Develop Reference

Android Cancel Notification From Backend

I noticed that some app like messenger clear their notification in phone even I viewed the message from web.I know it can be done by giving ID to notification when showing it and when it needs to be cleared we can send another event via FCM and clear the corresponding notification. Is there a proper way of doing it other than sending another event via FCM because it feels not the proper way of doing it for me.

I hope it will helpful Can you expire / remove a message remotely on FCM?.
Note: due to low reputation I had to use answer section instead of comments.

Choose to show or ignore push notifications client side?

We want to send push notifications in Android and iOS to a group of users that match a certain condition. We can check if an user match this condition calling an API.
Our problem is that the users information changes very quickly and we don't have any way to keep track of this in our push notifications engine (OneSignal).
The only alternative we can think is to send the push notification to all users and client side call the API to get the latest user information. Depending on this we could choose to show the notification or ignore it.
Is this possible on Android and iOS?

It is 100% possible for sure. in the receiver class you call an intentservice, which can hit an api and get the latest information, based on the information you create notification using notification builder, and avoid if you dont want.

Yes, with the help of NotificationExtenderService this is possible.
Receive a notification in the background. Notification data is wrapped up in OSNotificationReceivedResult object. Now, read the notification id/title which should be unique for every notification.
Send this unique notification title/id along with user id to an API, which will return whether to show the notification to the user or not. If true then read notification title and message/description from OSNotificationReceivedResult and make a notification via NotificationCompat otherwise just ignore it.
Reference

Can we perform an ACTION programmatically on a Notification from Notification Listener Service?

Is it possible to invoke an ACTION programatically on a Notification from a NotificationListenerService?
I have written a Notification Listener service that reads out all the incoming notifications and dismisses when done. But I'm not sure if we can perform any ACTIONs on the incoming notifications.
For eg: On a WhatsApp message notification I can read the package name, sender and message details but is there a way to send a reply back to the sender?
Currently Android Wear is doing this so I'm wondering if it is following a generic approach of acting upon a Notification or it has a specific API to WhatsApp service.

When ever a whatsapp notification is received via notification listerner service there is one another notification thats received (hidden) which has a tag value something like this XXXXXXX#s.whatsapp.net (xxxxxxx being the phonenumber), I think this somehow holds the key to sending a reply to this user.
I am working on other app logic, which does not require you to send back replies but I found this interesting but could not get enough time to check it myself.

Yes, you can do it by this function:
sbn.notification.actions[0].actionIntent.send()

Yes, we can perform actions on notifications. Pushbullet app on Android has an ability to reply to WhatsApp, Hangouts, Facebook messenger etc when user enters the message form desktop which means that there is a way. I am still trying to figure out how to do it.

To retrieve incoming notification details from whatsapp in android

How can I retrieve the name, message and time for any incoming notification on "whatsapp". Basically, I want to add up all incoming notification details in an array list. Please help me to get the explained code for the same.

You are trying to catch a 3rd party notification which requires a little more work. This SO question might help you to the right track.
How to get notified when a notification is notified

I was able to do this using Accessibility Service . Using this, you can listen to all notification on the notification bar. I listened to application-specification by adding the package name to the Accessibility Service service info , which in this case was com.whatsapp. I couldn't read the messages, but I get notified whenever a message arrives.
http://developer.android.com/training/accessibility/service.html#create

Handling Parse Push Notifications in Android

I am using Parse API in order to handle push notifications. In our Android application, I want to accomplish two things:
1) If we have received a Push Notification with the application is closed and the user clicks on the notification, I want to be able to understand that the application is being opened via a push notification.
2)If we receive a push notification while the application is open, I want to handle this and do some extra work.
In both cases, I want to be aware that the application has received a push notification in order to execute some special operations.
As far as I understand from Parse API documentations, it offers two methods of handling pushes: Responding with an Activity and Responding with an Intent. I am currently calling
PushService.setDefaultPushCallback(context, MainActivity.class);
in my Application class with needed changes in the AndroidManifest.xml file and already receive push notifications, this corresponds to Responding with an Activity method. But I don't know how to be aware of Push Notifications explicity with this method.
Thanks in advance.

When a push is received ,Check
1:Whether our application is in foreground or background.
If it is foreground, that means app is visible and do your stuff(show alerts or anything you want).
If app is in background,that means it is not visible and if you want to do any thing based on this.
i hope this helps..