Handle Fragment On Screen Orientation Changes? - android

I am useing This Sort of Code To Handle Three Fragment in Main Activity ...
FragmentA is Fixed it One Frame .. I change FragmentB and FragmentC on Button Click on FragmentA.
his Code is Running well either in Portrait or Landscape view .Here is The Code bellow.
public class MainActivity extends FragmentActivity implements
OnSwitchClickListener {
FragmentManager manager;
FragmentA fragA;
FragmentB fragB;
FragmentC fragC;
boolean fragBSet = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fragA = new FragmentA();
fragB = new FragmentB();
fragC = new FragmentC();
manager = getSupportFragmentManager();
FragmentTransaction ft = manager.beginTransaction();
ft.add(R.id.a_container, fragA, "frag A");
if (fragBSet) {
ft.add(R.id.bc_container, fragC, "frag C");
} else {
ft.add(R.id.bc_container, fragB, "frag B");
}
fragBSet = true;
ft.commit();
}
#Override
public void onSwitchClick(View v) {
Toast.makeText(getApplicationContext(), "Switch clkick from Activity",
Toast.LENGTH_LONG).show();
FragmentTransaction ft = manager.beginTransaction();
if (fragBSet) {
ft.remove(fragB);
ft.add(R.id.bc_container, fragC, "frag C");
fragBSet = false;
} else {
ft.remove(fragC);
ft.add(R.id.bc_container, fragB, "frag B");
fragBSet = true;
}
ft.commit();
}
This Code is Running well either in Portrait or Landscape view ... But When Ever I change the Orientation The Two Fragments Override One Another.
Need Solution.


When your orientation change, your Activity is recreated.
"In the scenario where a user rotates their device, Android will destroy your
application’s activity(s). Before destroying them it calls, onSaveInstanceState,
allowing developers to persist data. Once the activity is recreated post
rotation, the OS will call onRestoreInstanceState giving developers a chance to
restore the application state pre-rotation."
You should try to save your Fragments State.
putFragment: Put a reference to a fragment in a Bundle. This Bundle can be persisted as saved state, and when later restoring getFragment(Bundle, String) will return the current instance of the same fragment.
#Override
protected void onSaveInstanceState(Bundle outState) {
FragmentManager manager = getFragmentManager();
manager.putFragment(outState, MyFragment.TAG, mMyFragment);
}
getFragment: Retrieve the current Fragment instance for a reference previously placed with putFragment(Bundle, String, Fragment).
private void instantiateFragments(Bundle inState) {
FragmentManager manager = getFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
if (inState != null) {
mMyFragment = (MyFragment) manager.getFragment(inState, MyFragment.TAG);
} else {
mMyFragment = new MyFragment();
transaction.add(R.id.fragment, mMyFragment, MyFragment.TAG);
transaction.commit();
}
}
restoreFragment:
#Override
protected void onRestoreInstanceState(Bundle inState) {
instantiateFragments(inState);
}
Hope this helps.

Related

onBackPressed with fragments and saving fragment state

I want to save fragment state so I use fragment .add() and fragment .show() methods.
the part I use to add fragments in my mainActivity is
android.support.v4.app.FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.add(R.id.main_content, fragment, CURRENT_TAG);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
On back pressed in the fragment and getting back to it the get fragment by tag returns null
if (getSupportFragmentManager().findFragmentByTag(CURRENT_TAG) != null) {
drawerLayout.closeDrawers();
Runnable mPendingRunnable = new Runnable() {
#Override
public void run() {
android.support.v4.app.FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.setCustomAnimations(android.R.anim.fade_in, android.R.anim.fade_out);
hideTransactions(CURRENT_TAG);
fragmentTransaction.show(getSupportFragmentManager().findFragmentByTag(CURRENT_TAG)).commit();
}
};
although onBackPressed the state of the fragment is right(TAG_PREV returns not null) in the on back pressed method
#Override
public void onBackPressed() {
if (drawerLayout.isDrawerOpen(GravityCompat.START)) {
drawerLayout.closeDrawers();
return;
}
if (CURRENT_TAG == TAG_HOME) {
return;
}
navItemIndex = 0;
TAG_PREV = CURRENT_TAG;
CURRENT_TAG = TAG_HOME;
loadHomeFragment();
super.onBackPressed();
}

addToBackStack saves the transaction, in this case: fragmentTransaction.add(R.id.main_content, fragment, CURRENT_TAG); and when you press back(onBackPressed) you are reversing that transaction. So that will imply you are removing the previously added fragment.

It is not possible to maintain entire fragment in back stack, There is no provision given by android teams.
You have to use onSaveInstanceState for saving current state/data when you are leaving fragment.
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
Log.i(TAG, " onSaveInstanceState.");
savedInstanceState.putString("greeting", "Hello");
}
After that when again coming on that fragment you have to use.
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String greeting = (savedInstanceState != null) ? savedInstanceState.getString("greeting") : "null";
Log.i(TAG, " onCreate: " + greeting);
}
Please let me if it dosen't work for you.

Fragments stack Android

Imagine one activity with 3 fragments: starts showing the first one, select a menu option and go to the second one, select another option and go to the 3rd fragment and select again the first option an return to the second one.
f1 -> f2 -> f3 -> f2
When I press back I want the app returns to fragment 3 and when I press back again it should return to fragment 1 and if press back again, close the app.
Something like if the fragment exists, move it to top of the stack and if not, create it.
Thank you!

Here is solution I came up over time.
The idea is following, you need to keep a stack data structure and whenever you add a fragment add it to stack as well, then override onBackPress method and check if stack is not empty then replace your fragment container with new fragment from top of the stack when it is empty do super.onbackpress
So here is a parent class for all kind of fragment based navigation.
public abstract class FragmentsStackActivity extends BaseActivity {
public static final String TAG_BUNDLE = "bundle_tag";
protected final Bundle fragmentArgs = new Bundle();
protected Stack<Fragment> fragments = new Stack<>();
abstract protected void setupFragments();
public void setFragmentArguments(Fragment fragment, Bundle arguments){
if(!fragments.isEmpty() && fragments.peek()!=fragment){
fragment.setArguments(arguments);
}
}
public void setFragmentFromStack() {
if(!fragments.isEmpty()) {
Fragment fragment = fragments.peek();
final Fragment oldFragment = getSupportFragmentManager().findFragmentById(R.id.fragment_container);
if (oldFragment == null || oldFragment != fragment) {
getFragmentManager().popBackStack(null, FragmentManager.POP_BACK_STACK_INCLUSIVE);
final FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
//transaction.setCustomAnimations(R.anim.animator_left_right_in, R.anim.animator_left_right_in);
transaction.replace(R.id.fragment_container, fragment).commit();
}
}else {
finish();
}
}
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
//TODO need to save fragment stack
}
}
example of an activity that extends this class
public class LoginActivity extends FragmentsStackActivity{
private final MyFragment1 fragment1 = new MyFragment1();
private final MyFragment2 fragment2 = new MyFragment2();
private final User mUser = new User();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
setupFragments();
setFragmentFromStack();
}
#Override
protected void setupFragments() {
fragments.add(fragment2);
//fragment2.setNotifier(this); // I use notifiers listener but you can choose whatever convenient for you
Bundle fragmentArgs = new Bundle();
fragmentArgs.putBoolean(Constants.TAG_LOGIN, true);
fragmentArgs.putParcelable(User.TAG, mUser);
fragmentArgs.putInt(Constants.TYPE, getIntent().getIntExtra(Constants.TYPE, 0));
fragment2.setArguments(fragmentArgs);
//fragment1.setNotifier(this); // I use notifiers listener but you can choose whatever convenient for you
}
// this method teals with handling messages from fragments in order to provide navigation
// when some actions taken inside the fragment, you can implement your own version
public void onReceiveMessage(String tag, Bundle bundle) {
switch (tag) {
case MyFragment2.TAG_BACK:
case MyFragment1.TAG_BACK:
fragments.pop();
setFragmentFromStack();
break;
case MyFragment2.TAG_NEXT:
fragment1.setArguments(bundle);
fragments.add(fragment1);
setFragmentFromStack();
break;
case MyFragment1.TAG_NEXT:
goToWelcomeScreen(bundle);
finish();
break;
}
}
private void goToWelcomeScreen(Bundle bundle){
}
}

You can implement this with the help of the following code:
// transaction.replace(R.id.detailFragment, frag1);
Transaction.remove(null).add(frag1) // frag1 on view
// transaction.replace(R.id.detailFragment, frag2).addToBackStack(null);
Transaction.remove(frag1).add(frag2).addToBackStack(null) // frag2 on view
// transaction.replace(R.id.detailFragment, frag3);
Transaction.remove(frag2).add(frag3) // frag3 on view
And for better understanding, have a ook at the following snippet:
// Works with either the framework FragmentManager or the
// support package FragmentManager (getSupportFragmentManager).
getSupportFragmentManager().beginTransaction()
.add(detailFragment, "detail")
// Add this transaction to the back stack
.addToBackStack()
.commit();
getSupportFragmentManager().addOnBackStackChangedListener(
new FragmentManager.OnBackStackChangedListener() {
public void onBackStackChanged() {
// Update your UI here.
}
});
have a look here http://developer.android.com/training/implementing-navigation/temporal.html

How to maintain fragment state without backstack in tab?

I am trying to save fragment state in onSaveInstanceState but when i go back to fragment, it always reloaded again instead of starting from last state.
I looked into onCreateView and onActivityCreated and it always have onSaveInstanceState as null.
public void navigateFragment(String tag, Fragment fragment,
boolean shouldAdd) {
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction ft = manager.beginTransaction();
if (shouldAdd)
mStacks.get(tag).push(fragment); // push fragment on stack
ft.replace(android.R.id.tabcontent, fragment);
if (shouldAdd)
ft.addToBackStack(tag);
ft.commit();
}
As i am unable to use backstack because in tabs back stack is not useful. Any help would be highly appreciated.

In this case you have to manage fragments' states by yourself. I don't know exactly how your code works so the only thing I can do is to give you some hints.
The first thing you need to implement is saving fragment's state. Let's assume that all fragments have unique ids. In this case you need to create a map that will keep all the states:
private final Map<String, Fragment.SavedState> mFragmentStates = new HashMap<>();
private void saveFragmentState(String id, Fragment fragment) {
Fragment.SavedState fragmentState =
getSupportFragmentManager().saveFragmentInstanceState(fragment);
mFragmentStates.put(id, fragmentState);
}
You need to call this method for a fragment that you're going to remove. Then we need to restore fragment's state and that's how we can do it:
private void restoreFragmentState(String id, Fragment fragment) {
Fragment.SavedState fragmentState = mFragmentStates.remove(id);
if (fragmentState != null) {
fragment.setInitialSavedState(savedState);
}
}
This method you need to call before adding a fragment to a transaction.
The code provided should work fine but to make it work correctly on activity recreation we need to save and restore mFragmentStates properly:
private static final String KEY_FRAGMENT_STATES = "fragment_states";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
/* Your code ... */
if (savedInstanceState != null) {
Bundle fragmentStates =
savedInstanceState.getParcelable(KEY_FRAGMENT_STATES);
if (fragmentStates != null) {
for (String id : fragmentStates.keySet()) {
Fragment.SavedState fragmentState =
fragmentStates.getParcelable(id);
mFragmentStates.put(id, fragmentState);
}
}
}
}
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
/* Your code ... */
Bundle fragmentStates = new Bundle(mFragmentStates.size());
for (Map.Entry<String, Fragment.SavedState> entry : mFragmentStates.entrySet()) {
fragmentStates.put(entry.getKey(), entry.getValue());
}
outState.putParcelable(KEY_FRAGMENT_STATES, fragmentStates);
}
Also you can take a look at FragmentStatePagerAdapter class. It uses the same approach for managing states of ViewPager's fragments.
UPDATE: And so your code should end up looking something like this:
private Fragment mCurrentFragment;
public void navigateFragment(String tag, Fragment fragment,
boolean shouldAdd) {
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
if (shouldAdd) {
mStacks.get(tag).push(fragment); // push fragment on stack
}
if (mCurrentFragment != null) {
saveFragmentState(mCurrentFragment.getClass().getName(), mCurrentFragment);
}
mCurrentFragment = fragment;
restoreFragmentState(fragment.getClass().getName(), fragment);
transaction.replace(android.R.id.tabcontent, fragment);
if (shouldAdd) {
// You shouldn't use back-stack when managing fragment states by yourself.
transaction.addToBackStack(tag);
}
transaction.commit();
}
In this example I use fragment's class name as an id so all the fragment must have different classes. But you can use any other unique value as an id. And another important thing I have to mention is that you shouldn't use back-stack when managing fragment states by yourself. Back-stack performs similar state management and you will likely have conflicts.

I think you should use the idea of Shared Preferences, this is faster than using local files or database, and definitely easier to code. A good Android webpage # Storage Options. I'll put some sample code from the webpage and change a few to fit your needs.
First, get the data saved from preferences in onCreate() override method:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
boolean silent = settings.getBoolean("silentMode", false);
...
}
Next let's save data before the fragment stops or exits, for various reasons. Achieve this by override onDetach method, the webpage override onStop() instead.
#Override
public void onDetach() {
super.onDetach();
...
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("silentMode", mSilentMode);
// Commit the edits!
editor.commit();
}
Good luck, have fun!

You are doing replace fragment, thats why fragment is getting destroyed. You can try below. Here i am doing two things in single FragmentTransaction, i am adding a new fragment & hiding the existing fragment.
Lets say we are adding fragment B on top of Fragment A
FragmentTransaction ft = fragmentManager.beginTransaction();
ft.add(android.R.id.tabcontent, fragmentB, tagFragmentB)
.hide(fragmentManager.findFragmentByTag(tagFragmentA))
.addToBackStack(tag)
.commit();
Once you do back press, it will remove the fragment B & show the fragment A with same state(before you added fragment B)
Please note here tagFragmentA & tagFragmentB are tags with which fragments A & B are added respectively

clearBackStackEntry();
rl.setVisibility(View.GONE);
getSupportFragmentManager().beginTransaction()
.replace(FRAGMENT_CONTAINER, new HomeScreen())
.addToBackStack(null).commit();
private void clearBackStackEntry() {
int count = getSupportFragmentManager().getBackStackEntryCount();
if (count > 0) {
getSupportFragmentManager().popBackStack(null,
FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
}
TRY THIS AND One more for fragment also try this: but use support.v4.app.Fragment, May be it will help you
Fragment fr = new main();
android.support.v4.app.FragmentTransaction fragmentTransaction = getFragmentManager()
.beginTransaction();
fragmentTransaction.replace(R.id.fragment_place, fr);
fragmentTransaction.commit();
// getActivity().finish();

declare
setRetainInstance(true)
In your fragment onCreate(). to recreate previous state
And link will helpful for understanding for how setRetainInstance work.
Understanding Fragment's setRetainInstance(boolean)
Why use Fragment#setRetainInstance(boolean)?
Thanks :)

it is very simple to handle these things. I can give you the sample to handle the back press on Fr agents which we added.
I have declared a fragment stack and push all the fragments in it like;
public static Stack<Fragment> fragmentStack;
make a method like this:
public static void replaceFragementsClick(Fragment fragementObj, Bundle bundleObj, String title){
try {
FragmentManager fragmentManager = ((FragmentActivity) mContext).getSupportFragmentManager();
if (fragementObj != null) {
fragementObj.setArguments(bundleObj);
fragmentManager.beginTransaction().replace(R.id.frame_container, fragementObj).commit();
}
DashBoardActivity.fragmentStack.push(fragementObj);
} catch (Exception e) {
e.printStackTrace();
}
}
Try this one also:
public static void replaceFragementsClickBack(Fragment fragementObj, Bundle bundleObj, String title){
try {
FragmentManager fragmentManager = ((FragmentActivity) mContext).getSupportFragmentManager();
if (fragementObj != null) {
fragementObj.setArguments(bundleObj);
fragmentManager.beginTransaction().replace(R.id.frame_container, fragementObj).commit();
DashBoardActivity.fragmentStack.pop();
}
} catch (Exception e) {
e.printStackTrace();
}
}
In the base activity where you have added, override the backpressed like:
#Override
public void onBackPressed() {
/**
* Do Current Fragment Pop
* */
fragmentStack.pop();
if(fragmentStack.size() >0){
Bundle bunldeObj = new Bundle();
//******Exit from Current Fragment
Fragment fragment = fragmentStack.pop();
// fragmentStack.push(fragment);
if(fragment instanceof PhotosFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Photos");
}else if(fragment instanceof PhotoDetatilFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Photos");
}else if(fragment instanceof PhotoFullViewFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Photos");
}else if(fragment instanceof HomeFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Home");
}else if(fragment instanceof VideosFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Videos");
}else if(fragment instanceof VideoDetailFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Videos");
}else if(fragment instanceof VideoViewFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Videos");
}else if(fragment instanceof MusicFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Music");
}else if(fragment instanceof MusicListFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Music");
}else if(fragment instanceof InstallAppsFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Apps");
}else if(fragment instanceof MessageFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Messages");
}else if(fragment instanceof MessageDetailFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Messages");
}else if(fragment instanceof LocateDeviceFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Locate Device");
}else if(fragment instanceof FilesFragmentBottomBar){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Files");
}else if(fragment instanceof AppsFragment){
bunldeObj.putString("position", "4");
replaceFragementsClick(fragment,bunldeObj,"Apps");
}else {
super.onBackPressed();
Intent intent = new Intent(DashBoardActivity.this,ConnectDeviceActivity.class);
startActivity(intent);
finish();
}
}

I am not clear of way kind of vie you are using for implementing Tabs.
I guessed from,
ft.replace(android.R.id.tabcontent, fragment);
that you might have implemented FragmentTabHost.
write a customFragmentTabhost and override
#Override
public void onTabChanged(String tabId) {
FragmentTransaction t = getSupportFragmentManager().beginTransaction();
if (tabId.equals(“Tab1”)) {
TabFragment1 fragment1 = null;
if (getSupportFragmentManager().findFragmentByTag(“Tab1”) == null) {
fragment1 = new TabFragment1();
} else {
fragment1 = (TabFragment1) getSupportFragmentManager().findFragmentByTag("Tab1");
}
t.replace(R.id.realContent, fragment1, "Tab1").addToBackStack(null).commit();
}
}
UPDATE:
Ensure Activity is not recreated on orientation, If so setRetainInstance(true), so that even if activity is recreated on orientation change, the fragments will be retained.
Do give id for any views in the fragment. It is important for Android system to maintain state.

Saving Fragment State/Data from Fragment to Fragment

I'm trying to figure out how to save user inputted data on a fragment if they leave it and come back. I have one Activity that several Fragments work off of. All the examples I find are saving the state when leaving the Fragment and Activity. I'm never leaving the Activity; therefore onSaveInstanceState within the Fragment is never called. onPause is called, but I'm unable to figure out how to save the state within there.
This app displays a list of tickets. When the user taps a ticket, it grabs preliminary information from the local DB for read only fields and allows the user to input the ticket information before submitting. I'm trying to allow a user to tap on a ticket, enter data, leave and come back to that ticket without losing information entered.
Out of all the examples I've studied on this, it seems to me I can use Fragmenttransaction to save the Fragment's ID. Below is the main Activity that all fragments are attached to:
public class Activity_Main extends Activity
implements Fragment_OpenTickets.INT_OnOpenTicketSelectedListener,
Fragment_SubTickets.INT_OnSubTicketSelectedListener,
Fragment_Ticket.INT_SubmitNewTicket {
DBController dbc;
Fragment fr;
boolean gps_enabled = false;
boolean network_enabled = false;
HashMap<String, String> addInfo;
RadioButton btn_radio_open;
RadioButton btn_radio_submitted;
RadioButton btn_radio_settings;
String ticketDate, ticketTime;
int m, d, y, hr, min;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn_radio_open = (RadioButton)findViewById(R.id.radio_open);
btn_radio_submitted = (RadioButton)findViewById(R.id.radio_submitted);
btn_radio_settings = (RadioButton)findViewById(R.id.radio_settings);
dbc = new DBController(this);
if (dbc.checkCredentials() != null) {
fr = new Fragment_OpenTickets();
} else {
fr = new Fragment_Settings();
btn_radio_open.setChecked(false);
btn_radio_submitted.setChecked(false);
btn_radio_settings.setChecked(true);
}
FragmentManager fm = getFragmentManager();
final FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.fragment_place, fr);
ft.addToBackStack(null); // For back button action.
ft.commit();
// Start scheduler service.
this.startService(new Intent(this, Service_Send.class));
// Start GPS service.
startGPS();
}
/**
* Top menu buttons.
*/
public void selectFrag(View view) {
FragmentTransaction ft = getFragmentManager().beginTransaction();
switch (view.getId()) {
case R.id.radio_open:
//fr = new Fragment_OpenTickets();
ft.replace(R.id.fragment_place, new Fragment_OpenTickets());
ft.addToBackStack(null);
btn_radio_submitted.setChecked(false);
btn_radio_settings.setChecked(false);
ft.commit();
break;
case R.id.radio_submitted:
//fr = new Fragment_SubTickets();
ft.replace(R.id.fragment_place, new Fragment_SubTickets());
ft.addToBackStack(null);
btn_radio_open.setChecked(false);
btn_radio_settings.setChecked(false);
ft.commit();
break;
case R.id.radio_settings:
//fr = new Fragment_Settings();
ft.replace(R.id.fragment_place, new Fragment_Settings());
ft.addToBackStack(null);
btn_radio_open.setChecked(false);
btn_radio_submitted.setChecked(false);
ft.commit();
break;
}
}
/**
* Open ticket selection action.
*/
public void onOpenTicketSelected(HashMap position) {
// Create fragment and give it an argument for the selected ticket.
fr = new Fragment_Ticket();
Bundle args = new Bundle();
args.putSerializable("HashMap", position);
fr.setArguments(args);
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.fragment_place, fr);
ft.addToBackStack(null); // For back button action.
ft.commit();
}
/**
* Submitted ticket selection action.
*/
public void onSubTicketSelected(HashMap position) {
// Create fragment and give it an argument for the selected ticket.
fr = new Fragment_SubTicket();
Bundle args = new Bundle();
args.putSerializable("HashMap", position);
fr.setArguments(args);
FragmentManager fm = getFragmentManager();
FragmentTransaction fragmentTransaction = fm.beginTransaction();
fragmentTransaction.replace(R.id.fragment_place, fr);
fragmentTransaction.addToBackStack(null); // For back button action.
fragmentTransaction.commit();
}
Any help will be very appreciated. If I need to post more code then please let me know. Thank you!

I think you should store ticket info in your Activity when users leave the fragment and get the info back and display it when you come back.
In Activity_Main class, you create 2 methods:
public void saveTicketInfo(TicketInfo info) {
// save info here
}
And:
public TicketInfo getTicketInfo() {
// get info here
}
In your fragment:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
...
// get ticket info and display it
Activity_Main mainActivity = (Activity_Main)getActivity();
TicketInfo info = mainActivity.getTicketInfo();
if (info != null) {
// handle display info here
}
...
}
#Override
public void onDestroyView() {
TicketInfo info = new TicketInfo();
// get info from view and store in the object
Activity_Main mainActivity = (Activity_Main)getActivity();
mainActivity.saveTicketInfo(info)
super.onDestroyView();
}

I posted a lengthy detailed answer on SO # Passing data between fragments contained in an activity. Search for my answer on it. This is a safe way to pass data from Fragment to Activity. And then you can easily pass that data from Activity to the Fragment's constructor or public method.

Android rotation: Why fragment not restored by TAG?

I have an activity called MainActivity with a fragment inside called 'HomeFragment'. I want to restore fragment after screen rotation, however something seems missing.
I followed below process:
save fragment by using getSupportFragmentManager().putFragment(...) during onSaveInstanceState
try to restore fragment by fragmentManager.findFragmentByTag during onCreate (after checking that bundle is not null)
However findFragmentByTag returns null.
Here is code snippets inside MainActivity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Set up the action bar to show a dropdown list.
final ActionBar actionBar = getSupportActionBar();
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST);
setupNavigationSpinner(actionBar);
FragmentManager fragmentManager = getSupportFragmentManager();
if (savedInstanceState != null) {
if (fragmentManager.findFragmentByTag("frag") != null) {
// findFragmentByTag always return null
homeFragment = (HomeFragment) fragmentManager
.findFragmentByTag(HomeFragment.ARG_ITEM_ID);
contentFragment = homeFragment;
}else{
homeFragment = new HomeFragment();
switchContent(homeFragment, HomeFragment.ARG_ITEM_ID);
}
} else {
homeFragment = new HomeFragment();
switchContent(homeFragment, HomeFragment.ARG_ITEM_ID);
}
}
#Override
public void onSaveInstanceState(Bundle outState) {
getSupportFragmentManager().putFragment(outState, "frag",homeFragment );
}
public void switchContent(Fragment fragment, String tag) {
FragmentManager fragmentManager = getSupportFragmentManager();
while (fragmentManager.popBackStackImmediate())
;
if (fragment != null) {
FragmentTransaction transaction = fragmentManager
.beginTransaction();
transaction.replace(R.id.content_frame, fragment, tag);
// Only ArticlDetailFragment is added to the back stack.
if (!(fragment instanceof Fragment)) {
transaction.addToBackStack(tag);
}
transaction.commit();
contentFragment = fragment;
}
}

There is no reason to call
getSupportFragmentManager().putFragment(outState, "frag",homeFragment );
A Fragment state will automatically be restored. The problem is that you're not calling the super of your onSaveInstanceState. It should simply look like this:
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
}
Also, you're setting the tag as HomeFragment.ARG_ITEM_ID then looking for "frag". Does HomeFragment.ARG_ITEM_ID == "frag"?

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