Broadcast receivers allow apps to register for system-wide events like low battery or new SMS messages. A broadcast receiver subclass handles these events by overriding the onReceive() method. To receive broadcasts, the receiver must be declared in the manifest and permissions may need to be set depending on the event. Common examples of broadcasts are for battery level changes, storage changes, Bluetooth connections, and SMS messages received.

1. Broadcast Receiver
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Broadcasts are system wide events
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Examples
– SMS received , battery low, bluetooth,
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Broadcast-Receiver
–
Handles these events

2. Broadcast Receiver
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Cannot display User Inferace
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Must be handled within 10 seconds
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Can start a service for background processing

3. Broadcast Receiver subclass
class ........ extends BroadcastReceiver
{
onReceive( )
{
your code to handle the broadcast event
}
}

4. Steps
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create subclass of BroadcastReceiver
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onReceive()
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Get the intent – check if it has SMS info
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Register our receiver in manifest
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Set the SMS permissions in manifest

5. Steps
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create subclass of BroadcastReceiver
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onReceive()
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Register our receiver in manifest
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Set the SMS permissions in manifest
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Get the intent – check if it has SMS info

6. onReceive
String action="android.provider.Telephony.SMS_RECEIVED";
public void onReceive(Context c, Intent i) {
final Bundle bundle = i.getExtras();
if(i.getAction().equals(action))
{
Toast.makeText(c, "SMS Received", Toast.LENGTH_SHORT).show();
String msg= parseSMS(bundle);
Toast.makeText(c, msg, Toast.LENGTH_SHORT).show();
}
}

7. Extract SMS
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Intent
Bundle
PDU
SMS

8. Extract SMS
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Intent
Bundle
PDU
Bundle bundle = intent.getExtras();
Object[] pdusObj = bundle.get("pdus");
SmsMessage msg =
SmsMessage.createFromPdu((byte[])
pdusObj[0]);
SMS

9. Extract SMS
●
Intent
Bundle
PDU
SMS

10. Examples of broadcasts
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Examples for system events Event Usage
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Intent.ACTION_BATTERY_LOW
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Intent.ACTION_BATTERY_OKAY The battery level has risen again
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Intent.ACTION_BOOT_COMPLETED
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Intent.ACTION_DEVICE_STORAGE_LOW Storage space on the device is getting limited
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Intent.ACTION_DEVICE_STORAGE_OK The storage situation has improved again
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Intent.ACTION_HEADSET_PLUG A headset was plugged in or a previously plugged headset was removed
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Intent.ACTION_LOCALE_CHANGED
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Intent.ACTION_MY_PACKAGE_REPLACED
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Intent.ACTION_PACKAGE_ADDED A new app has been installed
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Intent.ACTION_POWER_CONNECTED
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Intent.ACTION_POWER_DISCONNECTED The device has been disconnected again
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KeyChain.ACTION_STORAGE_CHANGED The keystore changed
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BluetoothDevice.ACTION_ACL_CONNECTED A Bluetooth ACL connection has been established
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The battery level has fallen below a threshold
Android is up and running
The user changed the language of the device
Your app has been updated
The device has been plugged in
AudioManager.ACTION_AUDIO_BECOMING_NOISY The internal audio speaker is about to be used instead
of other output means (like a headset)