Learn About Broadcast Reciever in Android

Introduction

This article explains the Broadcast Receiver in Android.

A Broadcast Receiver is a receiver that helps to catch Android operating system specific events. A Broadcast Receiver is an Android component that listens for device orientation changes like SMS message received, phone call received, battery status received and WiFi comes on.

A Broadcast Receiver is used when a call is received. We then save the call details in our SQLite database. When the phone changes its state after receiving a call then the receiver notices the state change and saves the call into the SQLite database.

How to create a Broadcast Receiver

There are two ways to register and create a Broadcast Receiver. The first way is by the Android Manifest.xml file.

<receiver
android:name="BatteryChanged">
<intent-filter >
<action android:name="android.intent.action.BATTERY_CHANGED"/>
</intent-filter>
</receiver>

In Java file

On firing of the action android:name="android.intent.action.BATTERY_CHANGED" the onRecieve method will automatically call:

public class BatteryCheck extends BroadcastReceiver
{
public void onRecieve(Context context,Intent intent)
{
//Battery status will be received
}
}

Second way is to register dynamically

private BroadcastReceiver reciever=new BatteryChange();
private IntentFilter filter=new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
this.registerReciever(receiver,filter);
public class BatteryChange extends BroadcastReceiver
{
public void onReceive(Context context,Intent intent)
{
}
}

How to create a custom event and BroadcastReciever

Register a BroadcastReciever in the Android menifest.xml file like this:

<receiver
android:name="Reciever">
<intent-filter>
<action android:name="ax.example.mybroadcast"/>
</intent-filter>
</receiver>

Create a Java file and write this:

class Reciever extends BroadcastReceiver
{
public void onRecieve(Context context,Intent intent)
{
}
}

Send Broadcast event

Send a broadcast event using the following:

Intent intent = new Intent();
intent.setAction("ax.example.myBroadcast");
sendBroadCast(intent);

Another way to define a receiver

public class RecieverExample extends Activity
{
private BroadcastReceiver receiver = new BroadcastReceiver()
{
@Override
public void onReceive(Context context, Intent intent) {}
};
private IntentFilter filter = new IntentFilter(Intent.ACTION_CONFIGURATION_CHANGED);
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
protected void onResume()
{
this.registerReceiver(receiver, filter);
super.onResume();
}
@Override
protected void onPause()
{
this.unregisterReceiver(receiver);
super.onPause();
}
}

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