I am having an issue here that is driving me nuts. What I have is the following:
FragmentActivity1 holds the viewPager. It instantiates the FragmentAdapter and two fragments and attach them to the ViewPager.
Fragment1 has only one button. When user clicks this button, I create one Intent and invoke a FragmentActivty. This fragmentActivity contains a form, which the user fills in and press OK. When he does that, I persist the data in the DB of the app.
Fragment2 is a ListFragment, and lists all the data that was inserted previously by the user.
By the time user completes the form and presses OK, I persist the data, like I said and finish() the activity, returning to Fragment1. WHen I swype to Fragment2, the data is not there. I need then to swype to Frag1 and then back to Frag2. Only then I can see the problem.
I have tried setting listeners between activities and fragments but, still, cant make this work.
Have anyone seen? I am willing to share my small project as well, so you guys can take a look.
Thanks,
Felipe
I usually fill my ListView in onResume() in the ListFragment. When I'm done adding new stuff to the list (In a seperate FragmentActivity, just like you), the ListView automatically gets refreshed, because onResume() gets called ;)
Another approach is using onActivityResult(), then you can update list only when something new is added or something is removed
Related
There are some posts here related to this issue, but I am trying to figure out what is going on in my particular case. Basically I have an Activity that instantiates a ListFragment to display a list of items that the user can scroll. When a list item is selected, I launch a separate Activity that "takes over" the screen to display details of the selection.
The issue is that when the Back button is pressed in this 2nd activity, the ListFragment's list is again displayed, but it's always repositioned to the top of the list, and I can't figure out how to correctly get the previous state of the list so that I could reposition it with setSelection, etc.
I do have a saveInstanceState in the fragment and it is being called when the details activity is launched, just as I would expect. However, I can't see any obvious fragment method that will be called to receive this Bundle back when the details activity returns. onCreateView and onViewCreated are not called again, and I can't use onViewStateRestored since I'm targeting API 14 (if that's even applicable).
Any ideas? This has to be something pretty basic that I'm missing!
The call to the deprecated startManagingCursor was the cause. I removed it and everything works fine. There was no need to get into a CursorLoader since I am using a simple CursorAdapter with a local SQLite database.
I've implemented a NavigationDrawer within the MainActivity which containts two Fragment. The second Fragment contains a ListView that opens a new Activity (onItemClick) that shows the according detailed data. (I guess that's pretty much the master/detail flow).
When I use the up button to navigate back I got shown the first fragment and not the second fragment with the ListView.
Any ideas how to solve that problem?
Make method in MainActivity for example setFragment(int whichFragment);
and set fragment you want in it, you should already have code that do that and than call that method in onBackPressed() method.
For your question about another fragment, well it depends on how your master/detail flow is suppose to work, it is not a problem to use another activity if you dont need left menu any more, but if you do need left menu then use another fragment.
Best regards
Scenario:
I have a fragment which has a ViewPager which contains 5 instances(different) of a single Fragment with different values, each having a listivew that contains some sort of items.
Problem:
The flow goes smooth when I click an item of listView(say on page1) but the moment I come back from there on pressing back (overridden OnBackPressed in the main_activity (will discuss later)), the viewPager fails to load the subFragments.
But when I switch to the 2nd or 3rd page, it gets displayed, and on going back to 1st page, it now gets displayed.
OnBackPressed():
I am maintaining a manual stack here. When I click on an item of ListView, the current Fragment Instance (of the parent Fragment ofcourse) goes into stack. And when user comes back , that instance gets popped off the stack and I replaces it on the activities FrameLayout container.
References:
Fragments not getting recreated by FragmentStatePagerAdapter after coming back to the main Fragment instance
Guys, I am really pissed off here, please help me out.
Frankly, I haven't worked much with fragments.
But it seems like the page is being thrown off the memory every time you switch to other pages. I am not sure but if there is a way for android to manage this and keep the page in its memory persistently, it might solve the problem
Finally I am able to get a workaround for this issue, which included two things:
while replacing the fragment make a call to
ft.replace(R.id.content_frame, frag).addToBackStack(null);
while initiating the ViewPager, the fragment manager to be used is :
mAdapter = new myAdapter(getChildFragmentManager());
Actually the problem is that, android fails to recognise and load the older instance of the fragment unless you explicitly add that instance to the backstack. So after adding it to BackStack, there is practically no need to maintain your own manual Stack, but you still can do that.
I am building an app that consists of actionbar with tabs, and each tab consists of a fragment. One of the fragments has data that need to be loaded. So I want the data to be loaded only the first time. When the user changes the tabs and goes back to the one containing that fragment, doesn't wait for the data to be loaded again. I assume I have to use some kind of saving the data so that it can be used the next time the user goes back to that particular fragment. But I just do not know what method I should use. If someone knows or can suggest an example of saving fragment state, please let me know. Thank u!
Try this:
myFragment.setRetainInstance(true);
It'll mean the fragment isn't recreated every time it's added.
I am trying to update my listfragment when a button is pressed. the button puts a name into a database but how do I update the list so that name appears? the listfragment uses a cursorLoader to load from the database. I even tried using a content observer on the database and calling getLoaderManager().restartLoader() but that didnt work either.
So what can I do to update the list when I click a button in an activity? I have found very little information on this please help
I can't be sure, but I assume there is something weird going on with the interaction between your Fragment and your Activity, which you are apparently displaying simultaneously somehow. Is there any reason why you are listening for the Button in the Activity? Are you dealing with a multi-pane screen or something? It seems like it'd be a lot simpler to just have the Fragment deal with this itself (since it is the one implementing the LoaderCallbacks, I assume).
Also, be sure that you are implementing your Fragment lifecycle correctly... i.e. you call initLoader() and set the list's adapter in onActivityCreated() as opposed to onCreate().
Hope that helps!