Viewpager.Setoffscreenpagelimit(0) Doesn't Work as Expected

ViewPager.setOffscreenPageLimit(0) doesn't work as expected

Does ViewPager require a minimum of 1 offscreen pages

Yes. If I am reading the source code correctly, you should be getting a warning about this in LogCat, something like:

Requested offscreen page limit 0 too small; defaulting to 1

TabLayout with ViewPager not working as expected

Its not possible when using ViewPager. ViewPager loads at least one right/left adjacent fragment of current fragment as per your swipe direction.

If you read the ViewPager documentation, there is a method ViewPager.setOffscreenPageLimit(LIMIT) which supports off screen page limit and its default value is 1.

SetOffscreenPageLimit:

Set the number of pages that should be retained to either side of the
current page in the view hierarchy in an idle state. Pages beyond this
limit will be recreated from the adapter when needed.

This is offered as an optimization. If you know in advance the number
of pages you will need to support or have lazy-loading mechanisms in
place on your pages, tweaking this setting can have benefits in
perceived smoothness of paging animations and interaction. If you have
a small number of pages (3-4) that you can keep active all at once,
less time will be spent in layout for newly created view subtrees as
the user pages back and forth.

You should keep this limit low, especially if your pages have complex
layouts. This setting defaults to 1.

See documentation.

Here are some related answers:

1. ViewPager.setOffscreenPageLimit(0) doesn't work as expected

2. How can make my ViewPager load only one page at a time ie setOffscreenPageLimit(0);

3. How does setOffscreenPageLimit() improve ViewPager performance by retaining more offscreen Fragments?

TabLayout with ViewPager not working as expected

Its not possible when using ViewPager. ViewPager loads at least one right/left adjacent fragment of current fragment as per your swipe direction.

If you read the ViewPager documentation, there is a method ViewPager.setOffscreenPageLimit(LIMIT) which supports off screen page limit and its default value is 1.

SetOffscreenPageLimit:

Set the number of pages that should be retained to either side of the
current page in the view hierarchy in an idle state. Pages beyond this
limit will be recreated from the adapter when needed.

This is offered as an optimization. If you know in advance the number
of pages you will need to support or have lazy-loading mechanisms in
place on your pages, tweaking this setting can have benefits in
perceived smoothness of paging animations and interaction. If you have
a small number of pages (3-4) that you can keep active all at once,
less time will be spent in layout for newly created view subtrees as
the user pages back and forth.

You should keep this limit low, especially if your pages have complex
layouts. This setting defaults to 1.

See documentation.

Here are some related answers:

1. ViewPager.setOffscreenPageLimit(0) doesn't work as expected

2. How can make my ViewPager load only one page at a time ie setOffscreenPageLimit(0);

3. How does setOffscreenPageLimit() improve ViewPager performance by retaining more offscreen Fragments?

ViewPager activates its fragments before usage

ViewPager will initialize two fragments minimally.
ViewPager allows us to set setOffscreenPageLimit(), but it require at least 1, so it will initialize first and next fragment.
Read more here ViewPager.setOffscreenPageLimit(0) doesn't work as expected

Try to invoke code in fragments by setting onPageChangedListener() in MainActivity, so you can execute code when user swiped/opened fragment.



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