Google engineers seem to agree with this belief as well. In general, the best way to avoid the exception in these cases is to simply avoid committing transactions in asynchronous callback methods all together. The system makes the following calls: setUserVisibleHint() // before fragment's lifecycle calls, so presenter is nullįragment already created and home button is pressed. A FragmentTransaction is committed inside the onPostExecute method, causing an exception to be thrown. Let’s start, Create a simple Viewpager 1 2 3 4 <4.view. If you are looking for ready to use solution is much better to use this tiny library. ViewPager is most often used in conjunction with Fragment, which is a useful way to supply and manage the lifecycle of each page. This article describes how our Fragment Back works under the hood.

SetUserVisibleHint() is not enough, we've detected 3 different cases that needed to be addressed ( onAttach() is mentioned so that you know when the presenter is available):įragment has just been created. By the implementation of a PagerAdapter, we make the views which allows the user to flip left and right through pages of data.

We have a special case with MVP where the fragment needs to notify the presenter that the view has become visible, and the presenter is injected by Dagger in fragment.onAttach(). The user interface for the first fragment will contain a toolbar of sorts consisting of an EditText view, a SeekBar and a Button, all contained within a.

Android studio fragment visible