Android Touch event Transfer Mechanism

Mainactivity is as follows:

Package cn. c; import android. OS. bundle; import android. app. activity; import android. view. menu; // The first test // The output result is as follows: // call onInterceptTouchEvent () in MyFrameLayout // onInterceptTouchEvent () in MyFrameLayout returns by default: false // call onTouchEvent () in the Custom Button // The onTouchEvent () returned by default in the Custom Button is: true // onTouchEvent () ---> ACTION_DOWN // call onInterceptTouchEvent () in MyFrameLayout // onInterceptTouchEvent () in MyFrameLayout () The default value returned is false // call onTouchEvent () in the Custom Button // onTouchEvent () in the Custom Button. The default value returned is true // onTouchEvent () in the Custom Button () ---> ACTION_UP // Summary: // 1 This is the output after you click the Custom Button quickly. We can see: // onTouchEvent () in the Button () the onInterceptTouchEvent () // 2 will be called before ACTION_DOWN // and ACTION_UP. If the time is long, the following code will be repeatedly executed between ACTION_DOWN and ACTION_UP: // call onInterceptTouchEvent () in MyFrameLayout // onInterceptTouchEvent () in MyFrameLayout returns false by default. // call o in Custom Button NTouchEvent () // The onTouchEvent () returned by default in the Custom Button is true // 3 from this we can see: // onInterceptTouchEvent () the default returned is false // No interception. // The onTouchEvent () of the Custom Button is returned as true by default. // you can respond to the click event. // 4. Sorting: The Custom Button responds to onTouchEvent () because no interception is detected () // so in MyFrameLayout, The onTouchEvent () is not returned // The second test // onInterceptTouchEvent (MotionEvent ev) returns true // that is, blocking // at this time, the Custom Button does not respond to onTouchEvent () // but at this time, MyFrameLayout will respond to onTouchEvent () // but only responds to ACTION_DOWN and does not respond to ACTIO N_UP // because onTouchEvent () in MyFrameLayout returns false by default. // to make MyFrameLayout respond to onTouchEvent () and execute // ACTION_DOWN and ACTION_UP. in MyFrameLayout, The onTouchEvent () in // returns true // The third test // returns false to onInterceptTouchEvent () in MyFrameLayout (default) // make the onTouchEvent () in the Custom Button return false // The execution result is: onTouchEvent () in the Custom Button only executes ACTION_DOWN // The onTouchEvent () in the Button is not executed () ACTION_UP. then, // executes onTouchEvent () in MyFrameLayout and only responds to ACTION_DO. WN. // Why: onTouchEvent () in MyFrameLayout only responds to ACTION_DOWN ??? // As mentioned above: onTouchEvent () in MyFrameLayout returns false by default. // If the returned value is changed to true, // ACTION_DOWN and ACTION_UP in onTouchEvent () in MyFrameLayout will be executed. // Test Summary: // 1 onInterceptTouchEvent () in MyFrameLayout returns false by default // that is, it does not intercept, so that the click event is easily passed to onTouchEvent () in View () // 2 The onTouchEvent () in MyFrameLayout returns false by default. // 3 The onTouchEvent () in the Custom View returns true by default, so that OnTouch () can be returned multiple times () event // reference: // http://blog.csdn.net/psh24053/article/details/7523486// http://blog.csdn.net/android_tutor/article/details/7193090public class MainActivity extends Activity {@ Override public void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. main) ;}@ Override public boolean onCreateOptionsMenu (Menu menu) {getMenuInflater (). inflate (R. menu. main, menu); return true ;}}

Myframelayout is as follows:

Package cn. c; import android. content. context; import android. util. attributeSet; import android. view. keyEvent; import android. view. motionEvent; import android. widget. frameLayout; public class MyFrameLayout extends FrameLayout {public MyFrameLayout (Context context, AttributeSet attrs) {super (context, attrs) ;}@ Overridepublic boolean dispatchKeyEvent (KeyEvent event) {// TODO Auto-generated method stubreturn super. dispatchKeyEvent (event);} // override from ViewGroup @ Overridepublic boolean onInterceptTouchEvent (MotionEvent ev) {System. out. println ("calling onInterceptTouchEvent ()" In MyFrameLayout); System. out. println ("onInterceptTouchEvent () in MyFrameLayout returns:" + super. onInterceptTouchEvent (ev); // The following sentence corresponds to the first test return super. onInterceptTouchEvent (ev); // The following sentence corresponds to the second test // return true; // The following sentence corresponds to the third test // return super. onInterceptTouchEvent (ev);} // override from View // However, ViewGroup is a subclass of View @ Overridepublic boolean onTouchEvent (MotionEvent event) {// For the second test System. out. println ("calling onTouchEvent ()" In MyFrameLayout); System. out. println ("onTouchEvent () in MyFrameLayout returns:" + super. onInterceptTouchEvent (event); switch (event. getAction () {case MotionEvent. ACTION_DOWN: System. out. println ("onTouchEvent () ---> ACTION_DOWN" in MyFrameLayout); break; case MotionEvent. ACTION_UP: System. out. println ("onTouchEvent () ---> ACTION_UP" in MyFrameLayout); default: break;} return super. onTouchEvent (event );}}

Mybutton is as follows:

Package CN. c; import android. content. context; import android. util. attributeset; import android. view. motionevent; import android. widget. button; public class mybutton extends button {public mybutton (context, attributeset attrs) {super (context, attrs ); // todo auto-generated constructor stub} @ overridepublic Boolean ontouchevent (motionevent event) {system. out. println ("calling ontouchevent ()" In a Custom button); system. out. println ("ontouchevent () in a Custom button returns:" + super. ontouchevent (event); Switch (event. getaction () {Case motionevent. action_down: system. out. println ("ontouchevent () ---> action_down"); break; Case motionevent. action_up: system. out. println ("ontouchevent () ---> action_up" in the Custom button); default: break;} // The following sentence corresponds to the first, second test return Super. ontouchevent (event); // The following sentence corresponds to the third test // return false ;}}

Main. XML is as follows:

<! -- Place a custom control in the custom Layout --> <CN. c. myframelayout xmlns: Android = "http://schemas.android.com/apk/res/android" Android: layout_width = "match_parent" Android: layout_height = "match_parent"> <CN. c. mybutton Android: layout_width = "200dip" Android: layout_height = "200dip" Android: text = "Custom button" Android: textcolor = "@ Android: color/Black "/> </CN. c. myframelayout>