Android实战开发篇 监听广播唤起Activity(活动)Dialog弹窗的方案

Posted 2021-08-13 彭老希

一、弹窗权限

<uses-permissionandroid:name="android.permission.SYSTEM_ALERT_WINDOW" />

二、广播唤起（活动）Activity

//关键点：需要添加 Intent.FLAG_ACTIVITY_NEW_TASK
  intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

public class MyAppReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
		  String action = intent.getAction();
		 // XXXXXActivity : 唤起的目标Activity活动 
		Intent intent = new Intent(context,XXXXXActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        context.startActivity(intent);
	}

三、广播唤起（弹窗）Dialog / Dialog.Bulider

dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT)

public class XXXXReceiver extends BroadcastReceiver{
 
    @Override
    public void onReceive(final Context context, Intent intent){
        AlertDialog.Builder builder = new AlertDialog.Builder(context);
        builder.setTitle("欢迎来到CSDN博客");
        builder.setMessage("欢迎关注彭老希");
        builder.setCancelable(false);
        builder.setPositiveButton("Welcome", new DialogInterface.OnClickListener()
        {
            @Override 
            public void onClick(DialogInterface dialog, int which){
                Intent intent = new Intent(context, LoginActivity.class);
                //在广播接受者中启动活动需要添加这个标志
                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
                context.startActivity(intent);
            }
        });
        AlertDialog dialog = builder.create();
        dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT); //需要设置AlertDialog的类型，保证在广播接收者中可以正常弹出
        dialog.show();
    }
}

其他方式

正常弹出AlertDialog的流程如下：

new AlertDialog.Builder(context).setTitle("在BroadcastReceiver里弹出AlertDialog").show();

但是其实AlertDialog似乎只能在activity中弹出为了解决在BroadcastReceiver里弹出AlertDialog这个问题，我们可以这样做：

AlertDialog alertDialog=new AlertDialog.Builder(context).create();
alertDialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
alertDialog.show();

最后还要在AndroidManifest.xml文件中加入以下两句话：

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/> 
<uses-permission android:name="android.permission.SYSTEM_OVERLAY_WINDOW"/>