1. View view = activity.getWindow().getDecorView();
2. true);
3.
4. = view.getDrawingCache();
然后我们需呀计算出我们选定区域的坐标点，注意正选和反选的计算方式不同 ，
1. public boolean onTouch(View v, MotionEvent event) {
2. if(event.getAction() == MotionEvent.ACTION_DOWN){
3. x = 0;
4. y = 0;
5. width = 0;
6. height = 0;
7. x = (int) event.getX();
8. y = (int) event.getY();
9. }
10. if(event.getAction() == MotionEvent.ACTION_MOVE){
11. m = (int) event.getX();
12. n = (int) event.getY();
13. myView.setSeat(x, y, m, n);
14. myView.postInvalidate();
15. }
16. if(event.getAction() == MotionEvent.ACTION_UP){
17. if(event.getX()>x){
18. width = (int)event.getX()-x;
19. }else{
20. width = (int)(x-event.getX());
21. x = (int) event.getX();
22. }
23. if(event.getY()>y){
24. height = (int) event.getY()-y;
25. }else{
26. height = (int)(y-event.getY());
27. y = (int) event.getY();
28. }
29. image2.setImageBitmap(getBitmap(this));
30. }
31. if(myView.isSign()){
32. return false;
33. }else{
34. return true;
35. }
36.
然后为我们计算出来的坐标区域添加选中效果
1. protected void onDraw(Canvas canvas) {
2. if(sign){
3. paint.setColor(Color.TRANSPARENT);
4. }else{
5. paint.setColor(Color.RED);
6. paint.setAlpha(80);
7. canvas.drawRect(new Rect(x, y, m, n), paint);
8. }
9. super.onDraw(canvas);
10.
最后生成我们需要的图片展示出来，顺便保存到SD卡下一张。
1. frame = new Rect();
2. activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
3. int toHeight = frame.top;
4. bitmap = Bitmap.createBitmap(bitmap, x, y+2*toHeight, width, height);
5. try {
6. FileOutputStream fout = new FileOutputStream("mnt/sdcard/test.png");
7. bitmap.compress(Bitmap.CompressFormat.PNG, 100, fout);
8. } catch (FileNotFoundException e) {
9. // TODO Auto-generated catch block
10. e.printStackTrace();
11. }
12. view.setDrawingCacheEnabled(false);
