实现步骤:
1、重写onBackPressed方法
2、去掉原有的父类方法
3、编写确认对话框
4、在确定事件后调用finish()方法来结束程序
package com.example.catalogin;
import android.content.DialogInterface;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
public void onBackPressed() {
new AlertDialog.Builder( this )
.setIcon( R.drawable.apple)
.setTitle( "确认对话框" )
.setMessage( "你确定要退出?" )
.setNegativeButton( "取消",null )
.setPositiveButton( "确定", new DialogInterface.OnClickListener() {