Android實現圖片按任意路徑截取

使用 Android提供的Path實現圖片的截取，重寫View的onTouchEvent方法和onDraw方法,onTouchEvent負責實現截取路徑的構件,onDraw進行刷新頁面,重寫View類的代碼如下 :

1. public class MyView extends View {
2. private Drawable mDrawable;
3. private Path mPath;
4. private float mX = -1;
5. private float mY = -1;
6. private float mPastX;
7. private float mPastY;
9. public MyView(Context context) {
10. super(context);
11. // TODO Auto-generated constructor stub
12. mPath = new Path();
13. }
15. public void setDrawable(Drawable pDrawable){
16. mDrawable = pDrawable;
17. }
19. @Override
20. protected void onDraw(Canvas canvas) {
21. // TODO Auto-generated method stub
22. super.onDraw(canvas);
23. Log.i("xiao", "onDraw");
24. mDrawable.setBounds(0, 0, getWidth(), getHeight());
25. Rect lRect = mDrawable.getBounds();
26. Log.i("xiao", "lRect.left = " + lRect.left + " top = " + lRect.top + " right = " + lRect.right + " bottom = " + lRect.bottom);
27. if(!mPath.isEmpty()){
28. Log.i("xiao", "!mPath.isEmpty()");
29. canvas.clipPath(mPath);
30. //mDrawable.draw(canvas);
31. }
33. mDrawable.draw(canvas);
34. }
36. @Override
37. public boolean onTouchEvent(MotionEvent event) {
38. // TODO Auto-generated method stub
39. Log.i("xiao", "onTouchEvent");
40. int lAction = event.getAction();
41. if(mX != -1){
42. mPastX = mX;
43. mPastY = mY;
44. }
45. mX = event.getX();
46. mY = event.getY();
47. switch(lAction){
48. case MotionEvent.ACTION_DOWN:
49. mPath.reset();
50. mPath.moveTo(mX, mY);
51. break;
52. case MotionEvent.ACTION_MOVE:
53. mPath.quadTo(mPastX, mPastY, (mX + mPastX) / 2, (mY + mPastY) / 2);
54. break;
55. case MotionEvent.ACTION_UP:
56. mPath.lineTo(mX, mY);
57. mX = -1;
58. mY = -1;
59. invalidate();
60. break;
61. default:
63. break;
64. }
65. return true;
66. }
67. }

Activity主要負責獲取和設置Drawable和設置布局,代碼如下:

1. private MyView mView;
3. @Override
4. public void onCreate(Bundle savedInstanceState) {
5. super.onCreate(savedInstanceState);
7. mView = new MyView(this);
8. mView.setDrawable(this.getResources().getDrawable(R.drawable.test1));
9. this.setContentView(mView);
10. }

未截取時效果:

畫一個路徑截取效果圖:

Android實現圖片按任意路徑截取源碼下載地址：

免費下載地址在 http://linux.linuxidc.com/

用戶名與密碼都是www.linuxidc.com

具體下載目錄在 /2012年資料/9月/13日/Android實現圖片按任意路徑截取