A POC to show how to have multiple ViewPagers work in Parallax effect with each other

Code is based on this StackOverflow post: http://stackoverflow.com/q/31138652/878126

Here's how it looks like:

Currently, because there is an issue (read below), I didn't put an official release, but you can still use Gradle in case you don't care or can't reproduce the issue in your app (link here) :

repositories {
	    maven {
	        url "https://jitpack.io"
	    }
	}

dependencies {
	        compile 'com.github.AndroidDeveloperLB:ParallaxViewPagers:19516eb03a'
	}

Just prepare the viewpagers, and for each "viewPager" that you need to allow to affect "viewPager2" , use:

viewPager.addOnPageChangeListener(new ParallaxOnPageChangeListener(viewPager,viewPager2,masterRef));

where "masterRef" is a shared AtomicReference variable that's used to decide which of them is the current "master" to affect the others.

Example of 2 ViewPagers, each can affect the other:

AtomicReference<ViewPager> masterRef=new AtomicReference<>();
viewPager.addOnPageChangeListener(new ParallaxOnPageChangeListener(viewPager,viewPager2,masterRef));
viewPager2.addOnPageChangeListener(new ParallaxOnPageChangeListener(viewPager2,viewPager,masterRef));

Sometimes, the other ViewPager might have a "flashing" effect. A workaround for this, is to pass the touch events from the container of the various viewpagers, to the master viewpager.