Android gesturedetector Gesture Recognition class

To enhance the mouse response to events, Android provides the gesturedetector Gesture Recognition class. Gesturedetector. ongesturelistener is used to obtain the currently triggered operation gestures (single tap up, show press, long press, scroll, down, and fling), including the following:

Boolean ondoubletap (motionevent E)
Explanation: triggered when the second touch is down under double-click
Boolean ondoubletapevent (motionevent E)
Explanation: Double-click triggers both touch down and up, which can be distinguished by E. getaction.
Boolean ondown (motionevent E)
Explanation: triggered when touch is down
Boolean onfling (motionevent E1, motionevent E2, float velocityx, float velocityy)

Explanation: Touch is triggered when it is up after sliding a little distance.
Void onlongpress (motionevent E)
Explanation: triggered when touch is down without moving
Boolean onscroll (motionevent E1, motionevent E2, float distancex, float distancey)

Explanation: It is triggered when sliding is reached.
Void onshowpress (motionevent E)
Explanation: triggered when touch is not sliding
(Compared with ondown and onlongpress
Ondown must be triggered immediately as long as touch down.
After touchdown, onshowpress is triggered before onlongpress after a while without sliding.
Therefore, it does not slide after touchdown. ondown-> onshowpress-> onlongpress is triggered in this order.

Boolean onsingletapconfirmed (motionevent E)
Boolean onsingletapup (motionevent E)
Explanation: the above two functions are triggered when the touch is down without moving (onscroll) or long-pressed (onlongpress.

Click very fast (do not slide) touchup:
Ondown-> onsingletapup-> onsingletapconfirmed
Click a slightly slower (do not slide) touchup:
Ondown-> onshowpress-> onsingletapup-> onsingletapconfirmed

To use gesturedetector, You need to override the ontouchevent event in the view. For example:

[Java]
View plaincopyprint?

1. Gesturedetector mgesture = NULL;
   
2. @ Override
3. Public Boolean ontouch (view V, motionevent event)
   
4. {
5. // Todo auto-generated method stub
   
6. Return mgesture. ontouchevent (event );
   
7. }

Gesturedetector mgesture = NULL; <br/> @ override <br/> Public Boolean ontouch (view V, motionevent event) <br/>{< br/> // todo auto-generated method stub <br/> return mgesture. ontouchevent (event); <br/>}

A detailed test example is as follows:

[CPP]
View plaincopyprint?

1. Package com. jiubang. Android. gesturetest;
3. Import Android. App. activity;
4. Import Android. OS. Bundle;
5. Import Android. util. log;
6. Import Android. View. gesturedetector;
7. Import Android. View. motionevent;
8. Import Android. View. view;
9. Import Android. View. gesturedetector. simpleongesturelistener;
   
10. Import Android. View. View. ontouchlistener;
11. Import Android. widget. Button;
13. Public class gestureactivity extends Activity
    
14. Implements ontouchlistener
15. {
16. Private button mbutton = NULL;
    
17. Gesturedetector mgesture = NULL;
19. /** Called when the activity is first created .*/
    
20. @ Override
21. Public void oncreate (bundle savedinstancestate ){
    
22. Super. oncreate (savedinstancestate );
23. Setcontentview (R. layout. Main );
25. Log. I ("test", "oncreate ");
    
26. Mbutton = (button) findviewbyid (R. Id. button1 );
27. Mbutton. setontouchlistener (this );
    
28. Mgesture = new gesturedetector (this,
    New gesturelistener ());
29. }
31. @ Override
32. Public Boolean ontouch (view V, motionevent event)
    
33. {
34. // Todo auto-generated method stub
    
35. Return mgesture. ontouchevent (event );
    
36. }
38. Class gesturelistener extends simpleongesturelistener
    
39. {
41. @ Override
42. Public Boolean ondoubletap (motionevent E)
    
43. {
44. // Todo auto-generated method stub
    
45. Log. I ("test", "ondoubletap ");
    
46. Return super. ondoubletap (E );
    
47. }
49. @ Override
50. Public Boolean ondown (motionevent E)
    
51. {
52. // Todo auto-generated method stub
    
53. Log. I ("test", "ondown ");
    
54. Return super. ondown (E );
55. }
57. @ Override
58. Public Boolean onfling (motionevent E1, motionevent E2,
    Float velocityx,
59. Float velocityy)
    
60. {
61. // Todo auto-generated method stub
    
62. Log. I ("test", "onfling: velocityx =" + velocityx +
    "Velocityy" + velocityy );
63. Return super. onfling (E1, E2, velocityx, velocityy );
    
64. }
66. @ Override
67. Public void onlongpress (motionevent E)
    
68. {
69. // Todo auto-generated method stub
    
70. Log. I ("test", "onlongpress ");
    
71. Super. onlongpress (E );
72. }
74. @ Override
75. Public Boolean onscroll (motionevent E1, motionevent E2,
    
76. Float distancex, float distancey)
    
77. {
78. // Todo auto-generated method stub
    
79. Log. I ("test", "onscroll: distancex =" + distancex +
    "Distancey =" + distancey );
80. Return super. onscroll (E1, E2, distancex, distancey );
    
81. }
83. @ Override
84. Public Boolean onsingletapup (motionevent E)
    
85. {
86. // Todo auto-generated method stub
    
87. Log. I ("test", "onsingletapup ");
    
88. Return super. onsingletapup (E );
    
89. }
91. }
92. }