I'm new in using view pager, I've done everything correctly, I conveted my activities into fragments and put them in FragmentPagerStateAdapter.
When testing it in the emulator, what I noticed is that the onCtreate to the onResume are called one fragment before the actual visibility on the view pager - it makes sense, the device wants to get ready for the next step, but the problem is that I have one fragment which calls a dialog every onStart so that actually happens on the wrong fragment.
What should be done?
You can use an OnPageChangeListener on your ViewPager to detect when you navigate to the right fragment.
Related
I am working on view pager and loading fragments.and I am using fragment pager adapter.Problem i have 6 fragments.If i go to fourth fragment and i go to first fragment,my first fragment destroyed and restarted again.I dont want to restart the fragments again.How to stop destroying the fragments.I am using viewpager.setOffScreenLimit also.My fragments not restarting ,then problem its not calling any methods in onCreateView.How to solve this problem.I want six slides(Introslider).if i go back and next i need to get previous and next data.
Move your code of onCreateView() method to onUserVisibleHint() method.
From Android Developer Site
setUserVisibleHint(boolean isVisibleToUser)
Set a hint to the system about whether this fragment's UI is currently
visible to the user.
I'm using a ViewPager in my app. There are three fragments inside the PageAdapter that is set in the ViewPager. All works perfectly fine and I can switch between all three fragments. I have 3 buttons that allow me to switch between adapters 1 to 3. The problem is noticed when I click buttons 1 and 3 at the same time. Here's what happens:
Fragment 1 - Fragment 3
onAttach
onViewCreated
onResume
onPause
onAttach
onViewCreated
onResume
onPause
As you can see from above, the second fragment is never paused and therefore never resumed. Both fragments modify the same recycler view onResume so with the behaviour above I end up with the incorrect state of my recycler view.
Any thoughts on why this might be happening and how I can fix this?
A ViewPager loads (by default) the current page, the previous page and the next page, since you have only 3 pages the second fragment is always resumed.
the solution is to set up a OnPageChangeListener and modify the recycler view in onPageSelected instead in onResume
I am trying to implement swipe views with 2 tabs. For that, I am using view pager with 2 fragments. Now, the problem is that as soon as the main activity is opened (that contains those two tabs), onCreateView function is called for both the fragments. Please help me as how can I avoid calling of onCreateView of second fragment when one is in use.
Thanks,
Arpit
ViewPager retains the fragment to the left and to the right of the current view by default. This is to reduce a choppy user experience - that way you can begin swiping left or right and immediately see what is there without delay.
It is possible to disable (or increase the number of fragments to be retained) with setOffscreenPageLimit(0), but seriously consider if this is the right approach.
while using View pager, I face a strange problem.
In my project i have three fragment in a view pager, but while loading the second fragment by swiping from left to right , the OnCreate of third Fragment is automatically calling.in onCreate method i called an Api for getting some data.hence the Api is also called.Normal scenario is like that it only called while loading third fragment by swiping from left to right.
Thanks in Advance
View pager works same as listview.
It have same buffer of fragments to increase the UI experience.
so it creates fragments in advance and show to he user when asked.
so use http://developer.android.com/reference/android/support/v4/view/ViewPager.OnPageChangeListener.html
for your purpose.
Thanks
I have a custom widget that performs FragmentTransaction.replace when buttons are pressed. Currently, my code is set up such that the first time a fragment is created, it attaches a bunch of stuff to the view that isn't originally part of the xml layout file.
When the app first launches, all my fragments show stuff correctly, however, let's say I start on Fragment A. I can then transition to Fragment B (with B showing up correctly), however, when I transition back to Fragment A, all the stuff I have attached to the view of Fragment A is now gone. I know this happens because onCreateView is called which probably means the Fragment's view is re-generated when FragmentTransaction.replace is called.
Is there a way where I can keep my fragments around instead of having them re-generate their views when FragmentTransaction.replace is called?
Thanks!
Instead of using fragmentTransaction.replace, use fragmentTransaction.show and fragmentTransaction.hide.
That will keep your fragments from being destroyed.