Android's Broadcastreceiver

Broadcastreceiver is also one of the four components of Android.

First of all, I have a little understanding of Broadcastreceiver: Broadcastreceiver is mainly used to collect messages, including the system is not enough battery tips or to receive text messages when the thing to do.

More official understanding: In Android, broadcast is a widely used mechanism for transferring information between applications. Broadcastreceiver is a class of components that are filtered to receive and respond to the sent broadcast.

Write some examples.

A small example of the broadcast of a receiving system.

An example is a hint about a broken network.

1. Write a class yourself, inherit Broadcastreceiver

Package Zf.receiver;import Android.content.broadcastreceiver;import Android.content.context;import Android.content.intent;import Android.net.connectivitymanager;import Android.net.networkinfo;import Android.widget.toast;public class Myreceiver extends Broadcastreceiver {@Overridepublic void OnReceive (Context context , Intent Intent) {//TODO auto-generated method Stubif (!isnetworkavailable (context)) {Toast.maketext (context, "Pro, off the net!) ", Toast.length_short). Show ();}} Determines whether the public static Boolean isnetworkavailable (context context) is disconnected, {connectivitymanager mgr = (connectivitymana          GER) Context.getsystemservice (Context.connectivity_service);          Networkinfo[] info = Mgr.getallnetworkinfo (); if (info = null) {for (int i = 0; i < info.length; i++) {if (info[i].getstate () = = = Net                  WorkInfo.State.CONNECTED) {return true;      }}} return false; } }

2. Register in the Androidmanifext.xml file

<receiver    android:name= "Zf.receiver.MyReceiver" >    <intent-filter>        <action android: Name= "Android.net.conn.CONNECTIVITY_CHANGE"/>        <category android:name= "Android.intent.category.DEFAULT "/>    </intent-filter></receiver>

Allow networked operations at the same time

<uses-permission android:name= "Android.permission.ACCESS_NETWORK_STATE"/>

This allows the network to be disconnected when it is run.

Register yourself with a broadcast and then broadcastreceiver receive a small example.

1. In the activity

public void OnCreate (Bundle savedinstancestate) {        super.oncreate (savedinstancestate);        Setcontentview (r.layout.main);                BTN = (Button) Findviewbyid (r.id.button01);        Btn.setonclicklistener (New Onclicklistener () {@Overridepublic void OnClick (View v) {Intent intent= new Intent (); Intent.setaction (my_action);//Add additional information Intent.putextra for intent ("MSG", "Day, I Grass");//Issue Broadcast sendbroadcast (intent);});    }

2. Registering in the Androidmanifext.xml file

<receiver              android:name= "myreceive" >              <intent-filter>                 <action android:name= " Com.chaowen.action.MY_ACTION "/>              </intent-filter>           </receiver>

3. Create a class to inherit Broadcastreceiver and implement its onreceiver

Package Com.chaowen;import Android.content.broadcastreceiver;import Android.content.context;import Android.content.intent;import android.widget.toast;/** * Receive broadcast * @author Chaowen * */public class Myreceive extends BROADCA streceiver {@Overridepublic void OnReceive (context context, Intent Intent) {     //Get information from Intent string msg = Intent.getstringextra ("msg");        Use Toast to display Toast.maketext (context, MSG, Toast.length_long). Show ();}}

That's all.

There should be more places to add.

Android's Broadcastreceiver