onBackPressed（）沒有被調用

Question

我有一個活動「DashboardActivity」（不是主要活動），我想要捕獲BACK按鈕以詢問他們是否要註銷（因爲BACK通常會將您帶到登錄屏幕） 。

我已經試過

public void onBackPressed() { 
    // ask if they want to logout..... 
    logOutIfTheyReallyWantTo(); 

    //super.onBackPressed(); 
} 

但在調試器中測試這一點，似乎並沒有在所有的打碼。

然後我試圖添加

@Override 
public boolean onKeyDown(int keyCode, KeyEvent event) { 
    if (android.os.Build.VERSION.SDK_INT < android.os.Build.VERSION_CODES.ECLAIR 
      && keyCode == KeyEvent.KEYCODE_BACK 
      && event.getRepeatCount() == 0) { 
     // Take care of calling this method on earlier versions of 
     // the platform where it doesn't exist. 
     onBackPressed(); 
    } 

    return super.onKeyDown(keyCode, event); 
} 

這也證明了是浪費時間。

最後我想

@Override 
public boolean onKeyLongPress(int keyCode, KeyEvent event) { 
    if (keyCode == KeyEvent.KEYCODE_BACK) { 
     // a long press of the call key. 
     // do our work, returning true to consume it. by 
     // returning true, the framework knows an action has 
     // been performed on the long press, so will set the 
     // canceled flag for the following up event. 
     return true; 
    } 
    return super.onKeyLongPress(keyCode, event); 
} 

但調試檢測沒有​​。 logcat中只顯示

05-29 12:22:59.040: D/NetdConnector(14366): RCV <- {217 0} 
    05-29 12:22:59.040: D/NetdConnector(14366): RSP <- {217 0} 
    05-29 12:23:04.743: V/processReply(32759): sr0857000000 
    05-29 12:23:07.673: W/KeyCharacterMap(32759): No keyboard for id 0 
    05-29 12:23:07.673: W/KeyCharacterMap(32759): Using default keymap: /system/usr/keychars/qwerty.kcm.bin 
    05-29 12:23:07.907: V/Dashboard(32759): Pause 
    05-29 12:23:07.915: I/ComfortActivity(32759): start 
    05-29 12:23:07.915: V/ComfortActivity(32759): Resume 
    05-29 12:23:08.032: D/dalvikvm(14430): GC_EXPLICIT freed 92K, 52% free 3322K/6791K, external 5633K/7003K, paused 77ms 
    05-29 12:23:08.329: I/DashboardActivity(32759): stop 
    05-29 12:23:08.829: V/processReply(32759): sr0856000000 

似乎有大約這許多問題，到目前爲止，我已經嘗試了所有的建議，我可以找到，但沒有運氣。

----在答覆問題....

void logOutIfTheyReallyWantTo() 
{ 
    AlertDialog.Builder alert = new AlertDialog.Builder(this); 
    alert.setTitle("Log out?"); 
    alert.setMessage("Do you really want to log out?"); 

    //AlertDialog loginPrompt = alert.create(); 

    alert.setPositiveButton("OK", new DialogInterface.OnClickListener() 
    { 

     public void onClick(DialogInterface dialog, int which) { 
      ((ComfortApp) getApplicationContext()).soundClick(); 

      getComms().logout(true); 
      Intent intent = new Intent(DashboardActivity.this, ConfigurationActivity.class); 
      startActivityForResult(intent, 0); 
     } 
    }); 
    alert.setNegativeButton("Cancel", new DialogInterface.OnClickListener() 
    { 

     public void onClick(DialogInterface dialog, int which) { 
      // TODO Auto-generated method stub 
      // just like Perry the Platypus.... 
      // don't do much 
      ((ComfortApp) getApplicationContext()).soundClick(); 
     } 
    }); 
    alert.show(); 

} 

Answer 1

嗨請嘗試以下代碼..

@Override 
    public void onBackPressed() { 
     AlertDialog.Builder alertbox = new AlertDialog.Builder(this); 
     alertbox.setMessage("Are you sure logout?"); 
     alertbox.setTitle("Logout"); 
     alertbox.setNeutralButton("Yes", new DialogInterface.OnClickListener() { 
      public void onClick(DialogInterface arg0, int arg1) { 
       showDialog(0); 
       new Thread() { 
        public void run() { 
         startActivity(new Intent(DashBoard.this, Login.class)); 
         DashBoard.super.onBackPressed(); 
        } 
       }.start(); 
      } 
     }); 
     alertbox.setNegativeButton("No", new DialogInterface.OnClickListener() { 
      public void onClick(DialogInterface arg0, int arg1) { 
      } 
     }); 
     alertbox.show(); 
    } 

Answer 2

覆蓋finish()活動中捕捉退出。如果你不想退出，請不要撥打super。

@Override 
    public void finish() 
    { 
     if(!wantToExit) 
     { 
      super.finish(); 
     } 
     else 
     { 
      logOutIfTheyReallyWantTo(); 
     } 
    } 

的onBackPressed()上Activity默認實現 -

public void onBackPressed() 
    { 
     finish(); 
    }