本文實例為大家分享了Android學習之Broadcast的使用方法，供大家參考，具體內容如下
實現開機啟動提示網絡的廣播
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();//創建一個過濾器實例 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);//通過此方法獲取ConnectivityManager實例 NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();//調用實例connectivityManager的getActiveNetworkInfo()方法獲取NetworkInfo實例 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(); } } }}創建BootCompleteReceiver類
右擊com.example.luobo.broadcasttest，New->Other->Broadcast,輸入名字BootCompleteReceiver，勾選Enable，Exported,重寫onReceive()方法。由于使用的是快捷方式創建的類，所需權限會在AndroidManifest.xml中自動注冊。標簽為receiver，但是還不夠修改。
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注冊權限
<?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" />//注冊接收網絡消息廣播 <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>//注冊接收開機啟動廣播 <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"/>//開機時系統會發一條此廣播 </intent-filter> </receiver> </application></manifest>
上述在AndroidMainfest.xml中注冊接收廣播消息屬于靜態注冊，在OnCreate()中注冊的接收廣播屬于動態注冊。
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持VEVB武林網。
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