BroadcastReceiver（有序广播篇）

BroadcastReceiver 所对应的广播分两类： 普通广播 和 有序广播 。

普通广播 通过 Context.sendBroadcast() 方法来发送。它是完全异步的。

所有的receivers接收器的执行顺序不确定。 因此，所有的receivers接收器接收broadcast的顺序不确定。

这种方式效率更高。但是 BroadcastReceiver 无法使用 setResult系列 ， getResult系列 及 abort系列API

有序广播 是通过 Context.sendOrderedBroadcast 来发送。所有的receiver依次执行。

BroadcastReceiver可以使用setResult系列函数来结果传给下一个BroadcastReceiver，通过getResult系列函数来取得上个BroadcastReceiver返回的结果，并可以abort系列函数来让系统丢弃该广播让，使用该广播不再传送到别的 BroadcastReceiver。

可以通过在 intent-filter 中设置 android:priority 属性来设置receiver的优先级。 优先级相同的receiver其执行顺序不确定。

如果 BroadcastReceiver 是代码中注册的话，且其 intent-filter 拥有 相同 android:priority 属性 的话，先注册的将先收到广播。

主要函数

Public Methods

<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#abortBroadcast()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">abortBroadcast</a></span>()</nobr> Sets the flag indicating that this receiver should abort the current broadcast; only works with broadcasts sent through Context.sendOrderedBroadcast.
<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#clearAbortBroadcast()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">clearAbortBroadcast</a></span>()</nobr> Clears the flag indicating that this receiver should abort the current broadcast.
<nobr style="line-height:21px">final boolean</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#getAbortBroadcast()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">getAbortBroadcast</a></span>()</nobr> Returns the flag indicating whether or not this receiver should abort the current broadcast.
<nobr style="line-height:21px">final boolean</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#getDebugUnregister()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">getDebugUnregister</a></span>()</nobr> Return the last value given to setDebugUnregister(boolean).
<nobr style="line-height:21px">final int</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#getResultCode()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">getResultCode</a></span>()</nobr> Retrieve the current result code, as set by the previous receiver.
<nobr style="line-height:21px">final<a rel="nofollow" href="http://developer.android.com/reference/java/lang/String.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">String</a></nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#getResultData()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">getResultData</a></span>()</nobr> Retrieve the current result data, as set by the previous receiver.
<nobr style="line-height:21px">final<a rel="nofollow" href="http://developer.android.com/reference/android/os/Bundle.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">Bundle</a></nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#getResultExtras(boolean)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">getResultExtras</a></span>(boolean makeMap)</nobr> Retrieve the current result extra data, as set by the previous receiver.
<nobr style="line-height:21px">final<a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.PendingResult.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">BroadcastReceiver.PendingResult</a></nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#goAsync()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">goAsync</a></span>()</nobr> This can be called by an application in onReceive(Context, Intent)to allow it to keep the broadcast active after returning from that function.
<nobr style="line-height:21px">final boolean</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#isInitialStickyBroadcast()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">isInitialStickyBroadcast</a></span>()</nobr> Returns true if the receiver is currently processing the initial value of a sticky broadcast -- that is, the value that was last broadcast and is currently held in the sticky cache, so this is not directly the result of a broadcast right now.
<nobr style="line-height:21px">final boolean</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#isOrderedBroadcast()" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">isOrderedBroadcast</a></span>()</nobr> Returns true if the receiver is currently processing an ordered broadcast.
<nobr style="line-height:21px">abstract void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#onReceive(android.content.Context,%20android.content.Intent)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">onReceive</a></span>(<a rel="nofollow" href="http://developer.android.com/reference/android/content/Context.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">Context</a>context,<a rel="nofollow" href="http://developer.android.com/reference/android/content/Intent.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">Intent</a>intent)</nobr> This method is called when the BroadcastReceiver is receiving an Intent broadcast.
<nobr style="line-height:21px"><a rel="nofollow" href="http://developer.android.com/reference/android/os/IBinder.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">IBinder</a></nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#peekService(android.content.Context,%20android.content.Intent)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">peekService</a></span>(<a rel="nofollow" href="http://developer.android.com/reference/android/content/Context.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">Context</a>myContext,<a rel="nofollow" href="http://developer.android.com/reference/android/content/Intent.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">Intent</a>service)</nobr> Provide a binder to an already-running service.
<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#setDebugUnregister(boolean)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">setDebugUnregister</a></span>(boolean debug)</nobr> Control inclusion of debugging help for mismatched calls to {@ Context#registerReceiver(BroadcastReceiver, IntentFilter) Context.registerReceiver()}.
<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#setOrderedHint(boolean)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">setOrderedHint</a></span>(boolean isOrdered)</nobr> For internal use, sets the hint about whether this BroadcastReceiver is running in ordered mode.
<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#setResult(int,%20java.lang.String,%20android.os.Bundle)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">setResult</a></span>(int code,<a rel="nofollow" href="http://developer.android.com/reference/java/lang/String.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">String</a>data,<a rel="nofollow" href="http://developer.android.com/reference/android/os/Bundle.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">Bundle</a>extras)</nobr> Change all of the result data returned from this broadcasts; only works with broadcasts sent through Context.sendOrderedBroadcast.
<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#setResultCode(int)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">setResultCode</a></span>(int code)</nobr> Change the current result code of this broadcast; only works with broadcasts sent through Context.sendOrderedBroadcast.
<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#setResultData(java.lang.String)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">setResultData</a></span>(<a rel="nofollow" href="http://developer.android.com/reference/java/lang/String.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">String</a>data)</nobr> Change the current result data of this broadcast; only works with broadcasts sent through Context.sendOrderedBroadcast.
<nobr style="line-height:21px">final void</nobr>	<nobr style="line-height:21px"><span style="line-height:21px; margin-right:2px"><a rel="nofollow" href="http://developer.android.com/reference/android/content/BroadcastReceiver.html#setResultExtras(android.os.Bundle)" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">setResultExtras</a></span>(<a rel="nofollow" href="http://developer.android.com/reference/android/os/Bundle.html" style="color:rgb(0,102,153); line-height:21px; text-decoration:none">Bundle</a>extras)</nobr> Change the current result extras of this broadcast; only works with broadcasts sent through Context.sendOrderedBroadcast.

以下是一个关于 有序广播 的实例。

实例1：

MainActivity.java文件

package com.teleca.robin.BroadcastReceiverExample;

import com.teleca.R;

import android.app.Activity;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.Intent;

import android.content.IntentFilter;

import android.os.Bundle;

import android.os.Handler;

import android.util.Log;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;

public class MainActivity extendsActivity {

TextView tv=null;

@Override

public void onCreate (Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main0);

tv=(TextView)findViewById(R.id.TextView1);

Button button = (Button) findViewById(R.id.Button1);

OnClickListener listener = new OnClickListener() {

public void onClick(View v) {

sendBroadcast();

}

};

button.setOnClickListener(listener);

}

protected void onResume()

{

super.onResume();

registerMyReceivers();

}

protected void onStop()

{

unRegisterMyReceivers();

super.onStop();

}

final static String ACTION_HELLO="com.teleca.robin.action.HELLO";

final static String KEY_ORDER_DETAIL="orderDetail";

void sendBroadcast()

{

Intent intent=new Intent(ACTION_HELLO);

String receiverPermission=null;

Handler scheduler=null;

int initialCode=0;

String initialData=null;

Bundle initialExtras=new Bundle();

sendOrderedBroadcast(intent, receiverPermission, resultReceiver, scheduler,

initialCode, initialData, initialExtras);

}

BroadcastReceiver receiverArray[]=new MyBroadcastReceiver[50];

void registerMyReceivers()

{

int k=receiverArray.length;

int priority=IntentFilter.SYSTEM_LOW_PRIORITY;

for (int i=0;i<k;i++)

{

receiverArray[i]=new MyBroadcastReceiver();

IntentFilter filter=new IntentFilter(ACTION_HELLO);

filter.setPriority(priority);

registerReceiver(receiverArray[i], filter);

if((i+1)%5==0)

priority++;

}

}

void unRegisterMyReceivers ()

{

int k=receiverArray.length;

for (int i=0;i<k;i++)

{

if(receiverArray[i]!=null)

{

unregisterReceiver(receiverArray[i]);

receiverArray[i]=null;

}

}

}

final static String tag="robin";

BroadcastReceiver resultReceiver=new BroadcastReceiver() {

@Override

public void onReceive(Context arg0, Intent intent) {

// TODO Auto-generated method stub

StringBuffer strBuffer=new StringBuffer();

int count= getResultCode();

strBuffer.append("there are "+count+" student\n");

strBuffer.append("the older are :"+ getResultData() +"\n");

strBuffer.append("the detail older are :"+ getResultExtras (true).getString(KEY_ORDER_DETAIL));

tv.setText(strBuffer.toString());

}

};

}

MyBroadcastReceiver.java文件

package com.teleca.robin.BroadcastReceiverExample;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.Intent;

import android.os.Bundle;

import android.util.Log;

class MyBroadcastReceiverextends BroadcastReceiver {

static int SN=0;

int id=SN++;

final static String tag="robin";

@Override

public void onReceive(Context arg0, Intent intent) {

// TODO Auto-generated method stub

if(intent.getAction().equals(MainActivity.ACTION_HELLO))

{

int count= getResultCode() +1;

setResultCode (count);

Log.i(tag,"this is student"+id);

String str= getResultData ();

if(str==null)

str=""+id;

else

str=str+" "+id;

setResultData (str);

Bundle b= getResultExtras(true) ;

str=b.getString(MainActivity.KEY_ORDER_DETAIL);

if(str==null)

str=""+id;

else

str=str+"->"+id;

b.putString(MainActivity.KEY_ORDER_DETAIL, str);

Log.i(tag,"str:"+str);

setResultExtras(b);

}

}

}

main0.xml文件

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:orientation="vertical"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:id="@+id/root"

>

<TextView

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:background="#FF0000FF"

android:minHeight="50dip"

android:text="@string/BroadcastReceiverExample"

android:id="@+id/TextView1"

/>

<Button android:text="@string/pressme"

android:id="@+id/Button1"

android:layout_width="wrap_content" android:layout_height="wrap_content"

></Button>

</LinearLayout>

AndroidManifest.xml中

<activity android:name="com.teleca.robin.BroadcastReceiverExample.MainActivity"

android:label="@string/app_name"

>

<intent-filter>

<action android:name="com.teleca.robin.Hello" />

<category android:name="android.intent.category.DEFAULT" />

</intent-filter>

</activity>