android-发送自定义广播

来源：互联网发布：react 引用js 编辑：程序博客网时间：2024/05/15 00:42

1.发送标准广播

1.在发送广播之前，我们还是需要先定义一个广播接收器来准备接收此广播。MyBroadcastReceiver.java

<span style="font-size:14px;">package com.king.broadcasttest;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.widget.Toast;public class MyBroadcastReceiver extends BroadcastReceiver{@Overridepublic void onReceive(Context context, Intent intent) {Toast.makeText(context, "received in MyBroadcastReceiver", Toast.LENGTH_SHORT).show();}}</span><span style="font-size:18px;"></span>

2.在AndroidManifest.xml中对这个广播接收器进行注册

<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.king.broadcasttest"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="17" />    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >        <receiver android:name=".BootCompleteReceiver">            <intent-filter>                                <action android:name="android.intent.action.BOOT_COMPLETED"/>            </intent-filter>                                <strong></receiver>          <receiver android:name=".MyBroadcastReceiver">            <intent-filter>                                <action android:name="com.king.broadcasttest.MY_BROADCAST"/>            </intent-filter>                                </receiver></strong>        <activity            android:name="com.king.broadcasttest.MainActivity"            android:label="@string/app_name" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest></span><span style="font-size:18px;"></span>

3.activity_main.xml

<span style="font-size:14px;"><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="@string/hello_world" />        <Button         android:id="@+id/button"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="send Broadcast"        /></RelativeLayout></span><span style="font-size:18px;"></span>

4.首先构建出了一个Intent对象，并把要发送的广播的值传入，然后调用了Context的sendBroadcast()方法将广播发送出去，这样所有监听com.example.broadcasttest.MY_BROADCAST这条广播的广播接收器就会收到消息。此时发出去的广播就是一条标准广播。MainActivity.java

<span style="font-size:14px;">package com.king.broadcasttest;import android.net.ConnectivityManager;import android.net.NetworkInfo;import android.os.Bundle;import android.app.Activity;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;import android.view.Menu;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.Toast;public class MainActivity extends Activity {private IntentFilter intentFilter;private NetworkChangeReceiver networkChangeReceiver;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);intentFilter = new IntentFilter();intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");networkChangeReceiver = new NetworkChangeReceiver();registerReceiver(networkChangeReceiver, intentFilter);Button button = (Button) findViewById(R.id.button);button.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View arg0) {Intent intent = new Intent("com.king.broadcasttest.MY_BROADCAST");sendBroadcast(intent);}});}class NetworkChangeReceiver extends BroadcastReceiver{@Overridepublic 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, "network is available", Toast.LENGTH_SHORT).show();}else{Toast.makeText(context, "network is unavailable", Toast.LENGTH_SHORT).show();}}}@Overrideprotected void onDestroy() {super.onDestroy();unregisterReceiver(networkChangeReceiver);}}</span>

2.发送有序广播

广播是一种可以跨进程的通信方式，这一点从前面的接收系统广播的时候就可以看出来了，用此在我们应用程序内发出的广播，其他的应用程序应该也是可以收回的，为了验证这一点，我们需要再新建一个BroadcastTest2项目。

1.用于接收上一个demo的自定义广播。AnotherBroadcastReceiver.java

<span style="font-size:14px;">package com.king.broadcasttest2;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.widget.Toast;public class AnotherBroadcastReceiver extends BroadcastReceiver {@Overridepublic void onReceive(Context context, Intent intent) {Toast.makeText(context, "received in AnotherBroadcastReceiver", Toast.LENGTH_SHORT).show();//表示将这条广播截断，后面的广播接收器将无法再接收这条广播abortBroadcast();}}</span><span style="font-size:18px;"></span>

2.这里仍然是在广播接收器的onReceive()方法中弹出了一段文本信息。然后在AndroidManifest.xml中对这个广播接收器进行注册。

<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.king.broadcasttest2"    android:versionCode="1"    android:versionName="1.0" >     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="14" />    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >                <!-- </span><pre name="code" class="html"><span style="font-size:14px;"><strong>android:priority="100":有序广播的优先级</strong></span>

--> <receiver android:name=".AnotherBroadcastReceiver"> <intent-filter android:priority="100"> <action android:name="com.king.broadcasttest.MY_BROADCAST"/> </intent-filter> </receiver> <activity android:name="com.king.broadcasttest2.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application></manifest>

3.MainActivity.java

<span style="font-size:14px;">package com.king.broadcasttest2;import android.os.Bundle;import android.app.Activity;import android.content.Intent;import android.view.Menu;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);Button button = (Button) findViewById(R.id.button);button.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View arg0) {Intent intent = new Intent("com.king.broadcasttest.MY_BROADCAST");sendBroadcast(intent);</span>

<span style="font-size:14px;"><span style="white-space:pre"></span>//发送有序广播</span><pre name="code" class="java"><span style="font-size:14px;">//</span><span style="font-family: Arial, Helvetica, sans-serif;">sendOrderedBroadcast(intent, null);</span>

}});}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}}

4.可以看到，AnotherBroadcastReceiver同样接收的是com.king.broadcasttest.MY_BROADCAST这条广播。现在运行BroadcastTest2项目将这个程序安装到模拟器上，然后重新回到BroadcastTest项目的主界面，并点击一下SendBroadcast按钮，就会分别弹出两次提示信息。

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