点击ImageSwitcher显示的图片即可切换到为美女换衣全屏界面，手指在界面上滑动，滑动处的衣服就被褪掉了，很黄很暴力，大家要hold住呀！！
其实啊这个实现就是两张图片，一张底图，一张上面的图，上面的图都被抹掉了，下面的图就出来了，主要是PorterDuff和PorterDuffXfermode的利用，APIDEMO里面也有相关的介绍。
具体下载目录在 /pub/Android源码集锦/2011年/12月/Android小应用帮美女更衣系列一(附源码)/
好，贴出主要代码:
package com.picture; import android.app.Activity; import android.content.Context; import android.content.Intent; import android.graphics.Bitmap; import android.graphics.Bitmap.Config; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Path; import android.graphics.PorterDuff; import android.graphics.PorterDuffXfermode; import android.media.MediaPlayer; import android.os.Bundle; import android.util.DisplayMetrics; import android.view.MotionEvent; import android.view.View; import android.view.WindowManager; public class RemoveClothActivity extends Activity { private int SCREEN_W; private int SCREEN_H; private int imagePosition; private MediaPlayer mp3Player; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);//设置全屏 Intent intent = getIntent(); imagePosition = intent.getIntExtra("imagePosition", 0); initMP3Player(); setContentView(new MyView(this)); } private void initMP3Player(){ mp3Player = MediaPlayer.create(RemoveClothActivity.this, R.raw.higirl); mp3Player.setLooping(false); } private void playMusic(){ mp3Player.start(); } class MyView extends View { private Bitmap mBitmap; private Canvas mCanvas; private Paint mPaint; private Path mPath; private float mX, mY; private static final float TOUCH_TOLERANCE = 4; public MyView(Context context) { super(context); setFocusable(true); setScreenWH(); setBackGround(); // 1.if icon1 is a image,you can open MENU_ITEM_COMMENT bellow // Bitmap bm = createBitmapFromSRC(); // if you want to set icon1 image's alpha,you can open // MENU_ITEM_COMMENT bellow // bm = setBitmapAlpha(bm, 100); // if you want to scale icon1 image,you can open MENU_ITEM_COMMENT // bellow // bm = scaleBitmapFillScreen(bm); // 2.if icon1 is color // Bitmap bm = createBitmapFromARGB(0x8800ff00, SCREEN_W, SCREEN_H); int drawableId = 0; try { drawableId = R.drawable.class.getDeclaredField( "pre" + imagePosition).getInt(this); } catch (IllegalArgumentException e) { e.printStackTrace(); } catch (SecurityException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (NoSuchFieldException e) { e.printStackTrace(); } Bitmap bm = scaleBitmapFillScreen(BitmapFactory.decodeResource(getResources(), drawableId)); seticon1Bitmap(bm); } private void setScreenWH() { // get screen info DisplayMetrics dm = new DisplayMetrics(); dm = this.getResources().getDisplayMetrics(); // get screen width int screenWidth = dm.widthPixels; // get screen height int screenHeight = dm.heightPixels; SCREEN_W = screenWidth; SCREEN_H = screenHeight; } private Bitmap createBitmapFromSRC() { return BitmapFactory.decodeResource(getResources(), R.drawable.icon1); } /** * * @param colorARGB * should like 0x8800ff00 * @param width * @param height * @return */ private Bitmap createBitmapFromARGB(int colorARGB, int width, int height) { int[] argb = new int[width * height]; for (int i = 0; i < argb.length; i++) { argb[i] = colorARGB; } return Bitmap.createBitmap(argb, width, height, Config.ARGB_8888); } /** * * @param bm * @param alpha * ,and alpha should be like ox00000000-oxff000000 * @note set bitmap's alpha * @return */ /* * private Bitmap setBitmapAlpha(Bitmap bm, int alpha) { int[] argb = * new int[bm.getWidth() * bm.getHeight()]; bm.getPixels(argb, 0, * bm.getWidth(), 0, 0, bm.getWidth(), bm .getHeight()); * * * for (int i = 0; i < argb.length; i++) { * * argb[i] = ((alpha) | (argb[i] & 0x00FFFFFF)); } return * Bitmap.createBitmap(argb, bm.getWidth(), bm.getHeight(), * Config.ARGB_8888); } */ /** * * @param bm * @param alpha * ,alpha should be between 0 and 255 * @note set bitmap's alpha * @return */ private Bitmap setBitmapAlpha(Bitmap bm, int alpha) { int[] argb = new int[bm.getWidth() * bm.getHeight()]; bm.getPixels(argb, 0, bm.getWidth(), 0, 0, bm.getWidth(), bm.getHeight()); for (int i = 0; i < argb.length; i++) { argb[i] = ((alpha << 24) | (argb[i] & 0x00FFFFFF)); } return Bitmap.createBitmap(argb, bm.getWidth(), bm.getHeight(), Config.ARGB_8888); } /** * * @param bm * @note if bitmap is smaller than screen, you can scale it fill the * screen. * @return */ private Bitmap scaleBitmapFillScreen(Bitmap bm) { return Bitmap.createScaledBitmap(bm, SCREEN_W, SCREEN_H, true); } private void setBackGround(){ int drawableId = 0; try { drawableId = R.drawable.class.getDeclaredField( "after" + imagePosition).getInt(this); } catch (IllegalArgumentException e) { e.printStackTrace(); } catch (SecurityException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (NoSuchFieldException e) { e.printStackTrace(); } setBackgroundResource(drawableId); } /** * * @param bm * @note set icon1 bitmap , which overlay on background. */ private void seticon1Bitmap(Bitmap bm) { // setting paint mPaint = new Paint(); mPaint.setAlpha(0); mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN)); mPaint.setAntiAlias(true); mPaint.setDither(true); mPaint.setStyle(Paint.Style.STROKE); mPaint.setStrokeJoin(Paint.Join.ROUND); mPaint.setStrokeCap(Paint.Cap.ROUND); mPaint.setStrokeWidth(20); // set path mPath = new Path(); ; // converting bitmap into mutable bitmap mBitmap = Bitmap.createBitmap(SCREEN_W, SCREEN_H, Config.ARGB_8888); mCanvas = new Canvas(); mCanvas.setBitmap(mBitmap); // drawXY will result on that Bitmap // be sure parameter is bm, not mBitmap mCanvas.drawBitmap(bm, 0, 0, null); } @Override protected void onDraw(Canvas canvas) { canvas.drawBitmap(mBitmap, 0, 0, null); mCanvas.drawPath(mPath, mPaint); super.onDraw(canvas); } private void touch_start(float x, float y) { mPath.reset(); mPath.moveTo(x, y); mX = x; mY = y; } private void touch_move(float x, float y) { float dx = Math.abs(x - mX); float dy = Math.abs(y - mY); if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) { mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2); mX = x; mY = y; } } private void touch_up() { mPath.lineTo(mX, mY); // commit the path to our offscreen mCanvas.drawPath(mPath, mPaint); // kill this so we don't double draw mPath.reset(); } @Override public boolean onTouchEvent(MotionEvent event) { float x = event.getX(); float y = event.getY(); switch (event.getAction()) { case MotionEvent.ACTION_DOWN: touch_start(x, y); invalidate(); break; case MotionEvent.ACTION_MOVE: touch_move(x, y); invalidate(); break; case MotionEvent.ACTION_UP: touch_up(); invalidate(); playMusic(); break; } return true; } } }