Question

我想在用户点击此活动中的退出Button时发出提醒。如何实现这一目标？

public class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mainactivity);
        addListenerOnButton();
    }

    public void addListenerOnButton() {

        final Context context = this;

        Button button1 = (Button)findViewById(R.id.button1);
        Button button2 = (Button)findViewById(R.id.button2);
        Button exit = (Button) findViewById(R.id.button4);

        button1.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                Intent intent = new Intent(context, A.class);
                startActivity(intent);

            }

        });
        button2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                Intent intent = new Intent(context, B.class);
                startActivity(intent);

            }

        });
        exit.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                // TODO Auto-generated method stub
                moveTaskToBack(true);
        });


    }
    public void onBackPressed() {
        new AlertDialog.Builder(this)
                .setMessage("Are You Sure?")
                .setCancelable(false)
                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        MainActivity.this.finish();
                    }
                })
                .setNegativeButton("No", null)
                .show();
    }

    @Override public boolean onCreateOptionsMenu(Menu menu) {
        return true;
    }

}

Answer 1

创建一个名为exitDialog()的方法，如下所示：

public void exitDialog() {
    new AlertDialog.Builder(this)
            .setMessage("Are You Sure?")
            .setCancelable(false)
            .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    MainActivity.this.finish();
                }
            })
            .setNegativeButton("No", null)
            .show();
}

而不是在onBackPressed()方法和退出按钮中使用它，例如：

public void onBackPressed() {
    exitDialog();
    super.onBackPressed();
}

和

exit.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
        exitDialog();
});

Answer 2

只需调用你的按钮clicklistener你的onBackPressed（）方法！

当您按下后退键物理按钮时，您会得到相同的警报!!!

exit_button.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            onBackPressed();

        }
    });

按下退出按钮时发出警报

2 个答案: