Develop Reference

Move from one Fragment inside Activity to another Fragment inside Activity

So I have Activity A with Fragment A.1, and I also have Activity B with Fragment B.1.
What I want to ask is, how do I move directly from Fragment A.1 to Fragment B.1?
I know to move from Fragment A.1 to Activity B, is by:
Intent i = new Intent (getActivity (), MainActivity.class);
startActivity (i);
getActivity ().finish();
But how to move straight to Fragment B.1?
Each Activity A and Activity B has a different <FrameLayout> for Fragment replacement
UPDATE 1.0
I've tried my own way and also the way #cewaphi answered with code like this,
In Activity A:
Intent i = new Intent(TransactionDone.this, MainActivity.class);
i.putExtra("immediatelyTransactionToFragment", true);
startActivity(i);
finishAffinity();
In Activity B:
boolean shouldTransitionToFragment = getIntent().getBooleanExtra("immediatelyTransationToFragment", true);
if (shouldTransitionToFragment) {
Fragment fragment = new Wallet();
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.mainFrameLayout, fragment);
transaction.commit();
Log.d("DEBUGGING REDIRECT", "Go to Fragment B.1");
}
The log "Go to Fragment B.1" was created but the transaction doesn't work

When using a single activity and e.g. using the navigation component is not an option.
Consider the following:
In your fragment A.1 when starting the activity store a Boolean
i.putExtra("immediatelyTransationToFragment", true);
In activity B
shouldTransitionToFragment = getIntent().getBooleanExtra("immediatelyTransationToFragment");
// after activity was created
if (shouldTransitionToFragment) {
// Execute the transition action as you would when pressing the button
}
Update 2020/09/07
You are trying to transition to a Fragment from your Activity like this:
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.mainFrameLayout, fragment);
transaction.commit();
The documentation states that you should first add the fragment to the activity:
ExampleFragment fragment = new ExampleFragment();
fragmentTransaction.add(R.id.fragment_container, fragment);
fragmentTransaction.commit();
Apparently your transition works when you click your button. Are you doing it the same?
But I assume at that time the activity has already been created.
Try once to add your fragment instead of replace. I don't know how your container is initialised but adding might be the operation you want, I refer to this good answer for clarification.
Also consider to perform to call this transaction after your activity was created.

Multiple Fragment To Single Actitvity

I don't know how to express this, but the idea was I have a Navigation Drawer that will call (Intent an Activity) and that Activity will automatically replace the content base from the NavigationView link click.
So from my MainActivity -> ReadActivity (Activity call other Activity) and replace the ReadActivity content with the topic click from the NavigationView .
This code I use for replacing:
LayeringViewer layeringViewer = new LayeringViewer();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.layer_frame_layout,layeringViewer);
ft.commit();
I know how to place a fragment. But how can I do this while calling other Activity? Passing the Fragments like Bundles.

if you want to change the content according to selection from drawer, then pass data on drawer close to activity and according to that replace fragments
Ex:
Fragment fragment = new SupportFragment();
Bundle args = new Bundle();
args.putInt(SupportFragment.ARG_NAME, name);
args.putString("screenfrom", screenfrom);
fragment.setArguments(args);
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();

You cannot pass fragments in bundles, you can however send extras with your intent and in the receiving activity get the intent and replace the fragment container with a fragment based on the value of the intent.

How to transfer data from one activity to a fragment with Firebase?

Hey I was wondering how I could transfer data from one activity to a fragment using fire base. I have edit text in the activity class and a list view in the Fragment.
I would like to display the information throughout the app database so that other users can see and edit the information too.

I dont know if the IDE matters but passing information to a fragment is usually done with fragment arguments. You need to create a static "newInstance" method in your fragment that you can call from the activity and pass whatever info to the fragment through it. Something like this:
public static mListFragment newInstance(String fromActivity) {
mListFragment fragment = new mListFragment ();
Bundle args = new Bundle();
args.putString("STIRNG_FROM_ACTIVITY", fromActivity);
fragment.setArguments(args);
return fragment;
}
You can then call the method from the activity like this:
FragmentManager fm = getFragmentManager().beginTransaction();
mListFragment fragment = new mListFragment();
fragment = mListFragment.newInstance("info_to_send");
fragmentTransaction.add(R.id.fragments_frame, fragment);
From here you can even persist the info across device screen orientation changes..

Just use firebaseRef to setValue() and set the value from the edittext.
Add ValueListener on the fragment to get the same value from dataSnapshot.
:D
https://github.com/firebase/quickstart-java/tree/master/database/src/main/java/com/google/firebase/quickstart

Android Fragments sharing info ways

i have a internal discussion about what way is better to share info between fragments contents inside a controller activity. In a first classical way, you can set arguments when you are going to replace fragments as follows:
//Just now i'm inside Fragment 1 and i'll navigate to Fragment 2
Fragment newFragment = getFragmentManager().findFragmentByTag(Fragment2.TAG);
Bundle b = new Bundle();
b.putBoolean("test1", true);
// Create new fragment and transaction
if(newFragment==null)
newFragment = Fragment2.newInstance(b);
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN)//.setCustomAnimations(R.anim.enter_anim, R.anim.exit_anim)
.replace(R.id.fragment_place, newFragment, Fragment2.class.getName())
.addToBackStack(newFragment.getClass().getName())
.commit();
The newInstace method does as i meant above, so, with setArguments:
public static Fragment2 newInstance(Bundle arguments){
Fragment2 f = new Fragment2();
if(arguments != null){
f.setArguments(arguments);
}
return f;
}
But Fragment1 and Fragment2 they are both inside a ControllerActivity, so i can also think about a second way to share information obtained in Fragment1 towards Fragment2, through declaring attributes in the ControllerActivity, so i could do (declaring previously an object in the activity) as follows inside any fragment:
EDIT
public class ControllerActivity extends FragmentActivity{
int value = 5;
...
And then, inside my fragment:
((SplashActivity)getActivity()).value = 10; //i can assign or recover value when i desire
My question is what inconveniences would have doing as the second way.

Writing code using 2nd way is fast. But the problem is you have to cast the general Activity to the more specific SplashActivity in which the value variable exists. If you want to use the Fragment with another Activity, or you want a Fragment to be a general purpose UI component you have to use interface for passing the data.
As mentioned in comments, bellow links provide more details about interface/callback method:
android docs
video from slidenerd
Hope this answers your question.

Showing a particular fragment via intent call

I know we can move between activities via an intent call. But is there a way to move from one activity to a particular fragment hosted by an activity? For example if I have an activity A which hosts 2 fragments f1 and f2,is there a way to move from another activity say B to fragment f2 directly via intent call?
Thanks in advance.

hmm it is not possible directly via intent call, you will have to start activity A and via an extra/bundle in intent you can specify to activity A to open fragment f2, meaning you will have to write the logic yourself... not possible directly .. Cheers
Try this in Activity B it will open ActivityA and its sending a string which you can check in that activity, based on that string you will add fragment:
Intent i = new Intent(this, ActivityA.class);
i.putExtra("toOpen", "fragment 1");
startActivity(i);
and in ActivityA oncreate
Bundle extras = getIntent().getExtras();
String toOpen = extras.getString("toOpen");
check toOpen string and open appropriate fragment..
Are you asking how to show/add fragments as well , because thats a complete new ball game :) but this would be a nice starts for managing fragments http://developer.android.com/guide/components/fragments.html

When u open a fragment from a activity on a button click the
write this code
Fragment myfragment;
myfragment = new Your_Fragment_Name();
FragmentManager fm = getFragmentManager();
FragmentTransaction fragmentTransaction = fm.beginTransaction();
fragmentTransaction.add(R.id.container, myfragment);
fragmentTransaction.commit();
In my code an id is used: container. This is the id of layout in which Fragment is open.
if u also send a value from activity to with the fragment then
Bundle bundle = new Bundle();
bundle.putInt("value",value );
and
myfragment.setArguments(bundle);
this line is add after create the FragmentManager object
This code is very helpful