Android ViewPager2 - how to detect user initiated page change

Question

I have the ViewPager2 callback setup but need to detect when a user initiated page change has completed. The callback won't differentiate between user initiated and code initiated. Here's what I have now:

ViewPager2.OnPageChangeCallback swipeListener = new ViewPager2.OnPageChangeCallback() { @Override public void onPageSelected(int position) { //I want to run code only if user initiated this page change //but this runs whether user initiated or code initiated } }

The page change that is done via code:

viewPager.setCurrentItem(targetSlide);

The docs for ViewPager2 show a isUserInputEnabled() method which tells you if a user "can" change the page manually, but I need to detect if the user "did" initiate the page change.

Pavneet_Singh · Accepted Answer · 2020-06-25 13:36:16Z

3

You can use isFakeDragging inside registerOnPageChangeCallback to detect whether the drag is fake or initiated by user.

Returns true if a fake drag is in progress.

...onPageScrolledonPageScrolled(int position, float positionOffset, int positionOffsetPixels){ if(isFakeDragging) {// fake scroll} else{// user scroll} }

edited Jun 25, 2020 at 13:36

answered Jun 25, 2020 at 13:00

Pavneet_Singh

37.5k5 gold badges57 silver badges71 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

lilbiscuit Over a year ago

I don't initiate a fake drag in code to change the page, so isFakeDragging will always return false here.

Pavneet_Singh Over a year ago

then what do you mean by code initiated? you need to add the complete details about your use case. Anyhow, if possible, use fake drag for best practices and desired behavior.

lilbiscuit Over a year ago

OP edited. I am using viewPager.setCurrentItem().

Pavneet_Singh Over a year ago

@lilbiscuit then the easy solution is to use a boolean flag to track the change or the other option is to use a touch event listener to detect the user touch and proceed accordingly.

NobleUplift Over a year ago

How do you use the position to get the view that the viewPager2 is looking at?

sideshowbarker · Accepted Answer · 2023-05-20 22:10:19Z

One can override viewpager2 to detect a page change like so:

 viewPager.registerOnPageChangeCallback(new ViewPager2.OnPageChangeCallback() { @Override public void onPageSelected(int position) { } });

Collectives™ on Stack Overflow

Android ViewPager2 - how to detect user initiated page change

2 Answers 2

5 Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

5 Comments

Comments

Related