Android里面编写退出主程序的提示代码

废话不多说，先在AndroidManifest.xml文件中添加<uses-permission android:name="android.permission.RESTART_PACKAGES" />
这行代码，然后在自己的Activity重写onKeyDown()方法。具体如下：

@Override

public boolean onKeyDown(int keyCode, KeyEvent event) {

if(keyCode==KeyEvent.KEYCODE_BACK&&event.getRepeatCount()==0){
            AlertDialog.Builder alertbBuilder=new AlertDialog.Builder(this);
            alertbBuilder.setTitle("真的要离开？").setMessage("你确定要离开？").setPositiveButton("确定", new DialogInterface.OnClickListener() {

                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                            //结束这个Activity
                   
int nPid = android.os.Process.myPid();
                   
android.os.Process.killProcess(nPid);
                    }
            }).setNegativeButton("取消", new DialogInterface.OnClickListener() {

                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                            dialog.cancel();

                    }
            }).create();
            alertbBuilder.show();

    }

return true;

}


至此完成。程序可以真正的退出，而不是在后台运行。