仿微信朋友圈雙擊頂部回到最前端(GestureDetector.OnDoubleTapListener)

 listView.setSelection(0);

1. public class MainActivity extends Activity implements OnTouchListener{  

2.   

3.     private GestureDetector mGestureDetector;     

4.       

5.   

6.     @Override  

7.     protected void onCreate(Bundle savedInstanceState) {  

8.         super.onCreate(savedInstanceState);  

9.         setContentView(R.layout.activity_main);  

10.           

11.   

12.       mGestureDetector = new GestureDetector(new gestureListener()); //使用派生自OnGestureListener  

13.       mGestureDetector.setOnDoubleTapListener(new doubleTapListener());  

14.           

15.       TextView tv = (TextView)findViewById(R.id.tv);  

16.       tv.setOnTouchListener(this);  

17.       tv.setFocusable(true);     

18.       tv.setClickable(true);     

19.       tv.setLongClickable(true);   

20.     }  

21.       

22.       

23.     /*  

24.      * 在onTouch()方法中，我們調用GestureDetector的onTouchEvent()方法，將捕捉到的MotionEvent交給GestureDetector  

25.      * 來分析是否有合適的callback函數來處理用戶的手勢  

26.      */    

27.     public boolean onTouch(View v, MotionEvent event) {  

28.         return mGestureDetector.onTouchEvent(event);     

29.     }  

30.       

31.     //OnGestureListener監聽  

32.     private class gestureListener implements GestureDetector.OnGestureListener{  

33.   

34.         public boolean onDown(MotionEvent e) {  

35.             Log.i("MyGesture", "onDown");     

36.             Toast.makeText(MainActivity.this, "onDown", Toast.LENGTH_SHORT).show();     

37.             return false;  

38.         }  

39.   

40.         public void onShowPress(MotionEvent e) {  

41.             Log.i("MyGesture", "onShowPress");     

42.             Toast.makeText(MainActivity.this, "onShowPress", Toast.LENGTH_SHORT).show();     

43.         }  

44.   

45.         public boolean onSingleTapUp(MotionEvent e) {  

46.             Log.i("MyGesture", "onSingleTapUp");     

47.             Toast.makeText(MainActivity.this, "onSingleTapUp", Toast.LENGTH_SHORT).show();     

48.             return true;     

49.         }  

50.   

51.         public boolean onScroll(MotionEvent e1, MotionEvent e2,  

52.                 float distanceX, float distanceY) {  

53.             Log.i("MyGesture22", "onScroll:"+(e2.getX()-e1.getX()) +"   "+distanceX);     

54.             Toast.makeText(MainActivity.this, "onScroll", Toast.LENGTH_LONG).show();     

55.               

56.             return true;     

57.         }  

58.   

59.         public void onLongPress(MotionEvent e) {  

60.              Log.i("MyGesture", "onLongPress");     

61.              Toast.makeText(MainActivity.this, "onLongPress", Toast.LENGTH_LONG).show();     

62.         }  

63.   

64.         public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,  

65.                 float velocityY) {  

66.             Log.i("MyGesture", "onFling");     

67.             Toast.makeText(MainActivity.this, "onFling", Toast.LENGTH_LONG).show();     

68.             return true;  

69.         }  

70.     };  

71.       

72.     //OnDoubleTapListener監聽  

73.     private class doubleTapListener implements GestureDetector.OnDoubleTapListener{  

74.   

75.         public boolean onSingleTapConfirmed(MotionEvent e) {  

76.             Log.i("MyGesture", "onSingleTapConfirmed");     

77.             Toast.makeText(MainActivity.this, "onSingleTapConfirmed", Toast.LENGTH_LONG).show();    

78.             return true;  

79.         }  

80.   

81.         public boolean onDoubleTap(MotionEvent e) {  

82.             Log.i("MyGesture", "onDoubleTap");     

83.             Toast.makeText(MainActivity.this, "onDoubleTap", Toast.LENGTH_LONG).show();    

84.             return true;  

85.         }  

86.   

87.         public boolean onDoubleTapEvent(MotionEvent e) {  

88.             Log.i("MyGesture", "onDoubleTapEvent");     

89.             Toast.makeText(MainActivity.this, "onDoubleTapEvent", Toast.LENGTH_LONG).show();    

90.             return true;  

91.         }  

92.     };  

93. }  

參考： 

用戶手勢檢測-GestureDetector使用詳解