Develop Reference

How to execute some event if RN has been killed?

Not sure if I understand correctly but according to this link
Deliver silent notifications and wake up your app in the background on the user's device.
It sounded to me that it's possible to perform some action even if the app has been killed.
Currently I'm using OneSignal as below:
OneSignal.addEventListener('received', this.onReceived);
onReceived(store, notification) {
store.dispatch(receivedNotification({ notification }));
}
However the above will only be able to dispatch action if the app is in background or foreground, but once the app been killed, despite receiving notification successfully, onReceived event will not be fired.
So my question is whether is it possible to "wake" my RN app in the background and dispatch a redux action?

There is no event that you can catch before app is killed. You also cannot prevent the user from killing your app. And once it is killed you cannot 'wake' it up, as your code is not running. You can only do such tasks when the app is in the background/foreground.

Yes, it is possible you can execute some event if RN has been killed.
now the question is how basically I am also using react-native and I have got some challenges also, I also want to execute some event if RN has been killed, but I did not get any answer actually my concern is to open an app which can and show a call screen when calling notification is received so I dig a lot and I found a solution,
first I created a bridge connection between javascript to java and then write a wakeful service which gets called every time when we receive notification and then I call my background intent service and in this service I wake up my activity and set some flags which help me to open screen when screen is lock depends on the conditions
// receiver Service //
public class MessagingService extends WakefulBroadcastReceiver {
private static final String TAG = "FirebaseService";
#Override
public void onReceive(Context context, Intent intent) {
Log.d(TAG, String.valueOf(!isAppOnForeground(context)));
if (intent.getExtras() != null) {
if (!isAppOnForeground((context))) {
//This get called every time you receive notification
}
}
}
private boolean isAppOnForeground(Context context) {
ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
List<ActivityManager.RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();
if (appProcesses == null) {
return false;
}
final String packageName = context.getPackageName();
for (ActivityManager.RunningAppProcessInfo appProcess : appProcesses) {
if (appProcess.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND && appProcess.processName.equals(packageName)) {
return true;
}
}
return false;
}
}

How to know when I close my app?

My question is simple, I tried disable the bluetooth for my app when the user close the app.
I need that if the user is with the app in background, the bluetooth maintain active, but if the user slide the app out of screen, the bluetooth closes.
I know how disable the bluetooth.
if (mBluetoothAdapter.isEnabled()){
mBluetoothAdapter.disable();
}
Works perfectly, but I need call that 3 lines when the user close the app, I tried with onDestroy, onPause, onStop, but noone works for me.
onDestroy method is called when the user touch back button and the task go for background.
onPause method is called when the user touch the recents button, but the app is not closed.
onStop method same of onPause.
So... How to know when the user close the app?
Thank you

You can write a method to check if the app is running in background or not.
private boolean isAppIsInBackground(Context context) {
isInBackground = true;
ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT_WATCH) {
List<ActivityManager.RunningAppProcessInfo> runningProcesses = am.getRunningAppProcesses();
for (ActivityManager.RunningAppProcessInfo processInfo : runningProcesses) {
if (processInfo.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
for (String activeProcess : processInfo.pkgList) {
if (activeProcess.equals(context.getPackageName())) {
isInBackground = false;
}
}
}
}
} else {
List<ActivityManager.RunningTaskInfo> taskInfo = am.getRunningTasks(1);
ComponentName componentInfo = taskInfo.get(0).topActivity;
if (componentInfo.getPackageName().equals(context.getPackageName())) {
isInBackground = false;
}
}
return isInBackground;
}
This method returns true if the app is running in background.Then you can enable or disable bluetooth accordingly.
Also you can set a flag in your onResume and onPause methods of the BaseActivity which is extended by all other activitues so that you can check the flags to know whether app is running or not.

Make a BaseActivity and override its OnPause() method and extend
every Activity from BaseActivity .
I would also like to mention that onPause() is fired even when switching between multiple activities, so you'd need to track when it's pausing to go to another screen.
Reference : http://developer.android.com/reference/android/app/Activity.html#ActivityLifecycle

If you want Bluetooth disabled when the user exits your activity, disable it in onBackPressed().

Check application is minimized/background

I am so surprised!
Because not able identify application currently in foreground or background,
when i pressed home button and my application is not in foreground. then after i have used to check application running in foreground or not.
public boolean isAppOnForeground()
{
ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
List<RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();
if (appProcesses == null) { return false; }
final String packageName = context.getPackageName();
for (RunningAppProcessInfo appProcess : appProcesses)
{
if (appProcess.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND && appProcess.processName.equals(packageName)) { return true; }
}
return false;
}
it will returns always true even if my application actually not in foreground.
Note:
My application have 2 services,
1 service will be canceled when application is removed from recent task list( that i have achieved.)
2 service will be canceled when application goes in background. (that is check wifi signal strength.)
how to know app is foreground or background?
how to stop service when application is not in foreground?

Rely on Activity callback methods, such as onPause(), onStop() and onResume(), that will give you hints on the current state of Activity. The Activity reference gives a very broad explanation of every of those methods.

try handling onpause() event of activity class. Onpause is called when activity goes out of focus.

Toggle Service Activity

I'm developing a service that need to run foreground, and users can toggle it on/off through an activity. So basically, the activity MAY be killed, but the service is safe as long as it is not stopped by user.
However, I'm getting this trouble: how to turn off the service if it is on? That mean, if my activity was killed, then restarted, so I get no reference of the started service intent to call stopService.
Below is my current code. It works fine if the user call deactivate after the service is started by the same activity. The button status is always correct, but when my activity is restarted by the OS, this.serviceIntent is null.
protected boolean isServiceRunning() {
ActivityManager manager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
for (RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
if (SynchronizationService.class.getName().equals(service.service.getClassName())) {
return true;
}
}
return false;
}
#Override
protected void onResume() {
super.onResume();
this.togglingByCode = true;
this.butActivate.setChecked(this.isServiceRunning());
this.togglingByCode = false;
}
public void onActivateButtonClick(final boolean pIsChecked) {
if (this.togglingByCode) { return; }
if (pIsChecked) {
this.saveSettings();
this.serviceIntent = new Intent(this, SynchronizationService.class);
this.serviceIntent.putExtra(KEY_WEBSERVICE, this.txtWebService.getText().toString());
this.serviceIntent.putExtra(KEY_PASSWORD, this.txtPassword.getText().toString());
this.serviceIntent.putExtra(KEY_INTERVAL, Integer.parseInt(this.txtRefreshInterval.getText().toString()));
this.serviceIntent.putExtra(KEY_TIMEOUT, this.preferences.getInt(KEY_TIMEOUT, DEFAULT_TIMEOUT));
this.serviceIntent.putExtra(KEY_RETRY, this.preferences.getInt(KEY_RETRY, DEFAULT_RETRY));
this.startService(this.serviceIntent);
} else {
this.stopService(this.serviceIntent);
this.serviceIntent = null;
}
}
Please tell me how to stop the service correctly. Thank you.
P.s: I know a trick that make serviceIntent static, but I don't feel safe about it. If there is no any other way, then I will use it.

Simply initialize your serviceIntent in the activity's onCreate... You can start your service, kill your activity, reopen it and stop the service with the same serviceIntent.

Android: check if my Service is running in the background

I am running a Service to get Notifications every 1 hour in my application.
The service definitely runs every 1 hr; I checked it using the Logcat.
But since I am starting this Service in the onResume() of my MainActivity, I want to check whether the Service is already running, and start it only if it's not running.
I used this code:
private boolean isMyServiceRunning() {
ActivityManager manager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
for (RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
if ("com.android.MyApp.MyServices.NotificationsService".equals(service.service.getClassName())) {
return true;
}
}
return false;
}
But I always get false.
So I checked what output service.service.getClassName() gives. And my Service is not there in the list.
Is it because my application is unknown? or something else?

I know its bit late but this answer might help others who are looking for the same.
Have you started your service by using context.startService()?
Make sure that the manifest file contains following:
<service android:name="com.android.MyApp.MyServices.NotificationsService" />

private boolean isMyServiceRunning(Context mContext) {
ActivityManager manager = (ActivityManager) mContext
.getSystemService(Context.ACTIVITY_SERVICE);
for (RunningServiceInfo service : manager
.getRunningServices(Integer.MAX_VALUE)) {
if (**HERE_YOUR_SERVICE'S_CLASS_NAME**.class.getName().equals(
service.service.getClassName())) {
return true;
}
}
return false;
}
// i have background GPS service and i have successfully checked that my GPS service is either running or not.
// Happy coding...