Android学习之Broadcast的简单使用
作者:天秤心已随风去
这篇文章主要为大家详细介绍了Android学习之Broadcast的简单使用方法,具有一定的参考价值,感兴趣的小伙伴们可以参考一下
本文实例为大家分享了Android学习之Broadcast的使用方法,供大家参考,具体内容如下
实现开机启动提示网络的广播
package com.example.luobo.broadcasttest; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.Toast; public class MainActivity extends AppCompatActivity { private IntentFilter intentFilter; private NetworkChangeReceiver networkChangeReceiver; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); intentFilter = new IntentFilter();//创建一个过滤器实例 intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");//添加接收CONNECTIVITY_CHANGE消息 networkChangeReceiver = new NetworkChangeReceiver(); registerReceiver(networkChangeReceiver,intentFilter); } @Override protected void onDestroy() { super.onDestroy(); unregisterReceiver(networkChangeReceiver); } class NetworkChangeReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);//通过此方法获取ConnectivityManager实例 NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();//调用实例connectivityManager的getActiveNetworkInfo()方法获取NetworkInfo实例 if (networkInfo != null && networkInfo.isAvailable()){ Toast.makeText(context,"Network is available",Toast.LENGTH_SHORT).show(); }else { Toast.makeText(context,"Network is unavailable",Toast.LENGTH_SHORT).show(); } } } }
创建BootCompleteReceiver类
右击com.example.luobo.broadcasttest,New->Other->Broadcast,输入名字BootCompleteReceiver,勾选Enable,Exported,重写onReceive()方法。由于使用的是快捷方式创建的类,所需权限会在AndroidManifest.xml中自动注册。标签为receiver,但是还不够修改。
package com.example.luobo.broadcasttest; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.widget.Toast; public class BootCompleteReceiver extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { Toast.makeText(context,"Boot Complete",Toast.LENGTH_SHORT).show(); } }
在AndroidMaifest.xml注册权限
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.luobo.broadcasttest"> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />//注册接收网络消息广播 <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>//注册接收开机启动广播 <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"> <activity android:name=".MainActivity"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <receiver android:name=".BootCompleteReceiver" android:enabled="true" android:exported="true"> <intent-filter> <action android:name="android.intent.action.BOOT_COMPLETED"/>//开机时系统会发一条此广播 </intent-filter> </receiver> </application> </manifest>
上述在AndroidMainfest.xml中注册接收广播消息属于静态注册,在OnCreate()中注册的接收广播属于动态注册。
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。