Android APIs
public class

Shader

extends Object
java.lang.Object
   ↳ android.graphics.Shader
Known Direct Subclasses

Class Overview

Shader is the based class for objects that return horizontal spans of colors during drawing. A subclass of Shader is installed in a Paint calling paint.setShader(shader). After that any object (other than a bitmap) that is drawn with that paint will get its color(s) from the shader.

Summary

Nested Classes
enum Shader.TileMode  
Public Constructors
Shader()
Public Methods
boolean getLocalMatrix(Matrix localM)
Return true if the shader has a non-identity local matrix.
void setLocalMatrix(Matrix localM)
Set the shader's local matrix.
Protected Methods
void finalize()
Invoked when the garbage collector has detected that this instance is no longer reachable.
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Inherited Methods
From class java.lang.Object

Public Constructors

public Shader ()

Added in API level 1

Public Methods

public boolean getLocalMatrix (Matrix localM)

Added in API level 1

Return true if the shader has a non-identity local matrix.

Parameters
localM If not null, it is set to the shader's local matrix.
Returns
boolean true if the shader has a non-identity local matrix

public void setLocalMatrix (Matrix localM)

Added in API level 1

Set the shader's local matrix. Passing null will reset the shader's matrix to identity.

Parameters
localM The shader's new local matrix, or null to specify identity

Protected Methods

protected void finalize ()

Added in API level 1

Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.

Throws
Throwable