrix

added in API level 1
public boolean willChangeTransformationMatrix ()

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.

Returns
boolean true if this animation will change the transformation matrix

Protected methods

applyTransformation

added in API level 1
protected void applyTransformation (float interpolatedTime, 
                Transformation t)

Changes the alpha property of the supplied Transformation

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

t Transformation: The Transformation object to fill in with the current transforms.