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First fragment remains in the background after transition

I am currently trying to create an app having a splash screen, a login screen and a register screen.
The only way to achieve exactly what I need is through fragments. Though when I try to transition from the splash screen to the login fragment the text view which was part of the splash screen remains. The same happens after transitioning from the login fragment to the register fragment as well as from the register fragment back to the login fragment. It is important to note that there is no issue during transitioning between login and register or between register and login - except the fact that the edit text stays there.
My MainActivity.java
public class StartActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_start);
}
#Override
public void onBackPressed(){
Toast.makeText(getApplicationContext(), "Back button is disabled", Toast.LENGTH_SHORT).show();
}
}
My layout for MainActivity
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".StartActivity"
android:background="#mipmap/background">
<fragment
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/viewpagerstart"
android:layout_centerInParent="true"
android:name="com.example.distributedsystemsui.SplashFragment">
</fragment>
</RelativeLayout>
The SplashScreen.java
public class SplashFragment extends Fragment {
LinearLayout linearLayout;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_splash, container, false);
linearLayout = (LinearLayout) view.findViewById(R.id.f_linearsplash);
Animation animation_fadein = AnimationUtils.loadAnimation((StartActivity)getActivity(), R.anim.fade_in);
linearLayout.startAnimation(animation_fadein);
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
public void run() {
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.setCustomAnimations(R.anim.slide_enter_left, R.anim.slide_exit_left,
R.anim.slide_enter_right, R.anim.slide_exit_right);
LoginFragment loginFragment = LoginFragment.newInstance();
ft.replace(R.id.viewpagerstart, loginFragment);
ft.commit();
}
}, 3000);
return view;
}
}
And the layout for the SplashScreen fragment.
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LoginFragment"
android:background="#color/Tranparent"
android:id="#+id/frame_splash">
<LinearLayout
android:id="#+id/f_linearsplash"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ImageView
android:id="#+id/f_splashlogo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="70dp"
android:background="#FFFFFF"/>
<TextView
android:id="#+id/f_splashtext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/app_name"
android:layout_gravity="center_horizontal"
android:layout_marginTop="100dp"
android:background="#FFFFFF"/>
</LinearLayout>
</FrameLayout>
All my search led back to nothing.
I can only assume that either the below contained in the MainActivity.xml creates a confusion (which I tried to change but no luck):
android:name="com.example.distributedsystemsui.SplashFragment"
or that I am doing a mistake in the SplashScreen.java that I cannot locate, even though I tried for more than 5 hours to make it work.

The problem is that you cannot replace fragments added via the <fragment> tag.
Instead, you should either:
1) Switch to FragmentContainerView, which was added in Fragment 1.2.0. It does not suffer from the same issue as the <fragment> tag and lets you do replace operations without issues:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".StartActivity"
android:background="#mipmap/background">
<androidx.fragment.app.FragmentContainerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/viewpagerstart"
android:layout_centerInParent="true"
android:name="com.example.distributedsystemsui.SplashFragment">
</androidx.fragment.app.FragmentContainerView>
</RelativeLayout>
2) Use a FrameLayout in your layout and manually add the SplashFragment in your activity (this is essentially what FragmentContainerView does for you):
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".StartActivity"
android:background="#mipmap/background">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/viewpagerstart"
android:layout_centerInParent="true">
</FrameLayout>
</RelativeLayout>
which means you need to add the SplashFragment manually:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_start);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.viewpagerstart, new SplashFragment())
.commit()
}
}

I think it is better to do the fragment transactions from your activity instead of doing it from your fragment. You might consider having functions in your MainActivity as follows.
public class StartActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_start);
}
public void goToLoginFragment() {
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.setCustomAnimations(R.anim.slide_enter_left, R.anim.slide_exit_left,
R.anim.slide_enter_right, R.anim.slide_exit_right);
LoginFragment loginFragment = LoginFragment.newInstance();
ft.replace(R.id.viewpagerstart, loginFragment);
ft.commit();
}
public void goToRegisterFragment() {
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.setCustomAnimations(R.anim.slide_enter_left, R.anim.slide_exit_left,
R.anim.slide_enter_right, R.anim.slide_exit_right);
LoginFragment registerFragment = RegisterFragment.newInstance();
ft.replace(R.id.viewpagerstart, registerFragment);
ft.commit();
}
#Override
public void onBackPressed(){
Toast.makeText(getApplicationContext(), "Back button is disabled", Toast.LENGTH_SHORT).show();
}
}
And then from your SplashFragment call the function that is defined in your activity.
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
public void run() {
((MainActivity) getActivity()).goToLoginFragment();
}
}, 3000);
I hope that solves the problem.

Stuck at adding/changing fragments in android studio

even though i googled extensively, i cant find a solution to my problem. I am new to programming, so please consider that in your answer.
I have a Main Activity and a Menu bar at the bottom. Since the menu bar is scrollable and i want to have it for all the different screens, i figured out that i could - instead of making an intent for a new activity - just put a fragment on top of the existing screen (and spare out the menu bar).
But i fail at programatically opening that fragment. I tried the following, but it doesnt even recognice the ID of the FrameLayout.
I was trying to replace a FrameLayout in my Main Activities' xml file with the fragment:
FragmentManager fragmentManager = getSupportFragmentManager();
android.support.v4.app.FragmentTransaction ft =
fragmentManager.beginTransaction();
ft.replace(R.id.idOfFrameLayout, new nameOfFragmentClass());
ft.commit();
EDIT:
It works after i implemented OnFragmentInteractionListener into the Main Activity. Thanks to everyone!

My original answer suggested using add instead of replace for the Fragment transaction. I have since learned that either can be used in this case. For more info on the differences, see this, this and this
Since my add/replace idea was off base, I've changed my answer to a simple Fragment tutorial. One Fragment inflated from one Activity. I've included the code for Fragment to Activity communication (the reason for the OPs problem) but left comments on what could be deleted if that's not needed. The only thing done in the Activity is launching the Fragment then receiving a message back from that Fragment. The Fragment has a button that will cause a message to be sent back to the Activity. The message will then be Logged.
In both classes, if no communications is needed from the Fragment to the Activity, delete anything that is marked TODO:
// this is what controls whether you use a Fragment from the support library
import android.support.v4.app.FragmentManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
public class SimpleActivity extends AppCompatActivity
// TODO: delete "implements SimpleFragment.OnFragmentInteractionListener" from this
// line (leave the '{')
implements SimpleFragment.OnFragmentInteractionListener {
private static final String TAG = SimpleActivity.class.getSimpleName();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_simple);
SimpleFragment fragment = new SimpleFragment();
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.add(R.id.fragment_container, fragment)
.commit();
}
// TODO: this entire method can be deleted
#Override
public void onFragmentInteraction(String message) {
// This is where you can act on the message from the Fragment. You would do
// things that are done from an Activity or you may pass the message on
// to another Fragment.
Log.d(TAG, message);
}
}
Most import statements aren't shown, I left this one in to indicate using the support library
import android.support.v4.app.Fragment;
public class SimpleFragment extends Fragment {
private OnFragmentInteractionListener mListener; // TODO: delete this line
public SimpleFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_simple, container, false);
Button button = (Button)rootView.findViewById(R.id.msg_button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// TODO: delete these 3 lines, do something else with the button click
if (mListener != null) {
mListener.onFragmentInteraction("Message from Fragment");
}
}
});
return rootView;
}
// TODO: this entire method can be deleted
#Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
// TODO: this entire method can be deleted
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
// TODO: this entire method can be deleted
public interface OnFragmentInteractionListener {
void onFragmentInteraction(String message);
}
}
Now the layout files. 1st activity_simple.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/fragment_container"
>
</FrameLayout>
</android.support.constraint.ConstraintLayout>
Then fragment_simple.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="Info to Activity"
android:id="#+id/msg_button"
/>
</RelativeLayout>
This is a very basic sample. Here is a more extensive guide for Fragment usage.

When you use the 'replace' method, you need 3 things:
1- the container id, which is the view that is going to hold your fragment's view.
2- the fragment instance you want to use and
3- the fragment instance's tag, but this is optional.
Given that, let's say you have the following layout for your activity:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
...
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<FrameLayout
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</android.support.v4.widget.NestedScrollView>
<android.support.design.widget.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:background="?android:attr/windowBackground"
app:menu="#menu/navigation" />
</android.support.design.widget.CoordinatorLayout>
The FrameLayout which id is "container" is the holding view, so that's the id you've gotta use:
ft.replace(R.id.container, new nameOfFragmentClass());

I suggest use this library to manage fragments:
FragmentManagerAndroid

Fragment Add causing me an error

I am trying to figure out why I am suddenly getting an error when I try to add a fragment.
public class MainActivity extends Activity implements Communicator {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView((int) R.layout.activity_main);
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.add(R.id.fragA, new FragmentA());
//I get errors on each of the adds
ft.commit();
FragmentTransaction ft2 = getFragmentManager().beginTransaction();
ft2.add(R.id.fragB, new FragmentB());
ft2.commit();
FragmentTransaction ft3 = getFragmentManager().beginTransaction();
ft3.add(R.id.fragC, new FragmentC());
ft3.commit();
}
public void respond(String str) {
//I also get an error on the following line
((FragmentB)getFragmentManager().findFragmentById(R.id.fragB)).changeText(str);
}
}
Just using the import of FragmentTransaction, I haven't made my own class.
This is my fragment A code:
public class FragmentA extends Fragment implements OnClickListener {
Button btn;
Communicator comm;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fraga, container, false);
}
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
this.btn = (Button) getActivity().findViewById(R.id.buttonA);
this.btn.setOnClickListener(this);
this.comm = (Communicator) getActivity();
}
public void onClick(View v) {
this.comm.respond("Hello from Fragment A");
}
}
xml for the activity, I am not a hundred percent sure if this will fix it but would raising the API of the project make any difference at all?
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.tannerlangan.week11fragtalk.MainActivity">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:background="#ff83ff3e"
android:id="#+id/fragA"></RelativeLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_centerVertical="true"
android:layout_alignParentStart="true"
android:background="#ff71e7ff"
android:id="#+id/fragB"></RelativeLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true"
android:background="#ff6d9aff"
android:id="#+id/fragC"></RelativeLayout>
</RelativeLayout>

Your fragments probably using android.support.v4.app.Fragment instead of android.app.Fragment. The quick fix is to change the signature of your fragments to something like this:
public class FragmentA extends android.app.Fragment implements OnClickListener
This is very common with programs that mix the components from support libraries and the non-support one

Try using getSupportFragmentManager() instead of getFragmentManager(). getSupportFragmentManager() is for API<14.

In your project check whether you have imported the same Fragment class in both your FragmentA and MainActivity. You might have imported android.support.v4.app.Fragment in your fragment and in MainActivity you may have imported android.app.Fragment.
If you're minSdk is <14 use fragment, fragmentManager etc from the support library(i.e android.support.v4.app.fragment and same for the fragment manager) else just import the standard fragment class(i.e android.app.Fragment).
P.S : It would be really helpfull if you provide your Error in the question as well.

ListFragment appearing twice on phone

I'm seeing an undesired appearance of my list fragment when I run my app on the phone emulator. On the tablet emulator it appears once but on the phone emulator it appears twice. How can I fix this error for the list to appear on the phone emulator only once?
MainActivity.java
public class MainActivity extends ActionBarActivity {
private boolean mTwoPane;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentMainList newFragment = new FragmentMainList();
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.master_container, newFragment);
transaction.commit();
if (findViewById(R.id.detail_container) != null) {
mTwoPane = true;
}
}
}
activity_main.xml
<fragment
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/master_container"
android:name="com.apptacularapps.exitsexpertlondonlite.FragmentMainList"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".FragmentMainList"
tools:layout="#android:layout/list_content"/>
activity_main.xml (sw600dp)
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:showDividers="middle"
tools:context=".MainActivity" >
<RelativeLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:id="#+id/master_container"/>
<FrameLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="3"
android:id="#+id/detail_container"/>
</LinearLayout>
FragmentMainList.java
public class FragmentMainList extends android.support.v4.app.Fragment {
ListView list_main;
String[] listContent = {
"Item 1",
"Item 2",
"Item 3"
};
private boolean mTwoPane;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
View v = inflater.inflate(R.layout.fragment_main_list, container, false);
list_main = (ListView)v.findViewById(R.id.list_main);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(),android.R.layout.simple_list_item_1,listContent);
list_main.setAdapter(adapter);
return v;
}
}

Please move the logic to add fragment inside the if loop you have.

Although you've already understood how to make it work, I'll try to explain how to make it work properly.
What you do is in fact this:
If on small screen - add the fragment statically (in XML)
If on larger screen - add the fragment dynamically (with FragmentTransaction)
It looks weird that the method by which you get the desired functionality depend on the screen size - there should be no correlation between these factors.
What you ought to do (IMHO) is to add this fragment dynamically in both cases - just change your Fragment tag in the first XML to FrameLayout and everything will work as expected.

No view found for id 0x7f090005

I'm starting to build a simple Android app so when I press my video button it calls a fragment which contains the video player, but I'm always getting: No view found for id 0x7f090005...
I wonder if you give me a hand by figuring out what is wrong in the code that I'm writing.
Here is my MainActivity.java file:
public class MainActivity extends Activity {
private Button mVideoButton;
Fragment fragment;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
mVideoButton = (Button)findViewById(R.id.videoButton);
// Video Button
mVideoButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
FragmentVideo sf = new FragmentVideo();
ft.add(R.id.fragmentVideo, sf);
ft.commit();
}
});
}
}
Then I have my main_activity.xml:
<?xml version="1.0" encoding="utf-8"?>
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/activityStart" >
<ImageView
android:src="#drawable/armstrong_on_moon"
android:contentDescription="#string/description"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerInside"
android:layout_weight="1" />
<TableRow
android:gravity="center|bottom"
android:layout_weight="0">
<Button
android:id="#+id/videoButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/video" />
</TableRow>
Next, my FragmentVideo.java class:
public class FragmentVideo extends Fragment{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState ){
View v = inflater.inflate(R.layout.fragment_video, parent, false);
return v;
}
}
And at last, the fragment_video.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="#+id/fragmentVideo" >
<VideoView
android:id="#+id/video"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity="center" />
<ProgressBar
android:id="#+id/prog"
android:layout_width="70dp"
android:layout_height="70dp"
android:layout_gravity="center" />
</LinearLayout>
Please let me know if I'm doing something wrong or if I'm missing something as I can see where the issue lays.
Thanks very much for any help in advance.
EGMWEB

On ft.add() the int parameter refers to the container to which you want to add the Fragment; you are trying to add the Fragment to the Fragment's own layout (Android doesn't find the View because it is not inflated yet, if it did it will throw and Exception in this case; you cannot add a Fragment to its own layout). You want to replace R.id.fragmentVideo with R.id.activityStart to add the Fragment to the current TableLayout that is part of the already inflated main_activity layout

Could you check whats the equivalent view for the id '0x7f090005' in the R.java file. It should be under gen folder of your project. The framework is not able to find this under the resource file that you have in this java class.