发送有序广播

来源：互联网发布：手机数据永久删除编辑：程序博客网时间：2024/06/18 15:04

一：运行效果图
这里写图片描述
二：1：创建一个名为：“拦截有序广播”的应用程序，布局文件activity_main.xml如下所示：

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"   android:background="@drawable/stitch_one"    tools:context=".MainActivity">    <Button        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_centerHorizontal="true"        android:layout_marginTop="80dp"        android:onClick="send"        android:text="发送有序广播"        android:paddingLeft="5dp"        android:paddingRight="5dp"        android:background="#FBFBFF"        android:textSize="20sp"    /></RelativeLayout>

上述布局文件中定义了一个Button按钮，并为按钮注册了一个点击事件send，当用户点击该按钮时，会发送一条有序广播。
2：MainActivity代码如下：

package cn.edu.bzu.orderbroadcast;import android.content.Intent;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);    }    public void send (View view){        Intent intent=new Intent();        intent.setAction("Intercept_Stitch");        sendOrderedBroadcast(intent,null);    }}

sendOrderedBroadcast(intent,null)用于发送一个有序广播，在该方法中接收两个参数，第1个参数是指定的意图，设置要发送的广播事件。第2个参数指定接收者的权限，如果不想让所有的接收者都看到，可以显式地指定接收者的权限，目前不关心权限可以将其指定为null.
3:添加三个广播接收者MyBroadcastReceiverOne,MyBroadcastReceiverTwo,MyBroadcastReceiverThre

package cn.edu.bzu.orderbroadcast;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;public class MyBroadcastReceiverOne extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        // TODO: This method is called when the BroadcastReceiver is receiving        // an Intent broadcast.        Log.i("MyBroadcastReceiverOne","自定义的广播接收者one,接收到了广播事件");    }}

package cn.edu.bzu.orderbroadcast;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;public class MyBroadcastReceiverTwo extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        // TODO: This method is called when the BroadcastReceiver is receiving        // an Intent broadcast.        Log.i("MyBroadcastReceiverTwo","自定义的广播接收者two,接收到了广播事件");        abortBroadcast();        Log.i("MyBroadcastReceiverTwo","我是广播接收者Two,广播被我终结了");    }}

package cn.edu.bzu.orderbroadcast;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;public class MyBroadcastReceiverThre extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        // TODO: This method is called when the BroadcastReceiver is receiving        // an Intent broadcast.        Log.i("MyBroadcastReceiverThre","自定义的广播接收者thre,接收到了广播事件");    }}

4：三个广播接收者创建成功后，需要在清单文件中注册并为它们指定不同的优先级，清单文件代码如下：

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="cn.edu.bzu.orderbroadcast">    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        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=".MyBroadcastReceiverOne">            <intent-filter android:priority="1000">                <action android:name="Intercept_Stitch" />            </intent-filter>        </receiver>        <receiver android:name=".MyBroadcastReceiverTwo">            <intent-filter android:priority="200">                <action android:name="Intercept_Stitch" />            </intent-filter>        </receiver>        <receiver android:name=".MyBroadcastReceiverThre">            <intent-filter android:priority="600">                <action android:name="Intercept_Stitch" />            </intent-filter>        </receiver>    </application></manifest>

三个广播接收者中MyBroadcastReceiverOne的优先级最高，其次是MyBroadcastReceiverThre,最低的是MyBroadcastReceiverTwo.
程序启动后，单机“发送有序广播”按钮，发送一条广播事件
这里写图片描述
优先级最高的MyBroadcastReceiverOne最先收到广播事件，其次是MyBroadcastReceiverThre,最后是MyBroadcastReceiverTwo,说明广播接收者的优先级决定了广播接收的先后顺序。
5：若将广播接收者MyBroadcastReceiverTwo优先级同样设置为1000，并将MyBroadcastReceiverTwo注册在MyBroadcastReceiverOne前面，再来运行程序

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="cn.edu.bzu.orderbroadcast">    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        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=".MyBroadcastReceiverTwo">            <intent-filter android:priority="1000">                <action android:name="Intercept_Stitch" />            </intent-filter>        </receiver>        <receiver android:name=".MyBroadcastReceiverOne">            <intent-filter android:priority="1000">                <action android:name="Intercept_Stitch" />            </intent-filter>        </receiver>        <receiver android:name=".MyBroadcastReceiverThre">            <intent-filter android:priority="600">                <action android:name="Intercept_Stitch" />            </intent-filter>        </receiver>    </application></manifest>

此时再来运行程序：
这里写图片描述
MyBroadcastReceiverTwo最先接收到了广播事件，其次是MyBroadcastReceiverOne,这说明当两个广播接收者优先级相同时，先注册的广播接收者会先接收到广播事件。
6：修改MyBroadcastReceiverTwo如下

package cn.edu.bzu.orderbroadcast;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;public class MyBroadcastReceiverTwo extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        // TODO: This method is called when the BroadcastReceiver is receiving        // an Intent broadcast.        Log.i("MyBroadcastReceiverTwo","自定义的广播接收者two,接收到了广播事件");        abortBroadcast();        Log.i("MyBroadcastReceiverTwo","我是广播接收者Two,广播被我终结了");    }}

运行程序：
这里写图片描述
只有MyBroadcastReceiverTwo接收到了自定义的广播事件，其他的广播接收者都没有接收到，因此说明广播被MyBroadcastReceiverTwo终止了。

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