How to enable split screen in my Android app?

I want to enable Split Screen for my android app. If I try to drag my app to make it occupy the top half of my android device it gives the message "App doesn't support split screen". However, for other apps such as Facebook and WhatsApp, I am able to use split screen. I am using LGE Nexus 5X with Android 7 (nougat) which supports split screen.

Two apps running side-by-side in split-screen mode.

How do I force an app to split screen on Android?

Step 1: Tap & hold the recent button on your Android Device –>you will see all the recent list of applications listed in chronological order. Step 2: Select one of the apps you wish to view in split screen mode –>once the app opens, tap & hold the recent button once again –>The screen will split into two.

Add this to your application or activity tag in AndroidManifest.xml:

android:resizeableActivity=true

Adding it to application will make all activities realizable, while adding it to a specific activity will keep other activities incompatible with resizing.

If your targetSdkVersion is 24 (Nougat) or higher, this will be set to true by default (you can still turn it off by setting the param to false).