Android 安卓：截取回键

因为back键会破坏我的应用程序，所有数据都会丢失，所以我需要截取它来询问用户这是否真的是他想要的

我想到了以下结构：

@Override
    public boolean onKeyDown(int keyCode, KeyEvent event)  
    {    
        if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) 
        { 
         // ask user if he really wants to exit
         // no --> return true;
         // yes --> return super.onKeyDown(keyCode, event);
         //manually entering either of the return values works fine
        }   
    return super.onKeyDown(keyCode, event);
    }

我想通过一个提醒对话框来实现的“询问用户”部分。现在我的问题是显示了警报对话框，但在显示警报对话框时onKeyDown方法一直运行到最后，而在警报对话框中，我不知道如何告诉系统传递正确的返回值

我想的完整代码是

@Override
    public boolean onKeyDown(int keyCode, KeyEvent event)  
    {    
        if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) 
        { 

            alertDialog = new AlertDialog.Builder(this).create();
            alertDialog.setTitle("Tile");
            alertDialog.setMessage("data lost, are you sure?");

            alertDialog.setButton(-1, getString(R.string.yes), new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which) 
                {
                    return;
                    //I only can return without a boolean value here.                   }
            });

            alertDialog.setButton(-2, getString(R.string.no), new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which) 
                {
                    return;
                }
            });

            alertDialog.show();
        }   
        return super.onKeyDown(keyCode, event);
    }

---

谢谢，A.

alertDialog.show（）；当用户按下返回按钮时，应在单击“无”按钮的范围内调用对话框

onKeyDown现在已被处理，因此返回true

现在显示您的对话框

当你按下yes时，你想模仿后退按钮，这是什么；做

当您按“否”时，您只需关闭对话框，活动将继续

你会想要这个：

 @Override
public boolean onKeyDown(int keyCode, KeyEvent event)  
{    
    if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) 
    { 

        alertDialog = new AlertDialog.Builder(this).create();
        alertDialog.setTitle("Tile");
        alertDialog.setMessage("data lost, are you sure?");

        alertDialog.setButton(-1, getString(R.string.yes), new DialogInterface.OnClickListener()
        {
            @Override
            public void onClick(DialogInterface dialog, int which) 
            {
                finish(); // or yourContext.finish();
                //I only can return without a boolean value here.                   
            }
        });

        alertDialog.setButton(-2, getString(R.string.no), new DialogInterface.OnClickListener()
        {
            @Override
            public void onClick(DialogInterface dialog, int which) 
            {
                // do nothing dialog will dismiss
            }
        });

        alertDialog.show();
        return true; //meaning you've dealt with the keyevent
    }   
    return super.onKeyDown(keyCode, event);
}

删除返回super.onKeyDown（keyCode，event）；