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Fragment not showing previous data when coming from another fragment

In my android activity I am using multiple fragments, I am successfully switching these fragments according to my requirement but problem is that when I am switching Fragment 1 to Fragment 2 and back from Fragment 2 to Fragment 1, Fragment 1 not showing previous data Fragment 1 start from stretch, but I want to show previous data same as I was selected.
Here is my code for go Fragment 1 (fragment_search_customerProfile) to Fragment 2 (fragment_CustomerInfo):
FragmentManager manager = getActivity().getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.replace(R.id.filterFram, new fragment_Search());
FrameLayout layout = (FrameLayout) rootView.findViewById(R.id.cpFrame);
layout.removeAllViewsInLayout();
transaction.remove(new fragment_search_customerProfile()).commit();
Here is my code for back Fragment 1 (fragment_search_customerProfile) fromFragment 2 (fragment_CustomerInfo):
FragmentManager manager = getActivity().getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
Log.d("fragment_Search", fromSearch + "");
transaction.replace(R.id.custIndoFram, new fragment_search_customerProfile());
FrameLayout layout = (FrameLayout) rootView.findViewById(R.id.custIndoFram);
layout.removeAllViewsInLayout();
transaction.remove(new fragment_CustomerInfo()).commit();
Can anyone explain me how can I stay save my fragment data?

Instead of transaction.replace(R.id.filterFram, new fragment_Search());
you can use transaction.add to add fragment while having the data of first one
transaction.add(R.id.filterFram, new fragment_Search());
transaction.addToBackStack(null);
From fragment two you can use .show instead of replace to show the first fragment
and hide fragment two from the first one. transaction.show(getSupportFragmentManager().findFragmentByTag("firstFragmentTag")).commit();

You can simple keep the instances of the fragments, so in your Activity you would have fields like that.
private Fragment fragment1;
private Fragment fragment2;
And now you can use the sexy replace() option,
To add Fragment1
if (fragment1 == null) {
fragment1 = new fragment_Search();
}
FragmentManager manager = getActivity().getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.replace(R.id.filterFram, fragment1);
and same for Fragment2
And you can hold the state of the fragment (data it retrieves) in the Fragment itself, and in your onViewCreated() you check, if the state is not null, you update the view immediately.
class Fragment1 extends Fragment {
private State state;
public void onViewCreated(View v) {
if (state != null) {
// Update UI here
}
}
}
UPDATE
Using your own code
private Fragment fragment1; // This is a field outside of below method
if (fragment1 == null) {
fragment1 = new fragment_Search();
}
FragmentManager manager = getChildFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.replace(R.id.filterFram, fragment1).commit();
FrameLayout layout = (FrameLayout) rootView.findViewById(R.id.cpFrame);
layout.removeAllViewsInLayout();
Going to fragment2 should be the same, and this code is used to go to Fragment1 and Fragment2, doesn't matter if you are going back or first time.

You have to add fragment instead of remove or replace

Fragments overlapping while using replace() [duplicate]

I have a fragment inside a group activity and I want to replace it with another fragment:
FragmentTransaction ft = getActivity().getFragmentManager().beginTransaction();
SectionDescriptionFragment bdf = new SectionDescriptionFragment();
ft.replace(R.id.book_description_fragment, bdf);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
ft.addToBackStack(null);
ft.commit();
It works fine when it is done as a seperate project without using activity group, every thing works fine in log cat as control goes inside getview(), but no view is visible, not even any exception arises, I want the book detail fragment to be replaced by section detail fragment.
Xml of book detail fragment has id book_description_fragment and xml for section description fragment has id section_description_fragment.
The above code is in onClick method of an item, I want that when user taps on an item in horizontal scroll view, then the fragment changes.

Fragments that are hard coded in XML, cannot be replaced. If you need to replace a fragment with another, you should have added them dynamically, first of all.
Note: R.id.fragment_container is a layout or container of your choice in the activity you are bringing the fragment to.
// Create new fragment and transaction
Fragment newFragment = new ExampleFragment();
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack if needed
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();

Please see this Question
You can only replace a "dynamically added fragment".
So, if you want to add a dynamic fragment, see this example.

I've made a gist with THE perfect method to manage fragment replacement and lifecycle.
It only replace the current fragment by a new one, if it's not the same and if it's not in backstack (in this case it will pop it).
It contain several option as if you want the fragment to be saved in backstack.
=> See Gist here
Using this and a single Activity, you may want to add this to your activity:
#Override
public void onBackPressed() {
int fragments = getSupportFragmentManager().getBackStackEntryCount();
if (fragments == 1) {
finish();
return;
}
super.onBackPressed();
}

Use the below code in android.support.v4
FragmentTransaction ft1 = getFragmentManager().beginTransaction();
WebViewFragment w1 = new WebViewFragment();
w1.init(linkData.getLink());
ft1.addToBackStack(linkData.getName());
ft1.replace(R.id.listFragment, w1);
ft1.commit();

Use ViewPager. It's work for me.
final ViewPager viewPager = (ViewPager) getActivity().findViewById(R.id.vp_pager);
button = (Button)result.findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
viewPager.setCurrentItem(1);
}
});

hope you are doing well.when I started work with Android Fragments then I was also having the same problem then I read about
1- How to switch fragment with other.
2- How to add fragment if Fragment container does not have any fragment.
then after some R&D, I created a function which helps me in many Projects till now and I am still using this simple function.
public void switchFragment(BaseFragment baseFragment) {
try {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.setCustomAnimations(android.R.anim.slide_in_left, android.R.anim.slide_out_right);
if (getSupportFragmentManager().findFragmentById(R.id.home_frame) == null) {
ft.add(R.id.home_frame, baseFragment);
} else {
ft.replace(R.id.home_frame, baseFragment);
}
ft.addToBackStack(null);
ft.commit();
} catch (Exception e) {
e.printStackTrace();
}
}
enjoy your code time :)

you can use simple code its work for transaction
Fragment newFragment = new MainCategoryFragment();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.content_frame_NavButtom, newFragment);
ft.commit();

You Can Use This code
((AppCompatActivity) getActivity()).getSupportFragmentManager().beginTransaction().replace(R.id.YourFrameLayout, new YourFragment()).commit();
or You Can This Use Code
YourFragment fragments=(YourFragment) getSupportFragmentManager().findFragmentById(R.id.FrameLayout);
if (fragments==null) {
getSupportFragmentManager().beginTransaction().replace(R.id.FrameLayout, new Fragment_News()).commit();
}

I change fragment dynamically in single line code
It is work in any SDK version and androidx
I use navigation as BottomNavigationView
BottomNavigationView btn_nav;
FragmentFirst fragmentFirst;
FragmentSecond fragmentSecond;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_search);
fragmentFirst = new FragmentFirst();
fragmentSecond = new FragmentSecond ();
changeFragment(fragmentFirst); // at first time load the fragmentFirst
btn_nav = findViewById(R.id.bottomNav);
btn_nav.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem menuItem) {
switch(menuItem.getItemId()){
case R.id.menu_first_frag:
changeFragment(fragmentFirst); // change fragmentFirst
break;
case R.id.menu_second_frag:
changeFragment(fragmentSecond); // change fragmentSecond
break;
default:
Toast.makeText(SearchActivity.this, "Click on wrong bottom SORRY!", Toast.LENGTH_SHORT).show();
}
return true;
}
});
}
public void changeFragment(Fragment fragment) {
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_layout_changer, fragment).commit();
}

In kotlin you can do:
// instantiate the new fragment
val fragment: Fragment = ExampleFragment()
val transaction = supportFragmentManager.beginTransaction()
transaction.replace(R.id.book_description_fragment, fragment)
transaction.addToBackStack("transaction_name")
// Commit the transaction
transaction.commit()

This will work if you're trying to change the fragment from another fragment.
Objects.requireNonNull(getActivity()).getSupportFragmentManager()
.beginTransaction()
.replace(R.id.home_fragment_container,new NewFragment())
NOTE As stated in the above answers, You need to have dynamic fragments.

You can use fragment-ktx
// If you are in fragmet
childFragmentManager.beginTransaction()
// or if you are in activiry
supportFragmentManager.beginTransaction()
// Create and commit a new transaction
supportFragmentManager.commit {
setReorderingAllowed(true)
// Replace whatever is in the fragment_container view with this fragment
replace<ExampleFragment>(R.id.fragment_container)
}

To replace a fragment with another one do this, Note that R.id.fragment comes from the id that you give to the first tag of the fragment in the XML.
barAudioPlaying.setOnClickListener(view -> {
getActivity().getSupportFragmentManager()
.beginTransaction()
.replace(R.id.fragment,new HomeFragment())
.commit();

How to reuse existing fragment from FragmentManager instead of re-creating them again?

I am using NavigationDrawer in my application and each menu item in drawer is a fragment.Whenever user chooses a menu item I replace the current fragment in the main container with the requested one but it recreates the fragment every-time, so i updated my code to reuse the existing fragments instead of creating them again and again as content of fragments remain same. My updated code to show fragment is :
public void showTabFragment() {
TabFragment Tf = (TabFragment) mFragmentManager.findFragmentByTag(Constants.TAB_FRAGMENT);
mFragmentTransaction = mFragmentManager.beginTransaction();
if (Tf != null) {
mFragmentTransaction.replace(R.id.containerView, Tf, Constants.TAB_FRAGMENT);
} else {
mFragmentTransaction.replace(R.id.containerView, new TabFragment(), Constants.TAB_FRAGMENT);
}
mFragmentTransaction.commit();
}
In above code I am trying to get fragments by Tag but it always returns null and executes the else case(new fragment).Could someone please guide me what am I doing wrong in my code?

I guess the code you've shown is for one of your menu fragment? If that's the case, what is probably happening is every time you open a menu item, the container is replaced with the new fragment(say, Fragment B) with its new tag(say, TAG 'B'). So, when you try to open the previous fragment(say, Fragment A) using it's tag(TAG 'A'), it won't be there, because that's what you replaced.
One possible solution is to hold references to the fragment as they are created, in, say a hashmap, and reuse them instead.
private HashMap<String, Fragment> menuFragments = new HashMap<>();
public void showMenu(String fragmentID)
{
MenuFragment fragment = menuFragments.get(fragmentID);
if(fragment == null)
{
fragment = new MenuFragment(); //Create the respective menu fragment based on the ID.
menuFragments.put(fragmentID, fragment);
}
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.containerView, fragment, fragmentID);
transaction.commit();
}

How to update the content of a TextView in a fragment in navagation drawer in Android

I'am new to Android application developpement. I'am trying to create an application using navigation drawer. I created an apllication with the navigation drawer template with android studio. Then i changed it to redirect the user to a new fragment_layout each time he chooses a new item in the navigation menu. Now, my first fragment contains a listview, and onclick on one item of the list i am redirected to a detailfragment which contains a TextView.
When i tried to populate this TextView with details of the selected item i had a null pointer exception.After two days of research and trying to find out what is the problem i discovered that my visible fragment returns false when i call fragment.isInLayout().
Thanks for your help.
My code :
Creation of a new fragment :
VideoDetailFragment fragment = new VideoDetailFragment();
Bundle bundle = new Bundle();
bundle.putString("title", title)
fragment.setArguments(bundle);
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.replace(R.id.container, fragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
getFragmentManager().executePendingTransactions();
if (fragment.isInLayout()) {
fragment.replaceText("Lalala");}
And the method replaceText code is :
public void replaceText(String text){
textView.setText(text);
}
The problem is that the methode replaceText is not reached And when i remove the if statement a null pointer exception is raised saying that i can not write in the textView
EDIT: I think the problem is with transaction.replace(R.id.container,fragment);, maybe there is another alternative to replace a fragment_layout content. Because, i have the VideoDetailFragment displayed in the simulator and i can't change it's content, Also when i tired VideoDetailFragment fragment1 = (VideoDetailFragment)getFragmentManager().findFragmentById(R.id.container);
it gave me a cast exception.
Thanks a lot for your help, really need it :)

Try to do something like this:
Fragment fragment = new Fragment();
Bundle bundle = new Bundle();
bundle.putString(key, value);
fragment.setArguments(bundle);
Then in your second Fragment, retrieve the data (you could do it for example in onCreate()) with:
Bundle bundle = this.getArguments();
int myString = bundle.getString(key, ""); //the second parameter is a default value
Or show your code to see where do you get NullPointerException

YourFragment fragment = getSupportFragmentManager().findFragmentById(R.id.your_fragment);
if (fragment != null) {
fragment.yourUpdateDataMethod(youData);
}

How to save a viewpager content contained in a fragment?

I use a master/detail flow and in every fragment I have a viewpager containing some forms but the thing is when I click on some other links from the master list, the content of the viewpager is lost. How to save this content so everytime I click on the same choice I find my data.
My code :
#Override
public void onItemSelected(String id) {
if (mTwoPane) {
// In two-pane mode, show the detail view in this activity by
// adding or replacing the detail fragment using a
// fragment transaction.
if(id.contains("1"))
{
Bundle arguments = new Bundle();
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setRetainInstance(true);
fragment.setArguments(arguments);
getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment).commit();
}
else if(id.contains("2"))
{
Bundle arguments = new Bundle();
ItemDetailFragment2 fragment = new ItemDetailFragment2();
fragment.setRetainInstance(true);
fragment.setArguments(arguments);
getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment).commit();
}
} else {
// In single-pane mode, simply start the detail activity
// for the selected item ID.
Intent detailIntent = new Intent(this, ItemDetailActivity.class);
detailIntent.putExtra(ItemDetailFragment.ARG_ITEM_ID, id);
startActivity(detailIntent);
}
}
EDIT:
I tried to modify my code this way :
if (id.contains("1")) {
Fragment currFragment = fm.findFragmentByTag(lastTag);
ItemDetailFragment newFragment = (ItemDetailFragment) fm.findFragmentByTag("f"+1);
FragmentTransaction ft = fm.beginTransaction();
ft.hide(currFragment);
if(newFragment==null)
{lastTag="f"+1;
newFragment=new ItemDetailFragment();
ft
.replace(R.id.item_detail_container, newFragment);}
else {
ft.show(newFragment);
}
ft.commit();
}
But i got a NullPointerException at android.support.v4.app.BackStackRecord.run(BackStackrecord.java:656)

Try to call setRetainInstance(true) in your fragments onCreate()
As writed here, if you do not add the transaction to the back stack, then the fragment is destroyed when removed or replaced.
You can hide current fragment, instead replacing, then add new. Like that:
int currPage = 0;
public void goToPage(int num) {
FragmentManager fm = getSupportFragmentManager();
Fragment currFragment = fm.findFragmentByTag("f" + currPage);
Fragment newFragment = fm.findFragmentByTag("f" + num);
FragmentTransition ft = fm.beginTransaction();
ft.hide(currFragment);
if(newFragment == null) {
// First use. Create new instance for page.
newFragment = new MyFragment();
ft.add(R.id.item_detail_container, newFragment, "f" + num);
} else {
// Fragment for page already added. Just show it.
ft.show(newFragment);
}
ft.commit();
this.currPage = num;
}
And don't forget to specify tag for initial page fragment too.

You can implement the onPause() or onStop() methods of your fragments and save the data when that methods are called, which happens automatically when they are removed.
Or you could perhaps go with the savedInstanceState.

It's better to save in the arrayList. Onclick store the image id in the arrayList.