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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.

Android webview not loading url?

I have a webview set up but when I click on the item, an empty fragment shows up where the actual web item is supposed to be. I have tried loading my urls on mobile browser and they work fine. I have an internet permission in android manifest.
web view layout file
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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=".activities.HomeActivity">
<WebView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/webView"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
webview fragment
public class WebViewDetailsFragment extends Fragment {
private WebView detailsWebView;
private String articleSource;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_web_view_details, container, false);
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
detailsWebView = view.findViewById(R.id.webView);
detailsWebView.getSettings().setLoadsImagesAutomatically(true);
detailsWebView.getSettings().setJavaScriptEnabled(true);
detailsWebView.getSettings().setUseWideViewPort(true);
detailsWebView.getSettings().setLoadWithOverviewMode(true);
detailsWebView.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);
// Configure the client to use when opening URLs
detailsWebView.setWebViewClient(new WebViewClient());
setItems();
detailsWebView.loadUrl(articleSource);
}
private void setItems(){
NewsArticle newsArticle = NewsFragment.news.get(NewsAdapter.pos);
articleSource = "https://www.google.com";
}
}

I too tried your Code. it is working fine and good.There may be a chances of issue in fragmentManager. Did you checked the view is visible or not

How to close a parent fragment from child fragment in navigation component

I'm creating an app that need to nested navigation graphs and a want to close a parent fragment from child fragment.
I can close a fragment by calling
getActivity().getSupportFragmentManager().popBackStack();
with this i can only close the current top fragment in back stack.
in this picture i want to close Fragment2 from Framgent3.
EDIT:
I'm opening Fragment2 with:
Navigation.findNavController(getView()).navigate(R.id.action_fragment1_to_fragment2);
Fragment1:
public class Fragment1 extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment1, container, false);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
getView().findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Navigation.findNavController(v).navigate(R.id.action_fragment1_to_fragment2);
}
});
}
}
Fragment1 layout:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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"
android:background="#color/colorPrimaryDark">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Framgent2:
public class Fragment2 extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment2, container, false);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
public void close () {
getActivity().getSupportFragmentManager().popBackStack();
}
}
in Fragment2 i have another graph, Fragment2 layout:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
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"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<fragment
android:id="#+id/child_graph_base"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:defaultNavHost="true"
app:navGraph="#navigation/child_graph" />
</android.support.constraint.ConstraintLayout>
Fragment3:
public class Fragment3 extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment3, container, false);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
getView().findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
NavHostFragment navHostFragment = (NavHostFragment) getParentFragment();
Fragment2 fragment2 = (Fragment2) navHostFragment.getParentFragment();
fragment2.close();
}
});
}
}
Fragment3 layout:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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"
android:background="#color/colorPrimaryDark">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Main Graph (MainActivity):
<?xml version="1.0" encoding="utf-8"?>
<navigation 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:id="#+id/main_graph"
app:startDestination="#id/fragment1">
<fragment
android:id="#+id/fragment1"
android:name="alistar.navigation.fragments.Fragment1"
android:label="fragment1"
tools:layout="#layout/fragment1" >
<action
android:id="#+id/action_fragment1_to_fragment2"
app:destination="#id/fragment2" />
</fragment>
<fragment
android:id="#+id/fragment2"
android:name="alistar.navigation.fragments.Fragment2"
android:label="fragment2"
tools:layout="#layout/fragment2" />
</navigation>
Child Graph (in Framgent2)
<?xml version="1.0" encoding="utf-8"?>
<navigation 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:id="#+id/child_graph"
app:startDestination="#id/fragment3">
<fragment
android:id="#+id/fragment3"
android:name="alistar.navigation.fragments.Fragment3"
android:label="fragment3"
tools:layout="#layout/fragment3" />
</navigation>

i solved the problem by calling close() method in the parent fragment (Fragment2) from Fragment3. i changed close method to this:
public void close () {
Navigation.findNavController(getView()).popBackStack();
}
also i removed:
app:defaultNavHost="true"
from my child graph and worked OK!

include the graph of (frag2,frag3) in frag1's graph using include
<include app:graph="#navigation/frag1_graph"/>
and then:
add an action to your fragment3 with appropriate Destination and popUpTo arguments
<fragment
android:id="#+id/Fragment3"
android:name="whatever"
android:label="whatever"
tools:layout="#layout/whatever" >
<action
android:id="#+id/action_Fragment3_to_Fragmen1"
app:destination="#id/Fragment1"
app:launchSingleTop="true"
app:popUpTo="#+id/Fragment1"
app:popUpToInclusive="true" /> </fragment>
and then
findNavController(fragment).navigate(R.id.action_Fragment3_to_fragment1)
and then display fragment3 again. i think that's what you want right?

ArrayAdapter additions not showing in ListView

I have a Android fragment containing a ListView, and I have attached an ArrayAdapter to the ListView, but when I insert items into the ArrayAdapter, the ListView only shows the first item.
onCreateView iterates over my Technologies, if they're unlocked, it adds them to the ArrayList shownTechs, but only the first item ever appears
public class TabTechnologyList extends Fragment {
private static final String TAB_NAME = "tab_name";
private ListView techList;
private ArrayList<Technology> shownTechs = new ArrayList<>();
ArrayAdapter<Technology> techListAdapter;
public TabTechnologyList() { }
public static TabTechnologyList newInstance() {
TabTechnologyList fragment = new TabTechnologyList();
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
tabData = Globals.getTabData();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_technology_list, container, false);
techList = (ListView) view.findViewById(R.id.tabTechListList);
techListAdapter = new ArrayAdapter<>(getActivity().getApplicationContext(), R.layout.layout_techlist_element, shownTechs);
techList.setAdapter(techListAdapter);
for(Technology tech: tabData.getTechnologies()) {
shownTechs.add(tech);
}
//Only the first one is shown on the screen
return view;
}
}
}
When I google for similar issues, people seem to be recreating the ArrayAdapter instead of editing the existing one, but I'm not doing that, and cant' figure out what problem remains. Any suggestions?
fragment_technology_list.xml:
<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"
tools:context="com.tbohne.kittens.front.TabTechnologyList"
>
<ListView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/tabTechListList" />
</RelativeLayout>
layout_techlist_element.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</TextView>
Addition
I have just realized that this fragment is not filling the parent height, and is only tall enough to show the one entry, as if the fragment height were wrap_content. (I can't scroll it, so it appears as if there's only the one). This makes me think the nesting of fragments may be related, so here's the code that creates the fragment:
public class TabTechnology extends Fragment {
private TabTechnologyList table;
private OnFragmentInteractionListener mListener;
public TabTechnology() {}
public static TabTechnology newInstance(String tabName) {[SNIP]}
#Override public static onAttach(Activity activity) {[SNIP]}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_technology, container, false);
table = TabTechnologyList.newInstance(tabName);
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
transaction.add(R.id.view_table, table);
transaction.commit();
return view;
}
}
fragment_technology.xml
<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"
tools:context="com.tbohne.kittens.front.TabTechnology"
android:orientation="vertical">
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:id="#+id/view_table"
android:layout_above="#+id/view_details" />
<View android:layout_width="match_parent"
android:layout_height="1px"
android:background="?android:attr/listDivider" />
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:id="#+id/view_details"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true" />
</LinearLayout>

Putting the Fragment inside the ScrollView was the source of the problem. Simply replaced those with FrameLayout, and suddenly everything magically works. Very strange.
I suspect the problem has something to do with nesting scrollable objects.

ListFragment: Runtime error "Your content must have a ListView whose id attribute is 'android.R.list'

I have a listfragment class:
public class activityfeedScreen extends ListFragment implements OnItemClickListener {
private ListView activityfeed_feedList_listView;
private ActivityFeedBaseAdapter adapter;
public static final activityfeedScreen newInstance()
{
activityfeedScreen fragment = new activityfeedScreen();
Bundle bdl = new Bundle(1);
fragment.setArguments(bdl);
return fragment;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.activity_activityfeed_screen, container, false);
activityfeed_feedList_listView = (ListView)v.findViewById(R.id.activityfeed_feedList_listView);
activityfeed_feedList_listView.setAdapter(adapter);
activityfeed_feedList_listView.setOnItemClickListener(this);
return v;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
public void onItemClick(AdapterView<?> activityfeedlistview, View view, int position, long itemID) {
Intent intent_activityfeed_showitemdescription = new Intent(view.getContext(), activityfeedItemScreen.class);
startActivity(intent_activityfeed_showitemdescription);
}
}
In this class I am getting an error at the line:
activityfeed_feedList_listView = (ListView)v.findViewById(R.id.activityfeed_feedList_listView);
I initially thought it was a problem due to the getView() being null so I moved that from the onCreate method to the onCreateView() method. But I am getting the runtime error as stated in the title.
Here is my layout file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:background="#E5E5E5"
android:layout_height="match_parent">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:layout_marginRight="10dp"
android:layout_marginLeft="10dp">
<ImageView
android:id="#+id/activityfeed_profilePicture_imageView"
android:layout_width="75dp"
android:layout_height="75dp"
android:layout_centerVertical="true"
android:layout_alignParentLeft="true"
android:src="#drawable/default_profile"/>
</RelativeLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#B9B9B9"
android:layout_marginTop="20dp">
<ListView
android:id="#+id/activityfeed_feedList_listView"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</ListView>
</RelativeLayout>
I understand that I must change the listview id to
android:id="#android:id/list"
but I am not sure then how to call that in my onCreateView method.
Thanks for all your help!

Yes. First of all you do have to change the ID of your ListView like so:
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</ListView>
In your onCreateView you can reference the ID by android.R.id.list. This is because Android built-in resource reside in android.R. You can also find there drawables, styles, etc. (you can call them in a similar maneer).
Taking the above into consideration, your onCreateView method should look like this :
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.activity_activityfeed_screen, container, false);
activityfeed_feedList_listView = (ListView)v.findViewById(android.R.id.list);
activityfeed_feedList_listView.setAdapter(adapter);
activityfeed_feedList_listView.setOnItemClickListener(this);
return v;
}
That's all ;)

In onCreateView() you need to provide a layout that has a ListView with and id of #android:id/list.
ListFragment provides some helper methods (e.g setListAdapter()) that require the layout to have a ListView with that id so it can reference it and set the adapter for you.