动/静态接收系统广播

动态接收系统广播：

先创建IntentFilter作为广播内容，再写一个继承于BroadcastReceiver的类作为接收器，然后注册接收器，最后在AndroidManifest.xml添加相关许可。代码如下：

import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.widget.Toast;public class Broadcast extends AppCompatActivity {    NetworkChangeReceiver networkChangeReceiver;    @Override    protected void onCreate(Bundle savedInstanceState){        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        IntentFilter intentFilter=new IntentFilter();        intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");  //设置为网络变化活动        networkChangeReceiver=new NetworkChangeReceiver();        registerReceiver(networkChangeReceiver,intentFilter);   //注册广播接收器，第一个参数为BroadcastReceiver类，第二个参数为广播内容    }    @Override    protected void onDestroy(){        super.onDestroy();        unregisterReceiver(networkChangeReceiver);    }}class NetworkChangeReceiver extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent){        Toast.makeText(context,"网络发生了改变！",Toast.LENGTH_SHORT).show();    }}

AndroidManifest.xml

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

静态注册实现开机启动：

在一个独立的类中继承BroadcastReceiver写覆盖方法执行收到广播后的操作，然后在AndroidManifest中写<receiver和<use-permission

Broadcast.class

import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.widget.Toast;public class Broadcast extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent){        Toast.makeText(context,"Boot Completed！",Toast.LENGTH_SHORT).show();    }}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="mole.test">    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:roundIcon="@mipmap/ic_launcher_round"        android:supportsRtl="true"        android:theme="@style/AppTheme">        <use-permission android:name="android.permission.RECEIVER_BOOT_COMPLETED"/>        <receiver            android:name=".Broadcast"            android:enabel="true"             android:exported="true">            <intent-filter>                <action android:name="android.intent.action.BOOT_COMPLETED"/>            </intent-filter>        </receiver>        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>