android广播加权限,解决在BroadcastReceiver（广播接受者）中不能添加AlertDialog（对话框）的问题（android.view.WindowManager$BadToken...

在BroadcastReceiver，当我们创建一个AlertDialog并show出来的时候，出现了下面的错误：

12-24 14:10:57.025: E/AndroidRuntime(17600): java.lang.RuntimeException: Unable to start receiver com.ustc.broadcastreceiver.ForceOfflineReceiver: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application

下面的方法可以解决：

第一步：

在调用show方法之前，设置下面的属性：

dialog.getWindow()

.setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);再次运行，发现程序又挂了：

12-24 14:15:22.793: E/AndroidRuntime(17979): java.lang.RuntimeException: Unable to start receiver com.ustc.broadcastreceiver.ForceOfflineReceiver: android.view.WindowManager$BadTokenException: Unable to add window [email protected] --

permission denied for this window type

这个一看就知道了，权限拒绝，需要添加权限：

第二步：

在清单文件中添加权限：

这样运行就OK了，我的代码如下：

package com.ustc.broadcastreceiver;

import android.app.AlertDialog;

import android.app.AlertDialog.Builder;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.DialogInterface;

import android.content.DialogInterface.OnClickListener;

import android.content.Intent;

import android.view.WindowManager;

public class ForceOfflineReceiver extends BroadcastReceiver {

@Override

public void onReceive(final Context context, Intent intent) {

AlertDialog.Builder builder = new Builder(context);

builder.setTitle("提示");

builder.setMessage("强制下线");

builder.setCancelable(false);

builder.setPositiveButton("ok", new OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

ActivityCollector.finishAll();

Intent intent = new Intent(context, LoginActivity.class);

intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

context.startActivity(intent);

}

});

AlertDialog dialog = builder.create();

dialog.getWindow()

.setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);

dialog.show();

}

}

原文：http://blog.youkuaiyun.com/chenfuduo_loveit/article/details/42123303