Summary: Ctors | Methods | Protected Methods | Inherited Methods | [Expand All]

public class

Picture

extends Object

java.lang.Object
↳	android.graphics.Picture

Class Overview

A picture records drawing calls (via the canvas returned by beginRecording) and can then play them back (via picture.draw(canvas) or canvas.drawPicture). The picture's contents can also be written to a stream, and then later restored to a new picture (via writeToStream / createFromStream). For most content (esp. text, lines, rectangles), drawing a sequence from a picture can be faster than the equivalent API calls, since the picture performs its playback without incurring any java-call overhead.

Summary

Public Constructors
	Picture()
	Picture(Picture src) Create a picture by making a copy of what has already been recorded in src.

Public Methods
Canvas	beginRecording(int width, int height) To record a picture, call beginRecording() and then draw into the Canvas that is returned.
static Picture	createFromStream(InputStream stream) Create a new picture (already recorded) from the data in the stream.
void	draw(Canvas canvas) Draw this picture on the canvas.
void	endRecording() Call endRecording when the picture is built.
int	getHeight() Get the height of the picture as passed to beginRecording.
int	getWidth() Get the width of the picture as passed to beginRecording.
void	writeToStream(OutputStream stream) Write the picture contents to a stream.

Protected Methods
void	finalize() Is called before the object's memory is being reclaimed by the VM.

[Expand]

Inherited Methods

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Is called before the object's memory is being reclaimed by the VM.
final Class<? extends Object>	getClass() Returns the unique instance of Class which represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.

Public Constructors

public Picture ()

public Picture (Picture src)

Create a picture by making a copy of what has already been recorded in src. The contents of src are unchanged, and if src changes later, those changes will not be reflected in this picture.

Public Methods

public Canvas beginRecording (int width, int height)

To record a picture, call beginRecording() and then draw into the Canvas that is returned. Nothing we appear on screen, but all of the draw commands (e.g. drawRect(...)) will be recorded. To stop recording, call endRecording(). At this point the Canvas that was returned must no longer be referenced, and nothing should be drawn into it.

public static Picture createFromStream (InputStream stream)

Create a new picture (already recorded) from the data in the stream. This data was generated by a previous call to writeToStream().

public void draw (Canvas canvas)

Draw this picture on the canvas. The picture may have the side effect of changing the matrix and clip of the canvas.

Parameters

canvas	The picture is drawn to this canvas

public void endRecording ()

Call endRecording when the picture is built. After this call, the picture may be drawn, but the canvas that was returned by beginRecording must not be referenced anymore. This is automatically called if Picture.draw() or Canvas.drawPicture() is called.

public int getHeight ()

Get the height of the picture as passed to beginRecording. This does not reflect (per se) the content of the picture.

public int getWidth ()

Get the width of the picture as passed to beginRecording. This does not reflect (per se) the content of the picture.

public void writeToStream (OutputStream stream)

Write the picture contents to a stream. The data can be used to recreate the picture in this or another process by calling createFromStream.

Protected Methods

protected void finalize ()

Is called before the object's memory is being reclaimed by the VM. This can only happen once the VM has detected, during a run of the garbage collector, that the object is no longer reachable by any thread of the running application.

The method can be used to free system resources or perform other cleanup before the object is garbage collected. The default implementation of the method is empty, which is also expected by the VM, but subclasses can override finalize() as required. Uncaught exceptions which are thrown during the execution of this method cause it to terminate immediately but are otherwise ignored.

Note that the VM does guarantee that finalize() is called at most once for any object, but it doesn't guarantee when (if at all) finalize() will be called. For example, object B's finalize() can delay the execution of object A's finalize() method and therefore it can delay the reclamation of A's memory. To be safe, use a ReferenceQueue, because it provides more control over the way the VM deals with references during garbage collection.

Throws

Throwable

Classes

Enums