在activity中屏蔽home鍵的方法

在activity中加上下面這段代碼就可以屏蔽home

Java代碼 

1. @Override  
2.     public boolean onKeyDown(int keyCode, KeyEvent event)   
3.     {   
4.         // TODO Auto-generated method stub   
5.         // 按下鍵盤上返回按鈕   
6.   
7.         if (keyCode == KeyEvent.KEYCODE_HOME)   
8.         {   
9.                         Log.i("TAG","home");   
10.             System.exit(0);   
11.             return true;   
12.         }   
13.         else  
14.             return super.onKeyDown(keyCode, event);   
15.   
16.     }  

@Override

public boolean onKeyDown(int keyCode, KeyEvent event)

{

  // TODO Auto-generated method stub

  // 按下鍵盤上返回按鈕

 

  if (keyCode == KeyEvent.KEYCODE_HOME)

  {

                        Log.i("TAG","home");

   System.exit(0);

   return true;

  }

  else

   return super.onKeyDown(keyCode, event);

 

}

 

前提是，要重寫onAttachedToWindow()這個方法。

 

Java代碼 

1. @Override  
2.     public void onAttachedToWindow()   
3.     {   
4.         this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG);   
5.         super.onAttachedToWindow();   
6.     }  

@Override

public void onAttachedToWindow()

{

  this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG);

  super.onAttachedToWindow();

}

 

 

因為android系統自己對home鍵在PhoneWindowManager中做了處理，不會返回到上層應用。查看源代碼：

\frameworks\policies\base\phone\com\android\internal\policy\impl\PhoneWindowManager.java 1089行

Java代碼 

1. if (code == KeyEvent.KEYCODE_HOME) {   
2.             // If a system window has focus, then it doesn't make sense   
3.             // right now to interact with applications.   
4.             WindowManager.LayoutParams attrs = win != null ? win.getAttrs() : null;   
5.             if (attrs != null) {   
6.                 final int type = attrs.type;   
7.                 if (type == WindowManager.LayoutParams.TYPE_KEYGUARD   
8.                         || type == WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG) {   
9.                     // the "app" is keyguard, so give it the key   
10.                     return false;   
11.                 }   
12.                 final int typeCount = WINDOW_TYPES_WHERE_HOME_DOESNT_WORK.length;   
13.                 for (int i=0; i<typeCount; i++) {   
14.                     if (type == WINDOW_TYPES_WHERE_HOME_DOESNT_WORK[i]) {   
15.                         // don't do anything, but also don't pass it to the app   
16.                         return true;   
17.                     }   
18.                 }   
19.             }  

if (code == KeyEvent.KEYCODE_HOME) {

            // If a system window has focus, then it doesn't make sense

            // right now to interact with applications.

            WindowManager.LayoutParams attrs = win != null ? win.getAttrs() : null;

            if (attrs != null) {

                final int type = attrs.type;

                if (type == WindowManager.LayoutParams.TYPE_KEYGUARD

                        || type == WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG) {

                    // the "app" is keyguard, so give it the key

                    return false;

                }

                final int typeCount = WINDOW_TYPES_WHERE_HOME_DOESNT_WORK.length;

                for (int i=0; i<typeCount; i++) {

                    if (type == WINDOW_TYPES_WHERE_HOME_DOESNT_WORK[i]) {

                        // don't do anything, but also don't pass it to the app

                        return true;

                    }

                }

            }

 注意，activity中重寫onAttachedToWindow（）方法需要api 5以上