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。
