Android broadcast explorer Programming

In Android, broadcast is a very useful function. Broadcast can notify other broadcasts to accept this event. Such as insufficient power supply and poor signal.

Below I made a simple demo, first look at the activity

 
 

  
  
package com.android.broadcasttest; 
  
  
 
  
  
import android.app.Activity; 
  
  
import android.content.Intent; 
  
  
import android.os.Bundle; 
  
  
import android.view.View; 
  
  
import android.view.View.OnClickListener; 
  
  
import android.widget.Button; 
  
  
 
  
  
public class BroadcastTest extends Activity { 
  
  
    public static final String NEW_LIFEFORM_DETECTED =  
  
  
        "com.android.broadcasttest.NEW_LIFEFORM"; 
  
  
     
  
  
    /** Called when the activity is first created. */ 
  
  
    @Override 
  
  
    public void onCreate(Bundle savedInstanceState) { 
  
  
        super.onCreate(savedInstanceState); 
  
  
        setContentView(R.layout.main); 
  
  
         
  
  
        Button btn0 = (Button)findViewById(R.id.btn0); 
  
  
        btn0.setOnClickListener(new OnClickListener() { 
  
  
            public void onClick(View v) { 
  
  
                Intent it = new Intent(NEW_LIFEFORM_DETECTED);           
  
  
                sendBroadcast(it); 
  
  
            } 
  
  
        }); 
  
  
    } 
  
  
} 
 
 

A button is generated in this activity. When the button is pressed, a broadcast is sent through sendbroadcast.

Let's look at the broadcast receiver code:

 
 

  
  
Package com. Android. broadcasttest;
  
  
 
  
  
Import Android. content. broadcastreceiver;
  
  
Import Android. content. context;
  
  
Import Android. content. intent;
  
  
Import Android. util. log;
  
  
Import Android. widget. Toast;
  
  
 
  
  
Public class mybroadcastreceiver extends broadcastreceiver {
  
  
Public static final string burn =
  
  
"Com. paad. Alien. Action. burn_it_with_fire ";
  
  

  
  
Public mybroadcastreceiver (){
  
  
Log. V ("broadcast_tag", "mybroadcast ");
  
  
}
  
  
@ Override
  
  
Public void onreceive (context, intent ){
  
  
// Todo auto-generated method stub
  
  
Toast. maketext (context, "successfully received broadcast:", Toast. length_long). Show ();
  
  
}
  
  
 
  
  
}
 
 

In onreceive (), an action is performed when the broadcast is received.

We also need to register the handler in androidmanifest. xml

 
 

  
  
<?xml version="1.0" encoding="utf-8"?> 
  
  
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
  
  
      package="com.android.broadcasttest" 
  
  
      android:versionCode="1" 
  
  
      android:versionName="1.0"> 
  
  
    <application android:icon="@drawable/icon" android:label="@string/app_name"> 
  
  
        <activity android:name=".BroadcastTest" 
  
  
                  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=".MyBroadcastReceiver"> 
  
  
            <intent-filter> 
  
  
                <action android:name="com.android.broadcasttest.NEW_LIFEFORM" /> 
  
  
            </intent-filter> 
  
  
        </receiver> 
  
  
    </application>         
  
  
    <uses-sdk android:minSdkVersion="8" /> 
  
  
</manifest>  
 
 

The operator's Action defines the broadcast that the receiver can accept.