Develop Reference

Collapsing AppBarLayout not scrolling with TabLayout and NestedScrollView

I have an issue with scrolling Collapsing AppBar, when I am trying to scroll it touching the AppBarLayout part. And also it sometimes scrolling not smoothly.
Here is short (1m 30s) video of issue: https://www.youtube.com/watch?v=n32N9Z4S3SA&feature=youtu.be
Here is link to simple project (only this issue on github): https://github.com/yozhik/Reviews/tree/master/app/src/main/java/com/ylet/sr/review
I'm using: com.android.support:appcompat-v7:27.1.1
There is issue on offsite: https://issuetracker.google.com/issues/37050152
How it is: https://www.youtube.com/watch?v=xWadOVEaTSY&feature=youtu.be
How it should be: https://www.youtube.com/watch?v=J8ITp6RusZo&feature=youtu.be
Does anybody know how to fix this issue you saw on video? I created absolutely simple layouts to avoid any side effects, but bug still reproduced. Thanks in advance.
Description:
CollapsingActivity - activity with Collapsing AppBarLayout. Which loads one or two fragments into "fragment_content_holder" and it has TabLayout
to switch between fragments in view pager.
In activity method onCreate() - I'm just simulating request to server (loadData), and when some fake data is loaded - I am showing fragments in view pager, on first call - I am creating new TabMenuAdapter extends FragmentPagerAdapter, populate it with fragments and save links to instances. On the next call -
I don't create fragments from scratch and just populate them with fresh data.
MenuFragment1, MenuFragment1 - two fragments.
MenuFragment1 - has method public void setupData(SomeCustomData data), to set new data, not recreating fragment on network reconnect.
NetworkStateReceiver - listens to network change and send notifications.
TabMenuAdapter - just simple class to hold fragments.
Next is just copy/paste of code:
public class CollapsingActivity extends AppCompatActivity implements ChangeNetworkNotification {
private static int dataReloadIteration = 0;
private SomeCustomData dummyDataFromServer;
#BindView(R.id.root_layout)
CoordinatorLayout root_layout;
#BindView(R.id.app_bar_layout)
AppBarLayout app_bar_layout;
#BindView(R.id.collapsing_toolbar_layout)
CollapsingToolbarLayout collapsing_toolbar_layout;
#BindView(R.id.view_pager_layout)
ViewPager viewPager;
#BindView(R.id.tab_layout)
TabLayout tabLayout;
#BindView(R.id.collapsing_data_1_txt)
TextView collapsing_data_1_txt;
private NetworkStateReceiver networkStateReceiver;
private boolean isConnected;
protected Fragment currentFragment;
protected Fragment previousFragment;
protected FragmentManager fragmentManager;
private boolean dataLoading = false;
private boolean isCreated = false;
private MenuFragment1 menu1Fragment1;
private MenuFragment2 menu1Fragment2;
private TabMenuAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
Log.d("TEST", "CollapsingActivity.onCreate");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_collapsing);
ButterKnife.bind(this);
fragmentManager = getSupportFragmentManager();
networkStateReceiver = new NetworkStateReceiver();
networkStateReceiver.setNetworkReceiver(this);
IntentFilter intentFilterForNetwork = new IntentFilter("android.net.conn.CONNECTIVITY_CHANGE");
registerReceiver(networkStateReceiver, intentFilterForNetwork);
initToolbar();
loadData();
}
#Override
protected void onStart() {
Log.d("TEST", "CollapsingActivity.onStart");
super.onStart();
IntentFilter intentFilterForNetwork = new IntentFilter("android.net.conn.CONNECTIVITY_CHANGE");
registerReceiver(networkStateReceiver, intentFilterForNetwork);
}
private void initToolbar() {
Log.d("TEST", "CollapsingActivity.initToolbar");
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar_layout);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayShowTitleEnabled(false);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}
private void loadData() {
Log.d("TEST", "CollapsingActivity.loadData");
dataLoading = true;
Thread t = new Thread(new Runnable() {
#Override
public void run() {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(CollapsingActivity.this, "Data loaded.", Toast.LENGTH_SHORT).show();
Log.d("TEST", "CollapsingActivity.Data loaded.");
dataReloadIteration++;
dummyDataFromServer = getDummyObjectFromServer();
collapsing_data_1_txt.setText(dummyDataFromServer.Name); //Set data from server in collapsing part of Activity
boolean showOneView = false;
if (showOneView) {
initSingleView();
} else {
if (!isCreated) {
initTabView();
} else {
menu1Fragment1.setupData(dummyDataFromServer); //Set the data from server to fragment, not reloading it, just updating data
}
}
dataLoading = false;
}
});
}
});
t.start();
}
private SomeCustomData getDummyObjectFromServer() {
SomeCustomData dto = new SomeCustomData();
dto.Age = dataReloadIteration;
dto.Name = "Name " + dataReloadIteration;
return dto;
}
private void initSingleView() {
Log.d("TEST", "CollapsingActivity.initSingleView");
tabLayout.setVisibility(View.GONE);
viewPager.setVisibility(View.GONE);
showFragmentWithoutBackStack(R.id.fragment_content_holder, new MenuFragment1());
}
private void initTabView() {
if (!isCreated) {
Log.d("TEST", "CollapsingActivity.initTabView");
tabLayout.setVisibility(View.VISIBLE);
viewPager.setVisibility(View.VISIBLE);
setupViewPager(viewPager);
tabLayout.setupWithViewPager(viewPager);
isCreated = true;
}
}
private void setupViewPager(ViewPager viewPager) {
Log.d("TEST", "CollapsingActivity.setupViewPager");
menu1Fragment1 = MenuFragment1.newInstance(dummyDataFromServer);
menu1Fragment2 = MenuFragment2.newInstance();
adapter = new TabMenuAdapter(getSupportFragmentManager());
adapter.addFragment(menu1Fragment1, "Menu 1");
adapter.addFragment(menu1Fragment2, "Menu 2");
viewPager.setAdapter(adapter);
}
#Override
protected void onDestroy() {
Log.d("TEST", "CollapsingActivity.onDestroy");
super.onDestroy();
unregisterReceiver(networkStateReceiver);
}
#Override
public void networkStateIsChanged(boolean isConnected) {
this.isConnected = isConnected;
Log.d("TEST", "CollapsingActivity.networkStateIsChanged.isConnected: " + isConnected);
if (isConnected) {
Toast.makeText(CollapsingActivity.this, "Connection received.", Toast.LENGTH_SHORT).show();
if (!dataLoading) {
loadData();
}
} else {
Toast.makeText(CollapsingActivity.this, "Connection lost.", Toast.LENGTH_SHORT).show();
}
}
protected void showFragmentWithoutBackStack(int containerViewId, Fragment fragment) {
Log.d("TEST", "CollapsingActivity.showFragmentWithoutBackStack");
previousFragment = currentFragment;
currentFragment = fragment;
String fragmentTag = fragment.getClass().getSimpleName();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
if (previousFragment != null) {
fragmentTransaction.remove(previousFragment);
}
fragmentTransaction.add(containerViewId, fragment, fragmentTag)
.commitNowAllowingStateLoss();
}
}
activity's layout:
<?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:id="#+id/root_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="false"
android:background="#color/white"
android:stateListAnimator="#drawable/appbar_shadow"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/green"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:title=""
app:titleEnabled="false">
<include
layout="#layout/appbar_collapsing_part"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="?attr/actionBarSize"
app:layout_scrollFlags="scroll|exitUntilCollapsed" />
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#color/green"
android:stateListAnimator="#drawable/appbar_shadow"
app:layout_collapseMode="pin"
app:popupTheme="#style/AppTheme.PopupOverlay"
app:theme="#style/ToolbarMenuItemsBackGroundTheme">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/title_txt"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_toStartOf="#+id/star_img"
android:ellipsize="end"
android:fontFamily="sans-serif-medium"
android:gravity="center_vertical"
android:maxLines="1"
android:textColor="#color/colorPrimaryDark"
android:textSize="19sp" />
<ImageView
android:id="#+id/star_img"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_centerInParent="true"
android:layout_gravity="center"
android:layout_marginEnd="24dp"
android:padding="10dp"
android:src="#drawable/ic_favorite_filled" />
</RelativeLayout>
</android.support.v7.widget.Toolbar>
</android.support.design.widget.CollapsingToolbarLayout>
<android.support.design.widget.TabLayout
android:id="#+id/tab_layout"
android:layout_width="wrap_content"
android:layout_height="48dp"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:background="#45b0b2"
android:visibility="gone"
app:tabBackground="#drawable/backgr_blue_transparent_selector"
app:tabGravity="center"
app:tabIndicatorColor="#color/colorPrimaryDark"
app:tabIndicatorHeight="2dp"
app:tabMinWidth="500dp"
app:tabMode="fixed"
app:tabSelectedTextColor="#color/colorPrimaryDark"
app:tabTextAppearance="#style/CustomTabLayout"
app:tabTextColor="#color/green" />
</android.support.design.widget.AppBarLayout>
<FrameLayout
android:id="#+id/fragment_content_holder"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/blue"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<android.support.v4.view.ViewPager
android:id="#+id/view_pager_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="gone"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
Fragment 1:
public class MenuFragment1 extends Fragment {
public SomeCustomData transferedDataFromActivity;
private TextView data_1_txt;
public static MenuFragment1 newInstance(SomeCustomData data) {
Log.d("TEST", "MenuFragment1.newInstance");
MenuFragment1 fragment = new MenuFragment1();
Bundle args = new Bundle();
args.putSerializable("DATA_FROM_ACTIVITY", data);
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.d("TEST", "MenuFragment1.onCreate");
if (getArguments() != null) {
this.transferedDataFromActivity = (SomeCustomData) getArguments().getSerializable("DATA_FROM_ACTIVITY");
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
Log.d("TEST", "MenuFragment1.onCreateView");
View v = inflater.inflate(R.layout.menu_fragment_1, container, false);
data_1_txt = (TextView) v.findViewById(R.id.data_1_txt);
setupInOnCreateView();
return v;
}
protected void setupInOnCreateView() {
Log.d("TEST", "MenuFragment1.setupInOnCreateView");
//initialization of all view elements of layout with data is happens here.
setupData(transferedDataFromActivity);
}
public void setupData(SomeCustomData data) {
Log.d("TEST", "MenuFragment1.setupData");
this.transferedDataFromActivity = data;
if (transferedDataFromActivity != null) {
data_1_txt.setText(transferedDataFromActivity.Name);
}
}
}
Fragment 1 layout:
<?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:background="#color/green"
android:orientation="vertical">
<TextView
android:id="#+id/data_1_txt"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/yellow"
android:text="Test"
android:textSize="20sp" />
<include layout="#layout/description_layout" />
</LinearLayout>
Fragment 2:
public class MenuFragment2 extends Fragment {
public static MenuFragment2 newInstance() {
Log.d("TEST", "MenuFragment2.newInstance");
MenuFragment2 fragment = new MenuFragment2();
return fragment;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
Log.d("TEST", "MenuFragment2.onCreateView");
View v = inflater.inflate(R.layout.menu_fragment_2, container, false);
setupInOnCreateView();
return v;
}
protected void setupInOnCreateView() {
Log.d("TEST", "MenuFragment2.setupInOnCreateView");
//initialization of all view elements of layout with data is happens here.
}
}
Fragment 2 layout:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.NestedScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/comments_scrollable_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="visible">
<LinearLayout
android:id="#+id/comments_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="100dp"
android:background="#color/yellow" />
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="100dp"
android:background="#color/blue" />
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="100dp"
android:background="#color/yellow" />
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
TabMenuAdapter:
public class TabMenuAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragments = new ArrayList<>();
private final List<String> mFragmentTitles = new ArrayList<>();
public TabMenuAdapter(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment, String title) {
mFragments.add(fragment);
mFragmentTitles.add(title);
}
#Override
public Fragment getItem(int position) {
return mFragments.get(position);
}
#Override
public int getCount() {
return mFragments.size();
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitles.get(position);
}
}

Try this
Activity layout
<android.support.design.widget.CoordinatorLayout 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:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
android:id="#+id/appBar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:title=""
app:titleEnabled="false">
<ImageView
android:layout_width="match_parent"
android:layout_height="256dp"
android:scaleType="fitXY"
android:src="#drawable/abc"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.CollapsingToolbarLayout>
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/colorPrimary"
app:layout_anchor="#id/appBar"
app:tabGravity="fill"
app:tabTextColor="#FFFFFF"
app:tabSelectedTextColor="#ff00"
app:tabMode="scrollable"
app:layout_anchorGravity="bottom" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
Activity code
public class MainActivity extends AppCompatActivity {
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new BlankFragment(), "TAB-ONE");
adapter.addFragment(new BlankFragment(), "TAB-TWO");
adapter.addFragment(new BlankFragment(), "TAB-THREE");
viewPager.setAdapter(adapter);
}
}
Fragment Code
public class BlankFragment extends Fragment {
public BlankFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_blank, container, false);
}
}
Fragment Layout
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.NestedScrollView 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"
xmlns:app="http://schemas.android.com/apk/res-auto">
<LinearLayout
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".BlankFragment">
<ImageView
android:layout_width="match_parent"
android:layout_height="250dp"
android:layout_margin="5dp"
android:scaleType="centerCrop"
android:src="#drawable/kid_goku" />
<ImageView
android:layout_width="match_parent"
android:layout_height="250dp"
android:layout_margin="5dp"
android:scaleType="centerCrop"
android:src="#drawable/kid_goku" />
<ImageView
android:layout_width="match_parent"
android:layout_height="250dp"
android:layout_margin="5dp"
android:scaleType="centerCrop"
android:src="#drawable/kid_goku" />
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
ViewPagerAdapter code
public class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
You can see the video here CollapsingToolbarLayout WITH TabLayout
You download the complete project from here CollapsingToolbarLayout WITH TabLayout

Try the below layout foryour 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"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/root_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="false"
android:background="#color/white"
android:stateListAnimator="#drawable/appbar_shadow"
android:theme="#style/AppTheme.AppBarOverlay"
tools:targetApi="lollipop">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/green"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:title=""
app:titleEnabled="false">
<include
layout="#layout/appbar_collapsing_part"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="?attr/actionBarSize"
app:layout_scrollFlags="scroll|exitUntilCollapsed" />
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#color/green"
android:stateListAnimator="#drawable/appbar_shadow"
app:layout_collapseMode="pin"
app:popupTheme="#style/AppTheme.PopupOverlay"
app:theme="#style/ToolbarMenuItemsBackGroundTheme"
tools:targetApi="lollipop">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/title_txt"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_toStartOf="#+id/star_img"
android:ellipsize="end"
android:fontFamily="sans-serif-medium"
android:gravity="center_vertical"
android:maxLines="1"
android:textColor="#color/colorPrimaryDark"
android:textSize="19sp" />
<ImageView
android:id="#+id/star_img"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_centerInParent="true"
android:layout_gravity="center"
android:layout_marginEnd="24dp"
android:padding="10dp"
android:src="#drawable/ic_favorite_filled" />
</RelativeLayout>
</android.support.v7.widget.Toolbar>
<android.support.design.widget.TabLayout
android:id="#+id/tab_layout"
android:layout_width="wrap_content"
android:layout_height="48dp"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:background="#45b0b2"
android:visibility="gone"
app:tabBackground="#drawable/backgr_blue_transparent_selector"
app:tabGravity="center"
app:tabIndicatorColor="#color/colorPrimaryDark"
app:tabIndicatorHeight="2dp"
app:tabMinWidth="500dp"
app:tabMode="fixed"
app:tabSelectedTextColor="#color/colorPrimaryDark"
app:tabTextAppearance="#style/CustomTabLayout"
app:tabTextColor="#color/green" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<FrameLayout
android:id="#+id/fragment_content_holder"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/black"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<android.support.v4.view.ViewPager
android:id="#+id/view_pager_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="gone"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>

Try scrolling to top in the fragment in the view pager by calling scrollView.fullScroll(View.FOCUS_UP) whenever you click on a tab. If your fragment inside the viewpager is scrolled up then your scrolling should work correctly.

You have done it almost correctly. But need some minor tweaks and modifications.
Step 1 : Set some height to your appBar. Say 224dp.
Step 2 : Set match_parent property to CollapsingToolbarLayout height.
Step 3 : Set following scroll flags to the CollapsingToolbarLayout
`app:layout_scrollFlags = "scroll|enterAlways|enterAlwaysCollapsed"`
Step 4 : Set the toolbar collapsemode to none
Check if it works fine. Let me know.

I have spend a lot of time investigating my issue with AppBar + Collapsing Layouts. And what I did find out is that it's a bug in google support library. So I created the issue for google and they assigned it to one of developers: https://issuetracker.google.com/issues/78686882
But to solve this issue right now I made a workaround - if users will get stuck with scrolling on collapsing part of the layout - they will probably try to click on one of tabs in my TabLayout. So I added code to auto collapse with animation collapsing part of layout: appBarLayout.setExpanded(false, true);
Here is the code:
tabLayout.addOnTabSelectedListener(new ViewPagerOnTabSelectedListener(viewPagerLayout) {
#Override
public void onTabSelected(TabLayout.Tab tab) {
appBarLayout.setExpanded(false, true);
}
#Override
public void onTabUnselected(TabLayout.Tab tab) {
//no ui effects
}
#Override
public void onTabReselected(TabLayout.Tab tab) {
appBarLayout.setExpanded(false, true);
}
});

To solve this issue, there is a workaround to do on the AppBarLayout :
class CustomAppBarLayout #JvmOverloads constructor(
context: Context,
attrs: AttributeSet? = null,
defStyleAttr: Int = 0
) : AppBarLayout(context, attrs, defStyleAttr) {
override fun getBehavior(): CoordinatorLayout.Behavior<AppBarLayout> {
return Behavior().also {
it.setDragCallback(object : Behavior.DragCallback() {
override fun canDrag(appBarLayout: AppBarLayout) = true
})
}
}
}
Found here : https://github.com/material-components/material-components-android/issues/1878

Recyclerview in Coordinatorlayout cutting off last item

I have a Bottom Navigation Bar, and a frame layout which is the fragment container. So when a an icon on a Bottom Navigation Bar is clicked, the fragment above changes.
In one of the fragment, I have a coordinator layout, collapsing toolbar, and recycler view. At the moment, the data is just a dummy data.
The problem that I am encountering is that whenever that fragment is inflated for the first time, the Recyclerview works fine and shows all of the items in the list. But when I change the fragment and come back to this fragment again, the last item of the Recyclerview is being cut off and is being hidden behind the Bottom Navigation Bar.
Here is my code for activity_home_screen.xml
<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="com.smartinc.livesportstv.activities.HomeScreen">
<android.support.design.widget.BottomNavigationView
android:id="#+id/bottom_nav"
android:layout_width="match_parent"
android:layout_height="55dp"
android:layout_alignParentBottom="true"
android:layout_gravity="bottom"
app:itemBackground="?attr/colorPrimary"
app:itemIconTint="#drawable/selector_bottombar_item"
app:itemTextColor="#drawable/selector_bottombar_item"
app:menu="#menu/bottombar_menu" />
<FrameLayout
android:id="#+id/frame_fragmentholder"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#id/bottom_nav"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
/>
Here is the fragment_events.xml
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:fitsSystemWindows="true"
android:id="#+id/coordinator">
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar"
android:layout_width="match_parent"
android:layout_height="120dp"
>
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:contentScrim="#color/colorPrimary"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:title="Events"
app:expandedTitleTextAppearance="#style/TransparentText"
app:collapsedTitleTextAppearance="#style/Toolbar_text_black"
app:collapsedTitleGravity="center_horizontal"
android:paddingEnd="20dp"
android:fitsSystemWindows="true"
>
<!-- You can add views that you want to appear on the
collapsing toolbar here -->
<TextView
android:id="#+id/events_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Events"
android:textSize="30sp"
android:textColor="#color/black"
android:layout_marginTop="30dp"
android:layout_marginStart="20dp"
android:textStyle="bold"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="29 March, Thursday"
android:textSize="20sp"
android:textColor="#color/grey_800"
android:layout_marginTop="70dp"
android:layout_marginStart="20dp"
/>
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
android:minHeight="?attr/actionBarSize"
app:layout_scrollFlags="scroll|enterAlways"
android:gravity="center_horizontal"
app:popupTheme="#style/AppTheme"
app:contentInsetLeft="0dp"
app:contentInsetStart="0dp"
/>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view_events"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Request"
android:textSize="17sp"
android:layout_gravity="end"
android:textColor="#color/colorPrimaryDark"
android:padding="10dp"
android:layout_marginEnd="10dp"
android:layout_marginTop="5dp"
/>
Here is HomeScreen.java
public class HomeScreen extends AppCompatActivity {
private BottomNavigationView bottomNavigationView;
private String fragName = "";
#Override
public void startActivity(Intent intent) {
super.startActivity(intent);
Constants.overridePendingTransitionEnter(this);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home_screen);
init();
setMainFragment();
setBottomNavigation();
}
private void init(){
bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottom_nav);
}
private void setBottomNavigation(){
bottomNavigationView.setOnNavigationItemSelectedListener(
new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.bottombaritem_events:
if(!fragName.equals("events")) {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.setCustomAnimations(R.anim.left_slide_in, R.anim.right_slide_out);
ft.replace(R.id.frame_fragmentholder, new EventsFragment());
ft.commit();
fragName = "events";
}
return true;
case R.id.bottombaritem_channels:
FragmentTransaction ft2 = getSupportFragmentManager().beginTransaction();
if(fragName.equals("events")) {
ft2.setCustomAnimations(R.anim.right_slide_in, R.anim.left_slide_out);
} else {
ft2.setCustomAnimations(R.anim.left_slide_in, R.anim.right_slide_out);
}
ft2.replace(R.id.frame_fragmentholder, new ChannelsFragment());
ft2.commit();
fragName = "channels";
return true;
case R.id.bottombaritem_more:
if(!fragName.equals("more")) {
FragmentTransaction ft3 = getSupportFragmentManager().beginTransaction();
ft3.setCustomAnimations(R.anim.right_slide_in, R.anim.left_slide_out);
ft3.replace(R.id.frame_fragmentholder, new MoreFragment());
ft3.commit();
fragName = "more";
}
return true;
}
return false;
}
});
}
private void setMainFragment(){
fragName = "events";
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.frame_fragmentholder, new EventsFragment());
ft.commit();
}
#Override
public void onBackPressed() {
super.onBackPressed();
Constants.overridePendingTransitionExit(this);
}
}
And here is EventsFragment.java
public class EventsFragment extends Fragment {
private RecyclerView mRecyclerView;
private ArrayList<String> mData;
private CollapsingToolbarLayout collapsing_toolbar;
private Context mContext;
public EventsFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_events, container, false);
mContext = getActivity();
final CollapsingToolbarLayout collapsingToolbarLayout = (CollapsingToolbarLayout) view.findViewById(R.id.collapsing_toolbar);
AppBarLayout appBarLayout = (AppBarLayout) view.findViewById(R.id.app_bar);
appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
boolean isShow = true;
int scrollRange = -1;
#Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
if (scrollRange == -1) {
scrollRange = appBarLayout.getTotalScrollRange();
}
if (scrollRange + verticalOffset == 0) {
collapsingToolbarLayout.setTitle("Events");
isShow = true;
} else if(isShow) {
collapsingToolbarLayout.setTitle(" ");//carefull there should a space between double quote otherwise it wont work
isShow = false;
}
}
});
// Initialize the RecyclerView
mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_view_events);
setUpRecyclerView();
return view;
}
private void setUpRecyclerView() {
LinearLayoutManager llm = new LinearLayoutManager(mContext);
llm.setAutoMeasureEnabled(true);
mRecyclerView.setLayoutManager(llm);
EventsAdapter eventsAdapter = new EventsAdapter(mContext);
mRecyclerView.setAdapter(eventsAdapter);
}
}
Any help would be really appreciated. Thanks!

Remove this line from Event XML.
android:fitsSystemWindows="true"
And everything would be good to go.

override the fragment's setUserVisibleHint(),call view?.requestlayout()
override fun setUserVisibleHint(isVisibleToUser: Boolean) {
view?.requestLayout()
super.setUserVisibleHint(isVisibleToUser)
}

collapsingToolbarLayout.setTitle("Events");
this layout is hiding your last Recycler view, when this is shown your last item is hidden, when you set
collapsingToolbarLayout.setTitle("");
your last item is visible.
So, set padding to parent layout accordingly

Content not shown in Fragment TabLayout Android

I have spent the whole day trying to fix this but I couldn't.
In my android application, I have a mainActivity HomePageServices, which has 3 tabs : HomeActivity, ProfileActivity, and SettingsActivity.
These tabs are Fragments called by TabLayout and ViewPager.
The transition between tabs works perfectly, but the problem is I have nothing displayed in any of the fragments!
I want to dispaly a RecyclerView with a GridLayout of cards in HomeActivity.
Here is what I have done so far:
HomePageServices:
public class HomePageServices extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ActionBar actionBar = getSupportActionBar();
actionBar.hide();
//Toolbar
initCollapsingToolbar();
//tabs
TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);
tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);
final ViewPager viewPager = (ViewPager) findViewById(R.id.pager);
final PagerAdapter adapter = new PagerAdapter
(getSupportFragmentManager(), tabLayout.getTabCount());
viewPager.setAdapter(adapter);
viewPager.addOnPageChangeListener(new
TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
#Override
public void onTabSelected(TabLayout.Tab tab) {
viewPager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(TabLayout.Tab tab) {
}
#Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
/**
* Initializing collapsing toolbar
* Will show and hide the toolbar title on scroll
*/
private void initCollapsingToolbar() {
final CollapsingToolbarLayout collapsingToolbar =
(CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
collapsingToolbar.setTitle(" ");
AppBarLayout appBarLayout = (AppBarLayout) findViewById(R.id.appbar);
appBarLayout.setExpanded(true);
// hiding & showing the title when toolbar expanded & collapsed
appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
boolean isShow = false;
int scrollRange = -1;
#Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
if (scrollRange == -1) {
scrollRange = appBarLayout.getTotalScrollRange();
}
if (scrollRange + verticalOffset == 0) {
collapsingToolbar.setTitle(getString(R.string.app_name));
isShow = true;
} else if (isShow) {
collapsingToolbar.setTitle(" ");
isShow = false;
}
}
});
}
}
HomePageServices XML layout:
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/white"
android:fitsSystemWindows="true"
>
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar"
android:layout_width="match_parent"
android:layout_height="#dimen/detail_backdrop_height"
android:fitsSystemWindows="true"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleMarginEnd="64dp"
app:expandedTitleMarginStart="48dp"
app:expandedTitleTextAppearance="#android:color/transparent"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageView
android:id="#+id/backdrop"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
android:scaleType="centerCrop"
app:layout_collapseMode="parallax"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
<TextView
android:id="#+id/love_music"
android:layout_width="237dp"
android:layout_height="wrap_content"
android:text="#string/backdrop_title"
android:textColor="#android:color/white"
android:textSize="#dimen/backdrop_title"
android:gravity="center_horizontal|center"
android:layout_gravity="center_horizontal|center"
android:layout_centerHorizontal="true" />
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
android:layout_centerVertical="true">
<android.support.design.widget.TabLayout
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:id="#+id/tab_layout">
<android.support.design.widget.TabItem
android:icon="#drawable/ic_home_white_24dp"
android:layout_height="match_parent"
android:layout_width="match_parent"/>
<android.support.design.widget.TabItem
android:icon="#drawable/ic_perm_identity_white_24dp"
android:layout_height="match_parent"
android:layout_width="match_parent"/>
<android.support.design.widget.TabItem
android:icon="#drawable/ic_settings_white_24dp"
android:layout_height="match_parent"
android:layout_width="match_parent"/>
</android.support.design.widget.TabLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:layout_below="#id/tab_layout"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.v7.widget.Toolbar>
</RelativeLayout>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
</android.support.design.widget.CoordinatorLayout>
PagerAdapter:
public class PagerAdapter extends FragmentStatePagerAdapter {
int mNumOfTabs;
public PagerAdapter(FragmentManager fm, int NumOfTabs) {
super(fm);
this.mNumOfTabs = NumOfTabs;
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
ProfileActivity tab1 = new ProfileActivity();
return tab1;
case 1:
SettingsActivity tab2 = new SettingsActivity();
return tab2;
case 2:
HomeActivity tab3=new HomeActivity();
return tab3;
default:
return null;
}
}
#Override
public int getCount() {
return mNumOfTabs;
}
}
HomeActivity
public class HomeActivity extends Fragment {
private RecyclerView recyclerView;
public static ServicesAdapter homeAdapter;
public static List<Service> serviceList;
final static String ADD_NEW_ITEM_TYPE="add new item";
public HomeActivity () {
//empty constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
//cards
View rootView=inflater.inflate(R.layout.activity_home2, container, false);
TextView tt= (TextView) rootView.findViewById(R.id.textView3);
recyclerView = (RecyclerView) rootView.findViewById(R.id.recycler_view);
serviceList = new ArrayList<>();
homeAdapter = new ServicesAdapter(this.getContext(), serviceList);
RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(getActivity(), 2);
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.addItemDecoration(new GridSpacingItemDecoration(2, dpToPx(10), true));
recyclerView.setItemAnimator(new DefaultItemAnimator());
initServices();
recyclerView.setAdapter(homeAdapter);
Log.d("show me what you got", serviceList.toString());
Toast.makeText(this.getContext(),"Hiiiiiiiiiiiiiiii from the other side",Toast.LENGTH_SHORT).show();
return rootView;
}
public static class GridSpacingItemDecoration extends RecyclerView.ItemDecoration {
int spanCount;
int spacing;
boolean includeEdge;
public GridSpacingItemDecoration(int spanCount, int spacing, boolean includeEdge) {
this.spanCount = spanCount;
this.spacing = spacing;
this.includeEdge = includeEdge;
}
}
private int dpToPx(int dp) {
Resources r = getResources();
return Math.round(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, r.getDisplayMetrics()));
}
public void initServices () {
Service a = new Service(ADD_NEW_ITEM_TYPE);
serviceList.add(a);
//just for testing
a = new Service("Signaler a dysfonctionnement");
serviceList.add(a);
a = new Service("Activités inter-employés");
serviceList.add(a);
homeAdapter.notifyDataSetChanged();
}
}
HomeActivity XML layout:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_home2"
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="HomeActivity">
<include layout="#layout/content_main"
/>
<TextView
android:text="TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_alignParentStart="true"
android:layout_marginStart="42dp"
android:id="#+id/textView3" />
</RelativeLayout>
And finally the RecyclerView layout:
<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"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="HomePage.HomeActivity"
tools:showIn="#layout/activity_home2">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clipToPadding="false"
android:scrollbars="vertical"
android:paddingLeft="5dp" />
</RelativeLayout>
PS: Before creating the tabs, the RecyclerViewer successfully displayed the cards in an Activity without any problems.

Scrolling in Fragment doesn't work into a TabLayout

I am stuck with scrolling in a fragment into a tablayout.
This is my MainActivity class
public class Mainctivity extends AppCompatActivity {
private TabLayout tabLayout;
private ViewPager viewPager;
ViewPagerAdapter viewPagerAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager();
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setViewPager(TabLayout.GRAVITY_FILL);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager() {
viewPagerAdapter = new ViewPagerAdapter(getSupportFragmentManager());
String [] tabNames = new String[{"Technology","World","Life"} ;
int [] tabTopicIds = new int[]{1,2,3} ;
for(int i=0; i< 7; i++)
{
OneFragment homeFeed = new OneFragment();
Bundle homeArgs = new Bundle();
homeArgs.putString("PAGE_NUMBER",""+tabTopicIds[i]);
homeFeed.setArguments(homeArgs);
viewPagerAdapter.addFragment(homeFeed, tabNames[i]); // note: this line can cause crashes
}
viewPager.setAdapter(viewPagerAdapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>(); // note: this line can cause crashes
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
}
And here is My activity_main layout.
<?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:layout_width="match_parent"
android:layout_height="match_parent"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#color/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light" />
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="48dip"
android:background="#color/white"
app:tabIndicatorColor="#color/colorPrimary"
app:pstsIndicatorHeight="3dip"
app:pstsTextAllCaps="false"
app:tabPaddingStart="2dp"
app:tabPaddingEnd="2dp"
app:tabGravity="fill"/>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.AppBarLayout>
</android.support.design.widget.CoordinatorLayout>
For each tab there is a FragmentOne class associated with viewPager and this is onCreateView Method of FragmentOne
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View mainView = inflater.inflate(R.layout.activity_main, container, false);
listView = (ListView) mainView.findViewById(R.id.list);
feedItems = new ArrayList<FeedItem>();
listAdapter = new FeedListAdapter(getActivity(), feedItems);
listView.setAdapter(listAdapter);
listView.setOnScrollListener(new EndlessScrollListener() {
#Override
public boolean onLoadMore(int page, int totalItemsCount) {
if(totalItemsCount > 150) return false;
return true;
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
if(!isLoading && firstVisibleItem + visibleItemCount >= totalItemCount && totalItemCount<MAX_ITEM_IN_LIST){
requestToServer(); // request for next items
}
}
});
return mainView;
}
Layout of FragmentOne
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/swipe_refresh_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ListView
android:id="#+id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:divider="#android:color/darker_gray"
android:background="#color/white"
android:dividerHeight="1.0sp"/>
</LinearLayout>
Here I add listView.setOnScrollListener into ListView of FragmentOne but doesn't work scrolling.
But when I FragmentOne put in another Layout like LinearLayout except Tablayout, it works fine.

You have put the viewpager code inside AppBarLayout in activity_main.xml. Cut and Paste the ViewPager outside AppBarLayout. Copy this code in your activity_main.xml. Hope it solves your problem.
<?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:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#color/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light" />
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/white"
app:tabIndicatorColor="#color/colorPrimary"
app:pstsIndicatorHeight="3dip"
app:pstsTextAllCaps="false"
app:tabPaddingStart="2dp"
app:tabPaddingEnd="2dp"
app:tabGravity="fill"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>

Moving FloatingActionButton when scrolling up CollapsingToolbarLayout

I have a layout with CollapsingToolbarLayout, a RecyclerView and a FloactingActionButton.
The idea is expand my Toolbar when the user is scrolling RecyclerView down and retracting it when scrolling up.
But when I scroll up my RecyclerView, the AppBarLayout retracts and my FloactingActionButton disappears.
I want to show it again in some other place in my screen like the botton.
How can I do It?
This is my screen:
Before Scrolling down - My FloactingActionButton is there.
After scrolling down - There's no room left for FloactingActionButton, so it dismiss. I just want to show it on botton of screen.
Code of my Layout XML :
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar_layout"
android:layout_width="match_parent"
android:layout_height="192dp">
<android.support.design.widget.CollapsingToolbarLayout
android:elevation="4dp"
android:id="#+id/collapsing_toolbar"
android:background="#color/primary"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<android.support.design.widget.FloatingActionButton
style="#style/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="true"
app:layout_anchor="#id/app_bar_layout"
app:layout_anchorGravity="bottom|right|end" />
Code of my Activity
public class MainActivityRecycler extends AppCompatActivity implements OnDataSelected {
private CollapsingToolbarLayout collapsingToolbarLayout;
public void onDataSelected(View view, int position) {
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_recycler);
setSupportActionBar((Toolbar) findViewById(R.id.toolbar));
collapsingToolbarLayout = (CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
collapsingToolbarLayout.setTitle("Collapsing");
//collapsingToolbarLayout.setExpandedTitleColor(getResources().getColor(android.R.color.transparent));
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
ArrayList<String> details = new ArrayList<String>();
details.add("Main Facilities");
details.add("Restaurants");
details.add("Shops");
details.add("Motel");
details.add("Forecourt");
DetailsAdapter mAdapter = new DetailsAdapter(this, null, details);
recyclerView.setAdapter(mAdapter);
recyclerView.setItemAnimator(new DefaultItemAnimator());
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
class DetailsAdapter extends RecyclerView.Adapter<DetailsAdapter.ViewHolder> {
private List<String> cars;
private Context context;
private OnDataSelected onDataSelected;
public DetailsAdapter(Context context, OnDataSelected onDataSelected, List<String> cars) {
this.context = context;
this.onDataSelected = onDataSelected;
this.cars = cars;
}
#Override
public DetailsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_layout, parent, false);
ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
String car = cars.get(position);
holder.textViewTitleCar.setText(car);
}
#Override
public int getItemCount() {
return cars.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView textViewTitleCar;
public ViewHolder(View view) {
super(view);
view.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
treatOnDataSelectedIfNecessary(v, getAdapterPosition());
}
});
textViewTitleCar = (TextView) view.findViewById(R.id.info_text);
}
}
private void treatOnDataSelectedIfNecessary(View view, int position) {
if (onDataSelected != null) {
onDataSelected.onDataSelected(view, position);
}
}
}
}

You can easily create any behavior for your item. You will need to realize ScrollListener for your AppBarLayout. More example of custom behavoir - Github
I hope correctly understood and helped.
public class FlexibleSpaceExampleActivity extends AppCompatActivity
implements AppBarLayout.OnOffsetChangedListener {
private static final int PERCENTAGE_TO_SHOW_IMAGE = 20;
private View mFab;
private int mMaxScrollSize;
private boolean mIsImageHidden;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_flexible_space);
mFab = findViewById(R.id.flexible_example_fab);
Toolbar toolbar = (Toolbar) findViewById(R.id.flexible_example_toolbar);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override public void onClick(View v) {
onBackPressed();
}
});
AppBarLayout appbar = (AppBarLayout) findViewById(R.id.flexible_example_appbar);
appbar.addOnOffsetChangedListener(this);
}
#Override
public void onOffsetChanged(AppBarLayout appBarLayout, int i) {
if (mMaxScrollSize == 0)
mMaxScrollSize = appBarLayout.getTotalScrollRange();
int currentScrollPercentage = (Math.abs(i)) * 100
/ mMaxScrollSize;
if (currentScrollPercentage >= PERCENTAGE_TO_SHOW_IMAGE) {
if (!mIsImageHidden) {
mIsImageHidden = true;
ViewCompat.animate(mFab).scaleY(0).scaleX(0).start();
/**
* Realize your any behavior for FAB here!
**/
}
}
if (currentScrollPercentage < PERCENTAGE_TO_SHOW_IMAGE) {
if (mIsImageHidden) {
mIsImageHidden = false;
ViewCompat.animate(mFab).scaleY(1).scaleX(1).start();
/**
* Realize your any behavior for FAB here!
**/
}
}
}
public static void start(Context c) {
c.startActivity(new Intent(c, FlexibleSpaceExampleActivity.class));
}
}

Use Floating Action Button and set property as I have set. It is very easy to display FAB in collapsingToolbarLayout.
<android.support.design.widget.AppBarLayout
android:id="#+id/activity_main_appbar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
tools:ignore="InconsistentLayout">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/activity_main_collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#2196f3"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
tools:ignore="InconsistentLayout">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/paris"
android:scaleType="centerCrop"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="#+id/activity_main_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#android:color/transparent"
app:layout_collapseMode="pin"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
</android.support.v7.widget.Toolbar>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
android:id="#+id/activity_main_nested_scroll_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:ignore="InconsistentLayout">
<android.support.v7.widget.RecyclerView
android:id="#+id/activity_main_recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.v4.widget.NestedScrollView>
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="20dp"
android:src="#drawable/ic_call_black_24dp"
app:layout_anchor="#id/activity_main_appbar"
app:layout_anchorGravity="bottom|right|end" />