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I'm having difficulty understanding the lifecycle of my fragment when the same fragment is created across three tabs. The main widget in each fragment is an EditText object that that is tracked in a class I created, one per tab, created when my app first executes. When the app executes the input (which is provided by buttons on the screen, not a keyboard) sets text into the second tab's EditText.

The input appears to be following getItem() inside my FragmentPagerAdapter. I understand that getItem() is called twice when my tabs are created and that this is perfectly normal behavior but what I'm not understanding is if this is a focus issue or a logic issue with my code design (I'm hoping the former). Could it have to do with instantiate() being returned by getItem()? Once instantiate() is called, does focus always follow it since I have this line of code in the onCreateView() of my fragment?

active.editLine = (EditText) v.findViewById(R.id.display);
// active is the currently active object of my app's class.

The reason I suspect instantiate() is causing my error is because when I increased the rendering of pages via setOffscreenPageLimit(2) the text was being sent to the third tab.

At this point I tried to track what was happening where and it was a nice educational exercise. What I found in my struggles was this is probably a focus issue-- however my attempts at clearing focus and setting focus did not appear to be applied, nor am I even sure if that's the underlying issue. I ended up using active.editLine.debug(0) to see if focus was being lost or gained and it wasn't. I read some of this fairly popular post and took my focus out of my XML but that didn't help either.

Just to make sure, where should I be setting my EditText objects? In OnCreateView() in my fragment? That is where the above code currently lives. I create three objects of my custom class in my activity as global variables. I have getters and setters in what I feel are appropriate areas of my code. Should the above code instead live in onCreate() of my fragment? If you think this is a focus issue, what is the accepted method of turning off focus and only using it when I need it? More importantly, when my app first runs, where do I turn on focus? OnTabSelected() is called before getItem() runs twice to render the first two tabs. So where would I gain initial focus if I'm globally turning it off? Can set focus with a type of listener?

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Steven
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1 Answers1

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Not exactly sure what you're going for here, but here are some suggestions:

  • have your global active object live in the main activity and call getActivity().someObject from your fragments
  • findViewById() will search down the view hierarchy until it finds the first instance of R.id.display
  • your fragment views won't be available until you commit them with a fragment transaction, this means that their views also won't be available until that time
  • you are "scoping" findViewById() to some view v by calling v.findViewById()
  • if you are paging through fragments, perhaps try setting your active view in the fragment's onResume() method
  • the fragment's onCreateView() method is only called once. This will be called between onCreate(Bundle) and onActivityCreated(Bundle).
nickaknudson
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