Develop Reference

Can't receive the broadcast when mentioned in manifest file

I'm trying to receive a broadcast when power source connects or disconnects to the device. So I mention the receiver in the manifest file but it doesn't work. But When I declare the broadcast dynamically it works fine.
public class PowerConnectionReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(context, "POWER CONNECTION CHANGED", Toast.LENGTH_LONG).show();
}
}
manifest code snippet
<receiver android:name=".PowerConnectionReceiver">
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_CONNECTED"/>
<action android:name="android.intent.action.ACTION_POWER_DISCONNECTED"/>
</intent-filter>
</receiver>

Implicit Broadcast Reciever isn't calling

I searched the web for alot of time and I don't understand why my custom broadcast
isn't working.
<receiver
android:name=".myservice.MyReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_CONNECTED" />
<action android:name="android.intent.action.ACTION_POWER_DISCONNECTED" />
<action android:name="android.intent.action.BATTERY_CHANGED"/>
<action android:name="android.intent.action.SCREEN_ON" />
<action android:name="android.intent.action.SCREEN_OFF" />
</intent-filter>
</receiver>
I don't it not recieve when I reconnet and disconnect the charger.
I did this for making thing simpale
public class MyReceiver extends BroadcastReceiver
{
#Override
public void onReceive(Context context, Intent intent)
{
Toast.makeText(context,"Battery", Toast.LENGTH_SHORT).show();
Log.i("Recive", "Yes");
}
}

From docs:
ACTION_BATTERY_CHANGED
Broadcast Action: This is a sticky broadcast containing the charging state, level, and other information about the battery. See BatteryManager for documentation on the contents of the Intent.
You cannot receive this through components declared in manifests, only by explicitly registering for it with Context.registerReceiver(). See ACTION_BATTERY_LOW, ACTION_BATTERY_OKAY, ACTION_POWER_CONNECTED, and ACTION_POWER_DISCONNECTED for distinct battery-related broadcasts that are sent and can be received through manifest receivers
So, you cannot use this BroadcastReceiver decalred in Manifest, only registering explicitly from your context.
Also, your power connection BroadcastReceiver seems correct. Try to separate it into another BroadcastReceiver, maybe action ACTION_BATTERY_CHANGED is interfering with other actions.
This is my declared BroadcastReceiver which I use and it's working in my app.
<receiver android:name=".PowerConnectionBroadcastReceiver">
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_CONNECTED"/>
<action android:name="android.intent.action.ACTION_POWER_DISCONNECTED"/>
</intent-filter>
</receiver>
PowerConnectionBroadcastReceiver
public class PowerConnectionBroadcastReceiver extends BroadcastReceiver {
private static final String TAG = "PowerRcvr";
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action.equals(Intent.ACTION_POWER_CONNECTED)) {
Log.d(TAG, "Device is charging");
} else if (action.equals(Intent.ACTION_POWER_DISCONNECTED)) {
Log.d(TAG, "Device is NOT charging");
} else {
Log.d(TAG, "Unable to check if device is charging or not");
}
}
}
NOTE: This code is working on Android 8 with targetSdkVersion 25 or lower.
In targetSdkVersion 26 or higher most of BroadcastReceivers doesn't work through Manifest due to background limitations. Here are documentation (thanks to Pawel) about that. So your IntentFilters wont work. To keep it working you can download your targetSdkVersion to 25 or lower.

Broadcast not triggered when process is created

I have a broadcast which monitors for unlock event for the phone. But when the app's process is killed and no longer in memory, Unlocking the phone does not trigger the Receiver, instead I can see in the Android studio, that new process is created for that app.
If lock and unlock it again, then as the process is already running, I can see the BroadcastReceiver is triggered.
<receiver
android:name=".UserPresentBroadcastReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.USER_PRESENT" />
</intent-filter>
</receiver>
Broadcast Receiver:
public class UserPresentBroadcastReceiver extends BroadcastReceiver {
private static final String TAG = UserPresentBroadcastReceiver.class.getSimpleName();
#Override
public void onReceive(Context arg0, Intent intent) {
Log.d(TAG, "onReceive: Unlock Boradcast received");
if (intent.getAction().equals(Intent.ACTION_USER_PRESENT)) {
Toast.makeText(arg0, "You just unlocked the device", Toast.LENGTH_LONG).show();
}
}
}
I am unable to understand this behavior. Is this the default behavior?

You have to register and unregister this broadcast receiver in Activity(or Service for listening in background all the time).
Manifest entry won't work.

Delay in Android connectivity change broadcast

I am listening for "android.net.conn.CONNECTIVITY_CHANGE" in my app with a broadcast receiver. It does work, but the only problem I have is that there is a huge delay in receiving this broadcast. It takes between 1-2 seconds for the app to receive this broadcast. Am I doing something wrong?
My Manifest entry -
<receiver android:name=".ConnectivityBroadcastReceiver"
android:exported="true">
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>
</intent-filter>
</receiver>
and ConnectivityBroadcastReceiver class -
public class ConnectivityBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Log.e(TAG,"Broadcast received");
final String action = intent.getAction();
if (action.equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
ConnectivityUtil.checkConnectivity(context);
}
}
}

How to instantiate activity based on received sms?

How would I have an activity or animation start when the users device receives an sms? I want to start/play an animation when a sms comes in while they are viewing my app. How would I go about doing that?

public class SmsReceiver extends BroadcastReceiver {
private static final String SMS_RECEIVED = "android.provider.Telephony.SMS_RECEIVED";
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(SMS_RECEIVED)) {
// here start the activity for animation or whatever you want to do
}
}
}
add this permission to your manifest
<uses-permission android:name="android.permission.RECEIVE_SMS"/>
add the receiver under your application tag in your manifest
<receiver android:name=".SmsReceiver" >
<intent-filter android:priority="999">
<action android:name="android.provider.Telephony.SMS_RECEIVED" >
</action>
</intent-filter>
</receiver>

Create a BroadcastReceiver for SMS
http://developer.android.com/reference/android/content/BroadcastReceiver.html
and act accordingly
SO Example if you had used search:
Android - SMS Broadcast receiver