Android广播的使用（自定义广播和本地广播） _的使用

于今腐草无萤火，终古垂杨有暮鸦。这篇文章主要讲述Android广播的使用（自定义广播和本地广播）相关的知识，希望能为你提供帮助。
1》自定义广播

//定义接收器
public class MyBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(context,"接收我的广播",Toast.LENGTH_LONG).show();
}
}

·//注册事件
< receiver
android:name=".MyBroadcastReceiver"//类名
android:enabled="true"
android:exported="true">
< intent-filter>
< action android:name="com.example.broadcasttext.MY_BROADCAST"/> 广播名称
< /intent-filter>
< /receiver>

//定义按钮发送广播

【Android广播的使用（自定义广播和本地广播）】

Button button=(Button)findViewById(R.id.b1);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent("com.example.broadcasttext.MY_BROADCAST");
sendBroadcast(intent);
}
});

文章图片

广播在另外的程序上进行接收，默认的发送方式是标准广播，若想发送有序广播，需要一点点修改
MainActivity.java

button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent("com.example.broadcasttext.MY_BROADCAST");
sendBroadcast(intent);
sendOrderedBroadcast(intent,null);
}
});

加入这一行代码后广播的接收就有了顺序
注册时候可以设置接收广播的优先级

< receiver
android:name=".MyBroadcastReceiver"
android:enabled="true"
android:exported="true">
< intent-filter android:priority="100">
< action android:name="com.example.broadcasttext.MY_BROADCAST"/>
< /intent-filter>
< /receiver>

优先接收到广播后就可以判断是否继续发送广播

public class MyBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(context,"接收我的广播",Toast.LENGTH_LONG).show();
abortBroadcast();
}
}

abortBroadcast(); 可以截断广播
2》本地广播
上述例子中发送的广播可以被其他程序所接受，这对安全造成了威胁，所以安卓引入了一套本地广播的体制
MainActivity.java

package com.example.guangbo;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.location.LocationManager;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.NetworkRequest;
import android.support.v4.content.LocalBroadcastManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import java.nio.channels.NetworkChannel;

public class MainActivity extends AppCompatActivity {
private IntentFilter intentFilter;
private NetworkChangeReceiver networkChangeReceiver;
//本地广播
private LocalReceiver localReceiver;
private LocalBroadcastManager localBroadcastManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//本地广播
localBroadcastManager= LocalBroadcastManager.getInstance(this);

intentFilter=new IntentFilter();
intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
networkChangeReceiver=new NetworkChangeReceiver();
registerReceiver(networkChangeReceiver,intentFilter);
Button button=(Button)findViewById(R.id.b1);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//本地广播
Intent intent=new Intent("com.example.broadcasttext.LOCAL_BROADCAST");
localBroadcastManager.sendBroadcast(intent);

}
});
//动态注册本地广播
intentFilter=new IntentFilter();
intentFilter.addAction("com.example.broadcasttext.LOCAL_BROADCAST");
localReceiver=new LocalReceiver();
localBroadcastManager.registerReceiver(localReceiver,intentFilter);
}

@Override
protected void onDestroy() {
super.onDestroy();
//本地广播
localBroadcastManager.unregisterReceiver(localReceiver);
}
class NetworkChangeReceiver extends BroadcastReceiver{
@Override
public void onReceive(Context context, Intent intent) {
ConnectivityManager connectivityManager=(ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo=connectivityManager.getActiveNetworkInfo();
if(networkInfo!=null& & networkInfo.isAvailable()){
Toast.makeText(context,"网络可用",Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(context,"网络不可用",Toast.LENGTH_SHORT).show();
}

}
}
class LocalReceiver extends BroadcastReceiver{
@Override
public void onReceive(Context context, Intent intent) {

Toast.makeText(context,"接收本地广播",Toast.LENGTH_SHORT).show();

}
}
}