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Not able to trigger the broadcast

I was learning concept of broadcast receivers and I wanted to make a project with which I can demonstrate triggering specific implicit receiver class which is kind of explicit broadcast.
I made 2 apps the sender app and receiver app for demonstration :
BROADCAST SENDER's MAIN ACTIVITY :
public class MainActivity extends AppCompatActivity {
//Declaring our views
TextView senderTextView;
Button sendButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//initializing views
senderTextView = findViewById(R.id.senderTextView);
sendButton = findViewById(R.id.sendButton);
//Setting onClick Listener on sendButton
sendButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//Calling Broadcast Method
Broadcast();
}
});
}
//Broadcast Method
private void Broadcast(){
//Creating private broadcast intent
Intent intent = new Intent("com.example.broadcastreceiver.PRIVATE_BROADCAST");
//Here we are going to find all the apps in our mobile that have registered for this broadcast in their manifests
//This will help us to find packages or apps registered for com.example.PRIVATE_BROADCAST action
PackageManager packageManager = getPackageManager();
//queryBroadcastReceivers of package manager will query all the receivers having intent filter for "com.example.PRIVATE_BROADCAST" action
//and store receivers info in resolveInfoList
List<ResolveInfo> resolveInfoList = packageManager.queryBroadcastReceivers(intent,0);
//Now we will iterate over this list to find our specific receiver and trigger it
//for each info in resolveInfoList
for (ResolveInfo info : resolveInfoList){
//if info's receiver class name is com.example.broadcastreceiver.CustomBroadcastReceiver (which is our receiver class in receiver app)
if(info.activityInfo.name.equals("com.example.broadcastreceiver.CustomBroadcastReceiver")){
//then use this info to get package name and receiver class name to make a componentName
ComponentName componentName = new ComponentName(info.activityInfo.packageName,info.activityInfo.name);
//now set this componentName to our intent
intent.setComponent(componentName);
}
}
//Sending our private broadcast to our android mobile
sendBroadcast(intent);
//setting textView
senderTextView.setText("Broadcast Sent!");
}
BROADCAST RECEIVER'S MANIFEST :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.example.broadcastreceiver">
<application
android:allowBackup="true"
android:dataExtractionRules="#xml/data_extraction_rules"
android:fullBackupContent="#xml/backup_rules"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.BroadcastReceiver"
tools:targetApi="31">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver
android:name=".CustomBroadcastReceiver"
android:exported="true">
<intent-filter>
<action android:name="com.example.broadcastreceiver.PRIVATE_BROADCAST"/>
</intent-filter>
</receiver>
</application>
</manifest>
BROADCAST RECEIVER's CustomBroadcastReceiver Class :
public class CustomBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
//Making a toast when broadcast is received
Toast.makeText(context, "Broadcast Receiver App : Custom Broadcast Receiver Triggered" , Toast.LENGTH_SHORT).show();
}
BroadcastReceiver's Mainactivity has nothing.
This should trigger the toast in CustomBroadcastReciever class of Broadcast Receiver App but due to some reason toast is not appearing please help.
Thanks in advance :)

Just created a demo app that works:
In app1, send the broadcast like this (obviously change package names):
public void sendBroadcast() {
Intent broadcastIntent = new Intent("com.example.testimplicitbroadcastreceiver.PRIVATE_BROADCAST");
broadcastIntent.setComponent(new ComponentName("com.example.testimplicitbroadcastreceiver",
"com.example.testimplicitbroadcastreceiver.CustomBroadcastReceiver"));
sendBroadcast(broadcastIntent);
}
In app2's manifest, register the BroadcastReceiver:
<receiver
android:name=".CustomBroadcastReceiver"
android:exported="true">
<intent-filter>
<action android:name="com.example.testimplicitbroadcastreceiver.PRIVATE_BROADCAST"/>
</intent-filter>
</receiver>
Voila, now app2 will receive your Broadcast in the CustomBroadcastReceiver.

Android keep app running in the background forever

I am still new to Android development, but I’m creating an app that sendings an HTTP request when it receives a broadcast (from a barcode scan). I have tried to implement some other solutions that I read on here but haven't quite figured it out yet. It would be great if someone could help me get going in the right direction.
Essentially, the end goal is for the app to keep running in the background forever so that even if the app is not open and a barcode is scanned and sent to the app via broadcast signal, the HTTP request is still sent.
This is what I have so far:
MainActivity.java
public class MainActivity extends Activity implements CompoundButton.OnCheckedChangeListener {
public static final String BARCODE_BROADCAST = "...";
private final BarcodeReceiver barcodeReceiver = new BarcodeReceiver();
private TextView mTextView;
private String scannedBarcode;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextView = (TextView) findViewById(R.id.barcode);
}
#Override
public void onResume() {
super.onResume();
registerBarcodeScanner();
}
#Override
public void onPause() {
super.onPause();
unregisterBarcodeScanner();
// this code needs to keep the app running
Intent restartService = new Intent("RestartService");
this.startService(restartService);
sendBroadcast(restartService);
}
public void onDestroy() {
super.onDestroy();
// this code needs to keep the app running
Intent restartService = new Intent("RestartService");
this.startService(restartService);
sendBroadcast(restartService);
}
private void registerBarcodeScanner() {
registerReceiver(barcodeReceiver, new IntentFilter(BARCODE_BROADCAST));
}
private void unregisterBarcodeScanner() {
unregisterReceiver(barcodeReceiver);
}
private void displayBarcode() {
if (scannedBarcode == null) return;
String text = getString(R.string.barcode_scanned, scannedBarcode);
mTextView.setText(text);
/* SEND HTTP REQUEST */
}
private class BarcodeReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action.equals(BARCODE_BROADCAST)) {
String barcode = intent.getStringExtra("Barcode");
if (barcode != null) {
scannedBarcode = barcode;
displayBarcode();
}
}
}
}
}
RestartService.java
public class RestartService extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
context.startService(new Intent(context, MainActivity.class));
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="..."
android:versionCode="1">
<uses-sdk android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
tools:replace="android:label">
<activity
android:name="...MainActivity"
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="...RestartService"
android:enabled="true"
android:exported="true"
android:label="RestartServiceWhenStopped"
android:permission="android.permission.RECEIVE_BOOT_COMPLETED">
<intent-filter>
<action android:name="RestartService" />
</intent-filter>
</receiver>
</application>
</manifest>

Broadcast receiver not working when app is closed

So I have two different apps made, one sends a broadcast and another receives it and displays a toast. However, when I close the receiver app the broadcast is no longer received by the second app even though I defined the receiver in the manifest file.
The broadcast sender in the MainActivity of app1.
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button b = (Button)findViewById(R.id.button2);
b.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent();
i.setAction("com.example.ali.rrr");
i.addFlags(Intent.FLAG_INCLUDE_STOPPED_PACKAGES);
sendBroadcast(i);
Log.e("Broadcast","sent");
}
});
}
App 2 broadcast receiver:
public class MyReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// TODO: This method is called when the BroadcastReceiver is receiving
// an Intent broadcast.
Toast.makeText(context, "Broadcast has been recieved!", Toast.LENGTH_SHORT).show();
Log.e("SUCCESS", "IN RECIEVER");
//throw new UnsupportedOperationException("Not yet implemented");
}
App 2s Manifest:
<?xml version="1.0" encoding="utf-8"?>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<receiver
android:name=".MyReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="com.example.ali.rrr" />
</intent-filter>
</receiver>
<activity
android:name=".MainActivity"
android:label="#string/title_activity_main"
android:theme="#style/AppTheme.NoActionBar" />
<activity
android:name=".Main2Activity"
android:label="#string/title_activity_main2"
android:theme="#style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

After registering my BroadcastReceiver (BR) statically in the manifest, applying the proper intent filters, using JobIntentService (and registering it in the manifest) to handle the work that was called from my BR, I was still getting inconsistent results.
Once all of what I listed above has been done you should be able to send an ADB command to activate your broadcast and process the work in your service even if the app is closed. This was working for me some of the time, but not all of the time.
This article describes limitation to BRs.
"As of Android 3.1 the Android system excludes all receiver from receiving intents by default if the corresponding application has never been started by the user or if the user explicitly stopped the application via the Android menu" (AKA a user executes Force Stop)
When I start the app by debugging it, then swipe it closed on my device, my ADB command never activates my BR. However, after my debugging session is over, when I open up the app on my device and swipe it closed, I can activate my BR through ADB commands.
This occurs because when you debug an application, then manually swipe it closed on the device, Android considers this a Force Stop hence why my BR cannot be activated until I re-open the app on the device without debugging.
Scoured the internet for hours, and wasn't able to find my solution, so I thought I'd post it here just in case some poor unfortunate soul is encountering the same weird functionality I was.
Happy coding :)

First of all you need to use the Service for this functionality to work.
In the Activity you can start and stop the service by using the below codes.
// to start a service
Intent service = new Intent(context, MyBrodcastRecieverService.class);
context.startService(service);
// to Stop service
Intent service = new Intent(context, MyBrodcastRecieverService.class);
context.stopService(service);
Then you can use the below service
public class MyBrodcastRecieverService extends Service
{
private static BroadcastReceiver br_ScreenOffReceiver;
#Override
public IBinder onBind(Intent arg0)
{
return null;
}
#Override
public void onCreate()
{
registerScreenOffReceiver();
}
#Override
public void onDestroy()
{
unregisterReceiver(br__ScreenOffReceiver);
m_ScreenOffReceiver = null;
}
private void registerScreenOffReceiver()
{
br_ScreenOffReceiver = new BroadcastReceiver()
{
#Override
public void onReceive(Context context, Intent intent)
{
Log.d(TAG, "ACTION_SCREEN_OFF");
// do something, e.g. send Intent to main app
}
};
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
registerReceiver(br_ScreenOffReceiver, filter);
}
}

I faced this issue recently. The BroadcastReceiver was working fine even if the app was removed from the background in the emulator and Samsung phones. But it failed to start my app in Chinese manufactured phones like Realme, Mi etc. While struggling to find a way to fix this I found that in the app details page there is battery optimisation settings where the Auto-launch feature was disabled. After I enabled it the app was working fine and BroadcastReceiver was able to start the app. I was unable ti find a way to enable this setting programmatically but I found this question which helped me direct the user to that setting page.

You can go through below solution;
Activity.java
Intent intent=new Intent(MainActivity.this,BroadcastService.class);
startService(intent);
BroadcastService.java
public class BroadcastService extends Service {
private static MusicIntentReceiver br_ScreenOffReceiver;
#Override
public IBinder onBind(Intent arg0)
{
return null;
}
#Override
public void onCreate()
{
registerScreenOffReceiver();
}
#Override
public void onDestroy()
{
}
private void registerScreenOffReceiver()
{
br_ScreenOffReceiver = new MusicIntentReceiver()
{
#Override
public void onReceive(Context context, Intent intent)
{
if (intent.getAction().equals(Intent.ACTION_HEADSET_PLUG)) {
int state = intent.getIntExtra("state", -1);
switch (state) {
case 0:
Log.e("AAAAAAAAAA", "Headset is unplugged");
break;
case 1:
Log.e("AAAAAAAAA", "Headset is plugged");
break;
default:
Log.e("AAAAAAAAAAAA", "I have no idea what the headset state is");
}
}
}
};
IntentFilter filter = new IntentFilter(Intent.ACTION_HEADSET_PLUG);
registerReceiver(br_ScreenOffReceiver, filter);
}
}
Menifest
<service android:enabled="true" android:name=".BroadcastService" />

Try this way..
Intent i = new Intent();
i.setAction("com.example.ali.rrr");
i.addFlags(Intent.FLAG_INCLUDE_STOPPED_PACKAGES);
i.setComponent(
new ComponentName("PackageNameApp2","PackageNameApp2.MainActivity"));
sendBroadcast(i);

Activity not found while using a service

I am trying to start a Service that implements SensorEventListener. I am getting an error in my logcat claiming:
android.content.ActivityNotFoundException:Unable to find explicit activity class
{com.devicemoved/com.devicemoved.ShakeWakeupService};
have you declared this activity in your AndroidManifest.xml?
My Service is declared in my manifest as shown:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.devicemoved"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.devicemoved.launcherGo"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service android:name="com.devicemoved.ShakeWakeupService" />
</application>
The Activity
public class ShakeWakeupService extends Service implements SensorEventListener {
private Context mContext;
SensorManager mSensorEventManager;
Sensor mSensor;
// BroadcastReceiver for handling ACTION_SCREEN_OFF.
public BroadcastReceiver mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// Check action just to be on the safe side.
if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
Log.v("shake mediator screen off", "trying re-registration");
// Unregisters the listener and registers it again.
mSensorEventManager.unregisterListener(ShakeWakeupService.this);
mSensorEventManager.registerListener(ShakeWakeupService.this,
mSensor, SensorManager.SENSOR_DELAY_NORMAL);
}
}
};
#Override
public void onCreate() {
super.onCreate();
Log.v("shake service startup", "registering for shake");
mContext = getApplicationContext();
// Obtain a reference to system-wide sensor event manager.
mSensorEventManager = (SensorManager) mContext
.getSystemService(Context.SENSOR_SERVICE);
// Get the default sensor for accel
mSensor = mSensorEventManager
.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
// Register for events.
mSensorEventManager.registerListener(this, mSensor,
SensorManager.SENSOR_DELAY_NORMAL);
// Register our receiver for the ACTION_SCREEN_OFF action. This will
// make our receiver
// code be called whenever the phone enters standby mode.
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
registerReceiver(mReceiver, filter);
}
#Override
public void onDestroy() {
// Unregister our receiver.
unregisterReceiver(mReceiver);
// Unregister from SensorManager.
mSensorEventManager.unregisterListener(this);
}
#Override
public IBinder onBind(Intent intent) {
// We don't need a IBinder interface.
return null;
}
public void onShake() {
// Poke a user activity to cause wake?
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// not used right now
}
// Used to decide if it is a shake
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() != Sensor.TYPE_ACCELEROMETER)
return;
Log.v("sensor", "sensor change is verifying");
}
}
The only thing I could possibly think of is that I am suppose to declare a broadcast receiver since I am using it in my class but I am not sure how to do that in this instance because I am not extending Broadcastreceiver.
I am calling this class from an activity with a button.
Any help will be great Thank You

You can already declared the package in the manifest tag, you should only need the .ShakeWakeupService part. Also make sure there is an empty constructor available for the system to construct your service

Sending data from service to activity

I am having issue when sending data from Service to Activity through Notification , I click a Notification an Activity get invoked but when i try to add some parameters through bundle i am not able to get the parameters in that called intent , I have gone through the link
How to send parameters from a notification-click to an activity?
But still no luck.
Has the same issue occurred with somebody else ?
Thanks in advance.

You have to modify the Manifest file as well.
Here is the example that works:
These variables and methods are members of Service class:
public static final String MOVEMENT_UPDATE = "com.client.gaitlink.AccelerationService.action.MOVEMENT_UPDATE";
public static final String ACCELERATION_X = "com.client.gaitlink.AccelerationService.ACCELERATION_X";
public static final String ACCELERATION_Y = "com.client.gaitlink.AccelerationService.ACCELERATION_Y";
public static final String ACCELERATION_Z = "com.client.gaitlink.AccelerationService.ACCELERATION_Z";
private void announceAccelerationChanges()//this method sends broadcast messages
{
Intent intent = new Intent(MOVEMENT_UPDATE);
intent.putExtra(ACCELERATION_X, accelerationX);
intent.putExtra(ACCELERATION_Y, accelerationY);
intent.putExtra(ACCELERATION_Z, accelerationZ);
sendBroadcast(intent);
}
And this are the methods from Main activity:
You have to register receiver in the onResume method:
#Override
public void onResume()
{
IntentFilter movementFilter;
movementFilter = new IntentFilter(AccelerationService.MOVEMENT_UPDATE);
accelerationReceiver = new AccelerationServiceReceiver();
registerReceiver(accelerationReceiver, movementFilter);
startAccelerationService();
super.onResume();
}
private void startAccelerationService()
{
startService(new Intent(this, AccelerationService.class));
}
public class AccelerationServiceReceiver extends BroadcastReceiver
{
#Override
public void onReceive(Context context, Intent intent)//this method receives broadcast messages. Be sure to modify AndroidManifest.xml file in order to enable message receiving
{
accelerationX = intent.getDoubleExtra(AccelerationService.ACCELERATION_X, 0);
accelerationY = intent.getDoubleExtra(AccelerationService.ACCELERATION_Y, 0);
accelerationZ = intent.getDoubleExtra(AccelerationService.ACCELERATION_Z, 0);
announceSession();
updateGUI();
}
}
This is the part of AndroidManifest.xml file that has to be set in order to receive broadcast messages:
<activity android:name=".GaitLink"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
<action android:name="com.client.gaitlink.CommunicationService.action.ACTIVITY_STATUS_UPDATE" />
</intent-filter>
</activity>