Android的網頁視圖回壓點擊回去雙擊退出

Question

好傢伙我試圖讓在網頁視圖後退按鈕回去當按下一個時間和警報完成的活動按兩次當

問題是，當我嘗試雙擊它運行，就好像我點擊了一個..他不期望雙擊運行時間

謝謝！

代碼

 public void onBackPressed() 
    { 
     if (back_pressed + 1000 > System.currentTimeMillis()){ 
     new AlertDialog.Builder(this) 
      .setIcon(R.drawable.ic_launcher) 
      .setTitle("Esmalteria Cariúcha") 
      .setMessage("Sair do Sistema?") 
      .setPositiveButton("Sim", new DialogInterface.OnClickListener() 
      { 
       @Override 
       public void onClick(DialogInterface dialog, int which) { 
        finish();  
       } 

      }) 
      .setNegativeButton("Não", null) 
      .show(); 
     } 
     else{ 
      if(webview.canGoBack()){ 
       webview.goBack(); 
      } 
     } 
     back_pressed = System.currentTimeMillis(); 
} 

Answer 1

儘量讓這一點，看看這對你的作品，

boolean doubleBackToExitPressedOnce; 

@Override 
public void onBackPressed() { 
    Log.i(TAG, "onBackPressed"); 

    if (doubleBackToExitPressedOnce) { 
     Log.i(TAG, "double click"); 
     new AlertDialog.Builder(this) 
       .setIcon(R.drawable.ic_launcher) 
       .setTitle("Esmalteria Cariúcha") 
       .setMessage("Sair do Sistema?") 
       .setPositiveButton("Sim", 
         new DialogInterface.OnClickListener() { 
          @Override 
          public void onClick(DialogInterface dialog, 
            int which) { 
           finish(); 
          } 

         }).setNegativeButton("Não", null).show(); 
     return; 
    } else { 
     Log.i(TAG, "single click"); 
     if (webview.canGoBack()) { 
      Log.i(TAG, "canGoBack"); 
      webview.goBack(); 
     } else { 
      Log.i(TAG, "nothing to canGoBack"); 
     } 
    } 

    this.doubleBackToExitPressedOnce = true; 
    if (getApplicationContext() == null) { 
     return; 
    } else { 
     Toast.makeText(this, "Please click BACK again to exit", 
       Toast.LENGTH_SHORT).show(); 
    } 
    new Handler().postDelayed(new Runnable() { 

     @Override 
     public void run() { 
      doubleBackToExitPressedOnce = false; 
     } 
    }, 2000); 
} 

Answer 2

試試這個

private WebView view; 
private String urlhome = "http://localhost/Default.aspx"; 
private static String currenturl = ""; 
private Boolean close_app = false; 

public boolean onKeyDown(int keyCode, KeyEvent event) { 
    if (keyCode == KeyEvent.KEYCODE_BACK) { 
     if (view.canGoBack()) { 
      String url = view.getUrl(); 

      if (url.equalsIgnoreCase(urlhome)) { 
       if (close_app) { 
        // pressed twice 
        finish(); 
       } else { 
        Toast.makeText(this, "Press Back again to Exit.", 
          Toast.LENGTH_SHORT).show(); 
        close_app = true; 
        new Handler().postDelayed(new Runnable() { 
         @Override 
         public void run() { 
          close_app = false; 
         } 
        }, 3 * 1000); 

        return true; 
       } 
      } else { 
       view.goBack(); //method goback() 
       return true; 
      } 
     } else { 
      String url = view.getUrl(); 
      if (url.equalsIgnoreCase(urlhome)) { 
       if (close_app) { 
        // pressed twice 
        finish(); 
       } else { 
        Toast.makeText(this, "Press Back again to Exit.", 
          Toast.LENGTH_SHORT).show(); 
        close_app = true; 
        new Handler().postDelayed(new Runnable() { 
         @Override 
         public void run() { 
          close_app = false; 
         } 
        }, 3 * 1000); 

        return true; 
       } 
      }else { 
       view.loadUrl(urlhome); 
       currenturl = urlhome; 
       return true; 
      } 
     } 
    } 
    return super.onKeyDown(keyCode, event); 
}