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how to restore last opened fragment inside an activity after getting back from another actvivty

I'm using multiple fragments inside an activity like this flow: Fragment A has a list on it's item click Fragment B opens and it also has a list opens Fragment C which has a list Open another Activity , The problem is when I go back from the other Activity I found Fragment A is opened, How I restore the last Fragment C when go back from the other activity?
here is the code of replacing Fragment inside my activity
protected void showFragment(Fragment fragment) {
String TAG = fragment.getClass().getSimpleName();
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.container_home, fragment, TAG);
fragmentTransaction.addToBackStack(TAG);
fragmentTransaction.commit();
}

replace removes the existing fragment and adds a new fragment. This means when you press back button the fragment that got replaced will be created with its onCreateView being invoked. Whereas add retains the existing fragments and adds a new fragment that means existing fragment will be active.
Use add instead of replace
fragmentTransaction.add(R.id.container_home, fragment, TAG);
I had the same issue solved using the above code.

You can use
fragmentTransaction.addToBackStack(null);
instead of,
fragmentTransaction.addToBackStack(TAG);
Hope Your problem will solve.

back button issue in working with fragment in android

I am working on android app and use fragment for displaying user interface.
I am different fragment,i have two problem in app-
1. I am facing problem when user navigate from one fragment to another then multiple instance of same fragment is added in backstack.
Suppose user move from fragment1 to fragment2 then fragment3 and again move to fragment2 and thenpress back button then from backstack fragment3 is load and then fragment2 and then fragment1.so i just want to add a fragment one only in backstack.
I am creating only one instance of a fragment bu using my custom method for each fragment like-
public static Fragment getInstance(FragmentManager f){
if(mFragment==null){
mFragment = new HomeFragment();
}
fm = f;
return mFragment;
}
so each time when a fragment is replaced with a previous instance of same fragment.
2 after navigate to different screens when user presses virtual android mobile home button and app goes to sleep and after few hours if user again opens app then app force close.
Thanks in advance

Android Fragment Unable to go back

I have an app that uses fragments with tabs/viewpager
[Tab 1][Tab 2][Tab 3]
Tab2 has a ListView and in the onClick method of the ListView I am showing a detail view with the following code
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
NextFragment nextFragment = new NextFragment();
transaction.replace(R.id.container, nextFragment);
transaction.addToBackStack(null);
transaction.commit();
The issue is that in the NextFragment when I use the hardware back button the whole app closes?

I'm not sure why it doesn't let you return when back is pressed, but what I've done in my application is the following:
I have overriden the onBackPressed action and created a check that once it is pressed and the user is in the fragment that he wants to return from, just create another fragment transaction to the previous fragment.
I have done so because I needed to update the previous fragment, but I'm sure there is a better way to solve your problem.

Why is Fragment.addToBackStack() causing the Back button to do nothing?

Activity 1 is visible. Press a button, and Activity 2 opens.
Activity 2 adds fragment A to itself (and back stack) and it displays fine
Pressing a button within the fragment transitions to another fragment, B
Press Back. Nothing happens. Huh? The Back press is seemingly absorbed and not acted upon, the display remains the same.
Press Back a second time, it reverts to the Activity 1, as expected.
Why is my fragment not being shown in step 4? I've added the fragment to the back stack, so why (when the Back button seems aware of its existence) does it not show the fragment?
Here's the code I'm using in Activity 2 to open Fragment A.
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.act_profile_edit);
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.setCustomAnimations(android.R.anim.slide_in_left, android.R.anim.slide_out_right);
transaction.addToBackStack(null);
transaction.add(android.R.id.content, new MyFragment());
transaction.commit();
}
And here's the code to open Fragment B
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.setCustomAnimations(android.R.anim.slide_in_left, android.R.anim.slide_out_right);
transaction.add(android.R.id.content, new MyOtherFragment());
transaction.commit();

Have you tried transaction.replace(...) instead of transaction.add(...)? That should work. I'm guessing because if you're just adding a fragment over another, it doesn't see transaction as wanting to go back fro Fragment A.
EDIT
The actual answer for the question is below in the comments: addToBackStack() should be used on the fragment which is replacing, not the one being replaced.

Back key to pop the Fragment shows overlapping fragments

I created a sample app to test this overlapping issue.
I have a fragment type, Fragment1, and I create a new instance of Fragment1 and add it to a FrameLayout in my activity at runtime. I add the fragment with the help of a few buttons.
Note: I have given each new instance of Fragment1 a different number(#1, #2, #3, etc.) to display on the UI to help me figure out which fragment I am viewing.
So.. here is what I do:
Click on Button 3, create new instance of Fragment1 and add it to Frame1.
Click on Button 4, create new instance of Fragment1 and add it to Frame1 and add it to the fragment backstack.
Repeat 1 and 2.
Repeat 1 and 2.
Now, I have fragments in this order: 1(#1),2(#2),1(#3),2(#4),1(#5),2(#6).
I press the back key when viewing fragment #6.
Back key press, UI displays (#5).
Back key press, UI displays (#3 AND #5),
Back key press, UI displays (#1, #3, AND #5)
It seems fragments are getting displayed ON TOP of each other.
WHY? Is there an overlapping issue? How can I clear out this overlapping issue. I thought this would be an issue on the compatibility library... but it is also on 3.0.
Code for adding fragments:
public int doFragmentChange(int cont1, Fragment frag1, String tag1, int cont2, Fragment frag2, String tag2,
boolean addToStack, String stackTag) {
FragmentManager fm = getFragmentManager();// getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
if (frag1 != null) {
ft.replace(cont1, frag1, tag1);
}
if (frag2 != null) {
ft.replace(cont2, frag2, tag2);
}
// add fragment to stack
if (addToStack)
ft.addToBackStack(stackTag);
return ft.commit();
}

If you perform two add calls one after the other (two commit calls) then yes the fragments will appear overlaid, one on top of the other effectively.
So (for new example) if say you replace frag1 with frag2 and then frag3 with frag4 in the same frame with no backstack transaction then I would expect frag2 and frag4 to be overlaid.
Furtheremore there is also a potential issue in your chaining of replace. You should call a separate commit for each. See Android — Replace Fragment Back Stack With New Stack?.

Just override the onBackPress() or onKeyUp and remove the top fragment.