安卓開發(fā)中Bitmap源碼實例

　　package android.graphics;

　　import java.awt.image.BufferedImage;

　　import java.io.File;

　　import java.io.IOException;

　　import java.io.InputStream;

　　import javax.imageio.ImageIO;

　　public final class Bitmap extends _Original_Bitmap {

　　private BufferedImage mImage;

　　public Bitmap(File input) throws IOException {

　　super(1, true, null, -1);

　　mImage = ImageIO.read(input);

　　}

　　public Bitmap(InputStream is) throws IOException {

　　s

　　mImage = ImageIO.read(is);

　　}

　　Bitmap(BufferedImage image) {

　　super(1, true, null, -1);

　　mImage = image;

　　}

　　public BufferedImage getImage() {

　　return mImage;

　　}

　　// ----- overriden methods

　　public enum Config {

　　// these native values must match up with the enum in SkBitmap.h

　　ALPHA_8 (2),

　　RGB_565 (4),

　　ARGB_4444 (5),

　　ARGB_8888 (6);

　　Config(int ni) {

　　this.nativeInt = ni;

　　}

　　final int nativeInt;

　　/* package */ static Config nativeToConfig(int ni) {

　　return sConfigs[ni];

　　}

　　private static Config sConfigs[] = {

　　null, null, ALPHA_8, null, RGB_565, ARGB_4444, ARGB_8888

　　};

　　}

　　@Override

　　public int getWidth() {

　　return mImage.getWidth();

　　}

　　@Override

　　public int getHeight() {

　　return mImage.getHeight();

　　}

　　/**

　　* Returns an immutable bitmap from the source bitmap. The new bitmap may

　　* be the same object as source, or a copy may have been made.

　　*/

　　public static Bitmap createBitmap(Bitmap src) {

　　return createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), null, false);

　　}

　　/**

　　* Returns an immutable bitmap from the specified subset of the source

　　* bitmap. The new bitmap may be the same object as source, or a copy may

　　* have been made.

　　*

　　* @param source The bitmap we are subsetting

　　* @param x The x coordinate of the first pixel in source

　　* @param y The y coordinate of the first pixel in source

　　* @param width The number of pixels in each row

　　* @param height The number of rows

　　*/

　　public static Bitmap createBitmap(Bitmap source, int x, int y,

　　int width, int height) {

　　return new Bitmap(source.mImage.getSubimage(x, y, width, height));

　　}

　　/**

　　* Returns an immutable bitmap from subset of the source bitmap,

　　* transformed by the optional matrix.

　　*

　　* @param source The bitmap we are subsetting