按下返回键时的对话框

Question

按下返回键时的对话框

3

我在我的游戏中有一个alertDialog，当我按下设备的backkey时，会出现对话框。如果我按下"Quit"，我的游戏将关闭，如果我按下"Cancle"，则会出现3秒钟的toast，3秒钟后我的游戏会重新开始。现在的问题是，当我第一次按下设备的backkey时，对话框出现了，并且我执行了一些功能，它正常工作，但是如果我再次按下"Cancel"或"Quit"之外的backkey，那么我的游戏不会恢复，直到我按下"NO"按钮。

我想要的是，如果我按下backkey，则对话框出现并且如果我再次按下backkey，则我的游戏会恢复，而不必再次显示对话框，谢谢。

以下是我的alert dialog代码:

@TargetApi(Build.VERSION_CODES.HONEYCOMB)
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {

        if (keyCode == KeyEvent.KEYCODE_BACK) {

         //  GamePanel.thread.setStoped(true);
            GamePanel.thread.setRunning(false);

// in the next line of code we also style the dialog through xml which i put in styles


            AlertDialog alertDialog = new AlertDialog.Builder(this,R.style.myBackgroundStyle).create();
            alertDialog.setTitle("Exit Alert");
            alertDialog.setMessage("Do you really want to exit the Game?");
            alertDialog.setButton("Quit", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    //Best way is firstly use finish() and after that use System.exit(0) to clear static variables. It will give you some free space.
                    // A lot of applications leave working processes and variables what makes me angry. After 30 minutes of using memory is full and i have to run Task Manager - Lvl 2 clear memory
                    finish();
                    System.exit(0);
                    return;

                }
            });
            alertDialog.setButton2("Cancle", new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {

                            // dialog.cancel();
                            // GamePanel.thread.resume();
                            dialog.dismiss();
                            // When user press the "Cancle" button then game resume for 3 seconds then start again
                            // Here is the Code of the toasts and each toast appear with delay of one second.

                            toast = new Toast(Game.this);
                            TextView textView=new TextView(Game.this);
                            textView.setTextColor(Color.DKGRAY);
                            textView.setBackgroundColor(Color.TRANSPARENT);
                            textView.setTextSize(60);
                            textView.setText("READY!");
                            toast.setGravity(Gravity.CENTER_VERTICAL, 0, 0);

                            toast.setView(textView);
                            toast.show();

                            new Handler().postDelayed(new Runnable() {
                                @Override
                                public void run() {
                                    // show toast 2.
                                    toast = new Toast(Game.this);
                                    TextView textView = new TextView(Game.this);
                                    textView.setTextColor(Color.DKGRAY);
                                    textView.setBackgroundColor(Color.TRANSPARENT);
                                    textView.setTextSize(140);
                                    textView.setText("3");
                                    // textView.setText("done!");
                                    toast.setGravity(Gravity.CENTER_VERTICAL, 0, 0);

                                    toast.setView(textView);
                                    toast.show();
                                }
                            }, 2500);


                            new Handler().postDelayed(new Runnable() {
                                @Override
                                public void run() {
                                    // show toast 2.
                                    toast = new Toast(Game.this);
                                    TextView textView = new TextView(Game.this);
                                    textView.setTextColor(Color.DKGRAY);
                                    textView.setBackgroundColor(Color.TRANSPARENT);
                                    textView.setTextSize(140);
                                    textView.setText("2");
                                    toast.setGravity(Gravity.CENTER_VERTICAL, 0, 0);

                                    toast.setView(textView);
                                    toast.show();
                                }
                            }, 5000);

                            new Handler().postDelayed(new Runnable() {
                                @Override public void run() {
                                    toast = new Toast(Game.this);
                                    TextView textView=new TextView(Game.this);
                                    textView.setTextColor(Color.DKGRAY);
                                    textView.setBackgroundColor(Color.TRANSPARENT);
                                    textView.setTextSize(140);
                                    textView.setText("1");
                                    toast.setGravity(Gravity.CENTER_VERTICAL, 0, 0);

                                    toast.setView(textView);
                                    toast.show();

                                }
                            }, 7500);

                            new Handler().postDelayed(new Runnable() {
                                @Override
                                public void run()
                                    GamePanel.thread.setRunning(true);
                                }
                            }, 10000);


                            return;
                        }
                    }

            );
            alertDialog.show();

            return true;
        }
        return super.onKeyDown(keyCode, event);
    }

}

- Mirza Zeeshan

1个回答

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- Buddy · Accepted Answer

您需要为对话框设置一个 OnKeyListener，并检查是否按下了返回键。

以下是适合您需求的示例代码，您需要按照以下方式修改您的代码：

AlertDialog alertDialog = new AlertDialog.Builder(this,R.style.myBackgroundStyle).create();
        alertDialog.setTitle("Exit Alert");
        alertDialog.setMessage("Do you really want to exit the Game?");
        alertDialog.setButton("Quit", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {
                //Best way is firstly use finish() and after that use System.exit(0) to clear static variables. It will give you some free space.
                // A lot of applications leave working processes and variables what makes me angry. After 30 minutes of using memory is full and i have to run Task Manager - Lvl 2 clear memory
                finish();
                System.exit(0);
                return;

            }
        });


//New part regarding the back key when only dialog is shown.
alertDialog.setOnKeyListener(new Dialog.OnKeyListener() {

        @Override
        public boolean onKey(DialogInterface arg0, int keyCode,
                KeyEvent event) {

            if (keyCode == KeyEvent.KEYCODE_BACK) {

                alertDialog.dismiss();
            }
            return true;
        }
    });

这仅在对话框显示时有效，因此您可以返回到活动。