BroadcastReceiver

最新推荐文章于 2025-06-26 15:48:25 发布

iteye_13411

最新推荐文章于 2025-06-26 15:48:25 发布

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BroadcastReceiver
java.lang.Object
android.content.BroadcastReceiver
BaseclassforcodethatwillreceiveintentssentbysendBroadcast().
YoucaneitherdynamicallyregisteraninstanceofthisclasswithContext.registerReceiver()
orstaticallypublishanimplementationthroughthe<receiver>taginyourAndroidManifest.xml.
Note:IfregisteringareceiverinyourActivity.onResume()implementation,youshouldunregisteritinActivity.onPause().
(Youwon'treceiveintentswhenpaused,andthiswillcutdownonunnecessarysystemoverhead).
DonotunregisterinActivity.onSaveInstanceState(),becausethiswon'tbecallediftheusermovesbackinthehistorystack.
该类主要用来接收sendBroadcast()发出的intent。
可以通过在代码中用Context.registerReceiver()的形式动态注册BroadcastReceiver。
也可以在AndroidManifest.xml中通过<receiver>来注册BroadcastReceiver。

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`.

BroadcastReceiver主要有两大类：
Normalbroadcasts（普通广播）：It(sentwithContext.sendBroadcast)arecompletelyasynchronous.
Allreceiversofthebroadcastareruninanundefinedorder,oftenatthesametime.
Thisismoreefficient,butmeansthatreceiverscannotusetheresultorabortAPIsincludedhere.
该广播通过 Context.sendBroadcast 这种发送发送。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receivers接收器无法使用theresultorabortAPIs
Orderedbroadcasts（有序广播）：It(sentwithContext.sendOrderedBroadcast)aredeliveredtoonereceiveratatime.
Aseachreceiverexecutesinturn,itcanpropagatearesulttothenextreceiver,
oritcancompletelyabortthebroadcastsothatitwon'tbepassedtootherreceivers.
Theorderreceiversrunincanbecontrolledwiththe android:priorityattribute
ofthematchingintent-filter;
receiverswiththesameprioritywillberuninanarbitraryorder.
该广播是通过 Context.sendOrderedBroadcast 来发送。所有的receiver依次执行。
receiver接收器可以把结果传给下一个receiver接收器。
receiver接收器也可从丢掉广播，使该广播不在传送给别的接收器。
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。
注意1：虽然发送广播和Context.startActivity()都使用了Intent。但是他们的机制是完全不一样的。
注意2：只有Orderedbroadcasts（有序广播）才能把结果传给下一个receiver接收器。
才能使用abortBroadcast()丢掉广播
BroadcastReceiver的生命周期：
BroadcastReceiver的生命周期非常短暂的,而且是消息一到达则创建执行完毕就立刻销毁的.
当函数onReceive(Context,Intent)返回后系统就认为该对象已经被完成，不会在使用它了，系统立刻销毁该对象。
因此它的生命周期很短，不易做太多的事情，也不要做任何异步操作。
对于耗时的事情通常放在Service来处理，在BroadcastReceiver调用Context.startService()启动一个服务来处理耗时的工作。 注意1：BroadcastReceiver是在intent匹配后再实例化，而且每次都是重新实例化的。 注意2：因为onReceive是运行在themainthreadofitsprocess，所有如果该函数的运行时间超过了10秒， 系统就会认为该程序没响应，会弹出杀死该程序的选择框。 注意3：程序中手动注册的BroadcastReceiver，并不会重新实例化的。具体见实例1 Permissions 如果在发送广播的时候权限项非null,那么接收接收广播的应用程序必须要有相对应的权限。 可以自定义Permissions，但是Permissions首先要在AndroidManifest.xml中进行申明 示例1： Intentintent=newIntent("com.teleca.action.HELLO"); sendBroadcast(intent); AndroidManifest.xml文件 <receiverandroid:name="MyReceiver"> <intent-filter> <actionandroid:name="com.teleca.action.HELLO"/> </intent-filter> </receiver> BroadcastReceiver代码 publicclassMyReceiverextendsBroadcastReceiver{ finalstaticStringACTION_HELLO="com.teleca.action.HELLO"; finalstaticStringtag="hubin"; publicvoidonReceive(Contextcontext,Intentintent) { if(intent.getAction().equals(ACTION_HELLO)) { Log.i(tag,"hello,robin"); } } } 示例2： Stringaction="com.teleca.action.HELLO"; Stringpermission="com.teleca.permission.ACCESS"; Intentintent=newIntent(action); sendBroadcast(intent,permission); BroadcastReceiver代码和例1相同. AndroidManifest.xml文件 <?xmlversion="1.0"encoding="utf-8"?> <manifestxmlns:android="http://schemas.android.com/apk/res/android" package="com.teleca" android:versionCode="1" android:versionName="1.0"> <permissionandroid:name="com.teleca.permission.ACCESS" android:label="@string/MyPermission" android:description="@string/MyPermission" android:protectionLevel="dangerous"/>  <applicationandroid:icon="@drawable/icon"android:label="@string/app_name"> <activityandroid:name=".Hello" android:label="@string/app_name"> <intent-filter> <actionandroid:name="android.intent.action.MAIN"/> <categoryandroid:name="android.intent.category.LAUNCHER"/> </intent-filter> </activity> <activityandroid:name=".Hello2" android:label="@string/app_name"> <intent-filter> <actionandroid:name="com.teleca.action.MAIN"/> <categoryandroid:name="com.teleca.category.DEFAULT"/> <categoryandroid:name="android.intent.category.DEFAULT"/> <dataandroid:mimeType="vnd.android.cursor.item/vnd.google.note"android:scheme="weather"android:host="com.msi.manning"/> </intent-filter> </activity> <receiverandroid:name="MyReceiver"> <intent-filter> <actionandroid:name="com.teleca.action.HELLO"/> </intent-filter> </receiver> </application> <uses-sdkandroid:minSdkVersion="7"/> <uses-permissionandroid:name="com.teleca.permission.ACCESS"></uses-permission>  </manifest> 实例1： packagecom.teleca; importandroid.app.Activity; importandroid.content.BroadcastReceiver; importandroid.content.Context; importandroid.content.Intent; importandroid.content.IntentFilter; importandroid.os.Bundle; importandroid.util.Log; importandroid.view.View; importandroid.view.View.OnClickListener; importandroid.widget.Button; importandroid.widget.LinearLayout; publicclassHelloextendsActivity{ Stringtag="hubin"; /**Calledwhentheactivityisfirstcreated.*/ @Override publicvoidonCreate(BundlesavedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.main); Buttonbutton=(Button)findViewById(R.id.Button01); OnClickListenerlistener=newOnClickListener(){ publicvoidonClick(Viewv){ Intentintent=newIntent(Hello.this,Hello2.class); startActivity(intent); finish();//@2 } }; IntentFilterfilter=newIntentFilter(); filter.addAction("Hello"); this.registerReceiver(receiver,filter); Log.i(tag,"createone1"); ; } protectedvoidonDestroy() { super.onDestroy(); Log.i(tag,"oneDestroy"); } publicBroadcastReceiverreceiver=newBroadcastReceiver(){ publicvoidonReceive(Contextcontext,Intentintent){ Log.i(tag,"receiver:"+this);//@1 } }; } 文件2：Hello2.java importandroid.view.View; importandroid.view.View.OnClickListener; importandroid.widget.Button; publicclassHello2extendsActivity{ Stringtag="hubin"; /**Calledwhentheactivityisfirstcreated.*/ @Override publicvoidonCreate(BundlesavedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.main2); Buttonbutton=(Button)findViewById(R.id.Button01); OnClickListenerlistener=newOnClickListener(){ publicvoidonClick(Viewv){ Intentintent=newIntent("Hello"); sendBroadcast(intent); } }; button.setOnClickListener(listener); } } 注意1:程序中手动注册的BroadcastReceiver，并不会重新实例化的。这点和AndroidManifest.xml不一样 注意2:它的存活时间是要一直到Activity死亡。如果调用了finish(),该Activity就死亡，receiver也同时死亡掉。