Develop Reference

Add only one instance of fragment into backstack

I have implemented fragments in my application. Here my code for swiching fragment in fragment_container.
private void switchFragment(Fragment fragment, boolean isAddToBackStack, String tag)
{
android.support.v4.app.FragmentManager fm = getSupportFragmentManager();
android.support.v4.app.FragmentTransaction ft = fm.beginTransaction();
ft.replace(R.id.container, fragment, tag);
if (isAddToBackStack)
ft.addToBackStack(tag);
setCurrentTopFragment(Integer.parseInt(tag));
ft.commit();
}
I have 4 fragments A,B,C and D and for switching between this fragmnets I am using above method. I have A,C,B in my backstack. If again I switch to fragmnet A, my backstack is like A,C,B,A. What I actually want is If I swich to A again I want backstack sequence like this C,B,A. Means Remove old instance from backstack and add new to it.

First get the back-stacked Fragment by id which you need to remove:
Fragment fragment = getSupportFragmentManager().getFragment(new Bundle(), TAG_KEY)
or there are several methods getBackStackEntryCount(), getBackStackEntryAt. After getting the fragment which you need to remove. Remove it from the fragment back-stack.
FragmentManager manager = getActivity().getSupportFragmentManager();
FragmentTransaction trans = manager.beginTransaction();
trans.remove(fragment);
Then you can add a new fragment Done :)

Not able to switch between fragment properly

I have 2 fragment on one fragment activity. I have 2 fragments say new and pending but I am having problem while switching from one fragment to another while tapping of button. When I am on pending tab and then click on new tab then sometimes it shows two loader and then it still shows pending page. My both fragments are android.support.v4.app.Fragment. I am attaching screenshot of the problem while I am tapping on new tab and still showing pending tab with two loader.
code for switching between fragment
#Override
public void onClick(View v) {
if (v.equals(neww))
{
Fragment newpage = new NewPageActivity();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.framelay, newpage);
ft.commit();
}
else if(v.equals(pending))
{
Fragment pendingFragment = new PendingPage();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.framelay, pendingFragment);
ft.commit();
}
}
now screenshot of problem

Try this:
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.replace(R.id.framelay, fragment);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
ft.commit();

Issue in Fragments in android

When I click on the back icon in the layout then it goes to previous fragment but it doesn't go to the fragment it was killed. what is the solution for this?
I'm using finish() and backstack but it not works for me
back.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
android.support.v4.app.Fragment onlineFragments = new OnlineFragments();
android.support.v4.app.FragmentManager fragmentManagerprofile = getActivity().getSupportFragmentManager();
android.support.v4.app.FragmentTransaction fragmentprofileTransaction = fragmentManagerprofile.beginTransaction();
fragmentprofileTransaction.replace(R.id.background_fragment, onlineFragments);
fragmentprofileTransaction.commit();
}
});
Fragment A
case R.id.recharge:
HomeActvity.toolbar.setVisibility(View.GONE);
android.support.v4.app.Fragment Recharge = new Prepaid_recharge();
android.support.v4.app.FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
android.support.v4.app.FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.containerView, Recharge);
fragmentTransaction.commit();
break;

Whenever your making Transactions between fragments and you want to navigate back to the previous fragment(s) (Back Button), in the transaction, you must add this transaction to the backStack before committing:
Android docs:
"Before you call commit(), however, you might want to call addToBackStack(), in order to add the transaction to a back stack of fragment transactions. This back stack is managed by the activity and allows the user to return to the previous fragment state, by pressing the Back button."
https://developer.android.com/guide/components/fragments.html#Transactions
// Create new fragment and transaction
Fragment newFragment = new ExampleFragment();
FragmentTransaction transaction = getFragmentManager().beginTransaction();
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();

I use this code to add and remove the fragment. In case I do not need that fragment to be in the back stack I send the boolean value as false. Doing this when pressing back button from toolbar It open the correct activity
public static void changeFragment (MyActivity activity, Fragment fragment, int fragmentContainer, boolean addToBackStack){
FragmentManager fragmentManager = activity.getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(fragmentContainer, fragment);
/*here we keep track of fragments and avoiding last blank fragment by passing true*/
if(addToBackStack){
fragmentTransaction.addToBackStack(null);
}
fragmentTransaction.commit();
}

android fragment transition animation

I have one dialog with list of item.
on click of each item i push one fragment.
I want that fragment to load with animation.
I knew how to do animation from fragment to fragment
but help me to apply animation when i have only one fragments
This is what i already tried, this helps to apply transition between two fragments.
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.setCustomAnimations(R.anim.slide_in_left, R.anim.slide_out_right);
DetailsFragment newFragment = DetailsFragment.newInstance();
ft.replace(R.id.details_fragment_container, newFragment, "detailFragment");
// Start the animated transition.
ft.commit();

Required common method for each item click where different fragment push.
You have to put common method in code.
Method code
public void pushFragments
(Fragment fragment, boolean shouldAnimate, boolean shouldAddinbackstack, String tag) {
FragmentManager manager = getActivity().getSupportFragmentManager();
FragmentTransaction ft = manager.beginTransaction();
ft.replace(R.id.realtabcontent, fragment, tag);
if (shouldAddinbackstack) {
//add fragment in backstack entry
ft.addToBackStack(tag);
}
if (shouldAnimate) {
//fragment animated
ft.setCustomAnimations(R.anim.slide_in_left, R.anim.slide_out_right);
}
ft.commit();
}
use method on item click e.g
DetailsFragment newFragment = DetailsFragment.newInstance();
pushFragments(newFragment, true, true, "detailsFragment");

How to show second fragment from first fragment with in a single activity

I am developing a simple android app only for tablets and using android 4.0. My application have the main screen like as follow:
Oncreate() of Main Activity I am adding Fragment A in the main.xml using following code:
FragmentTransaction ft = getFragmentManager().beginTransaction();
Fragment imageFragment = new ImageFragment();
ft.replace(R.id.fragment_container, imageFragment);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
ft.addToBackStack(null);
ft.commit();
This fragment A just have only a Image view which is clickable. Now I want that when user click on Image view then another fragment (Fragment B) should call and it replace the image view. The Fragment B have a VideoView which play the video.
So My second screen should be like as follow:
My problem is I am not gettting "How to call second fragment from the first one with in main screen activity?"
I can use different activities but I do not want to do so and just want to run this using fragments.
Please guide me.

This is the simplest way:
1) Inside YourActivitycreate a method:
public void goToSecondFragment(){}
FragmentTransaction ft = getFragmentManager().beginTransaction();
Fragment secondFragment = new SecondFragment();
ft.replace(R.id.fragment_container, secondFragment);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
ft.addToBackStack(null);
ft.commit();
}
2) In your first fragment, when you want to replace it, call:
YourActivity activity = (YourActivity) getActivity();
activity.goToSecondFragment();

You can do the same using below:
Adding a fragment with maintaining a back stack
FragmentManager supportFragmentManager = getSupportFragmentManager();
supportFragmentManager.addOnBackStackChangedListener(new OnBackStackChangedListener() {
#Override
public void onBackStackChanged() {
}
});
FragmentTransaction fragmentTransaction = supportFragmentManager.beginTransaction();
fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
fragmentTransaction.addToBackStack("fragmentTag");
fragmentTransaction.replace(R.id.slate, fragment, "fragmentTag");
fragmentTransaction.commit();
And Replacing a fragment
FragmentManager supportFragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = supportFragmentManager.beginTransaction();
fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
fragmentTransaction.replace(R.id.slate, fragment, "fragmentTag");
fragmentTransaction.commit();
Should work for you.