I would like to achieve fragments navigation like this: 
When I slide finger down somewhere on fragment A, fragment C will be opened (as slide movement), to go back to A slide finger up from C and so on...
I thought about custom ViewPager with vertical swipe direction but I have problem with "Open .." triangles, it should be shared between fragments end rotated during slide movement to change from for example "Open C" to "Open A". Any suggestions ? :)
Create anim folder in res folder. Create file named in_up
<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android"> <translate android:fromXDelta="-100%" android:toXDelta="0%" android:fromYDelta="0%" android:toYDelta="0%" android:duration="700"/> Create another file named out_down
<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android"> <translate android:fromXDelta="0%" android:toXDelta="0%" android:fromYDelta="-100%" android:toYDelta="0%" android:duration="700"/> To detect swipe left and right you can use this code.
Create variables
private float y1,y2; static final int MIN_DISTANCE = 150; And override onTouchEvent().
@Override public boolean onTouchEvent(MotionEvent event) { switch(event.getAction()) { case MotionEvent.ACTION_DOWN: y1 = event.getY(); break; case MotionEvent.ACTION_UP: y2 = event.getY(); float deltaY = y2 - y1; if (Math.abs(deltaY) > MIN_DISTANCE) { MyFragment myFragment = new MyFragment(); myFragment.show(this.getSupportFragmentManager(), "my fragment"); overridePendingTransition(R.anim.in_up, R.anim.out_down); } break; } return super.onTouchEvent(event); } 
This is what I would do:
Use this to listen to swipes
Make some adjustments to this , like enter_from_left would become enter_from_top and code inside changes from:
android:fromXDelta="-100%" android:toXDelta="0%" android:fromYDelta="0%" android:toYDelta="0%" android:duration="700"/> to
android:fromXDelta="0%" android:toXDelta="0%" android:fromYDelta="-100%" android:toYDelta="0%" android:duration="700"/> And make similar changes to other transition xml files.
Check which page I am on and accordingly call replaceFragmentWithAnimation when a swipe is detected.
i recommend to simply use Viewpager2 instead of the legacy ViewPager as ViewPager2 uses the recyclerview implementation under the hood so it supports vertical and horizontal swiping. check the documentation to understand how to migrate from ViewPager to ViewPager2
ViewPager, as "out-of-the-box" it has callbacks for scrolling, and is designed for flipping through Fragments ..ViewPager2(forget the oldViewPager) to achieve stable vertical paging. AndPageTransformerto put theOpenViews in between the fragments. Vertical paging with the oldViewPageris not working propery, because the privateslopeparameter is not well-set for different screen sizes (it's only good for hotizontal swipes). This is fixed withViewPager2(amongst other issues).