不少应用在按下返回按键的时候能够退出该应用,并且弹出返回对话框,其实现步骤如下:
1,首先在点击返回键需要退出的界面增加成员变量
public static ArrayList<Activity> allActivity = new ArrayList<Activity>();
2,监听按键点击事件
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (event.KEYCODE_BACK == keyCode) {
exit();
}
return super.onKeyDown(keyCode, event);
}
3,关键是exit方法体的实现
private void exit(){
Dialog dialog = new AlertDialog.Builder(MainActivity.this)
.setTitle("退出").setMessage("你确定要退出吗?")
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
for (Activity ac : allActivity) {
ac.finish();
dialog.dismiss();
}
}
}).setNegativeButton("取消", null).create();
dialog.show();
}