Implementation code of exit confirmation box in Android

This is achieved by blocking and rewriting the operation of the back key: when the back key is pressed, a prompt box will pop up to choose whether to exit, if so, execute the exit code, otherwise do nothing.

Override in Mianactivity:

@Override
public void onBackPressed() {
 new AlertDialog.Builder(this)
   .setIcon(R.drawable.ic_launcher)//Here is the picture information to display the prompt box, the icon of the default androidApp I use here
   .setTitle("Confirmation dialog")
   .setMessage("Do you really want to quit?")
   .setNegativeButton("Cancel",null)
   .setPositiveButton("确认", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int which) {
     finish();
    }
   }).show();
}

 Add this code to an android program to get the back button at the end as shown in the figure: