android 51 有序廣播

標籤：

無序廣播：一條廣播發送出去，多個接收者接收沒有順序。
有序廣播：廣播接收者可以設定優先權，優先順序高的先收到廣播。
有序廣播可以設定優先權。

mainActivity.java

package com.sxt.day07_06;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.util.Log;import android.view.Menu;public class MainActivity extends Activity {    ThirdReceiver mReceiver;        @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        registgerReceiver();        Intent intent=new Intent("com.sxt.day07_06.order_broadcast");        intent.putExtra("key", "hello java");        sendOrderedBroadcast(intent, null);//發送有序廣播    }    //註冊第三層級的廣播接收者，第一第二層級的廣播接收者在系統說明檔案中註冊，    private void registgerReceiver() {        mReceiver=new ThirdReceiver();        IntentFilter filter=new IntentFilter("com.sxt.day07_06.order_broadcast");//com.sxt.day07_06.order_broadcast廣播的字串        filter.setPriority(600);//設定優先權        registerReceiver(mReceiver, filter);    }    //java定義的第三層級的廣播接收這    class ThirdReceiver extends BroadcastReceiver{        public void onReceive(Context context, android.content.Intent intent) {            Log.i("main","ThirdReceiver.onReceive()");        };    }    @Override    protected void onDestroy() {        super.onDestroy();        unregisterReceiver(mReceiver);//銷毀的時候取消註冊的廣播接收者，釋放資源。    }}

第一個廣播接收者：

package com.sxt.day07_06;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;public class FirstReceiver extends BroadcastReceiver {    @Override    //優先順序第一的廣播接收者    public void onReceive(Context context, Intent intent) {        String value=intent.getStringExtra("key");//mainActivity的字串        Log.i("main","FirstReceiver.onReceive():"+value);        setResultData("來源於FirstReceiver的文本");//向第二層級的廣播接收者發送字串，    }}

第二個廣播接收者：

package com.sxt.day07_06;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;public class SecondReceiver extends BroadcastReceiver {    @Override    //優先順序第二的廣播接收者    public void onReceive(Context context, Intent intent) {        String value=intent.getStringExtra("key");//mainActivity的字串        String text=getResultData();//第一層級廣播接收者發過來的資料        Log.i("main","SecondReceiver.onReceive(),intent中攜帶的文本:"+value+","+text);        if(isOrderedBroadcast()){//如果收到的廣播是有序廣播            abortBroadcast();//終止廣播        }    }}

系統描述檔案：

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.sxt.day07_06"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="18" />    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >        <activity            android:name="com.sxt.day07_06.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>        <receiver android:name="com.sxt.day07_06.FirstReceiver">   註冊廣播接收者            <intent-filter android:priority="800">                <action android:name="com.sxt.day07_06.order_broadcast"/>            </intent-filter>        </receiver>        <receiver android:name="com.sxt.day07_06.SecondReceiver">            <intent-filter android:priority="700">                <action android:name="com.sxt.day07_06.order_broadcast"/>            </intent-filter>        </receiver>    </application></manifest>

 

android 51 有序廣播