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hide toolbar and keep tapLaout when scroll in using viewPager [duplicate]

This question already has answers here:
Hiding/Showing the toolbar when fragment in the tabs is scrolled
(8 answers)
Closed 1 year ago.
I need to hide toolBar(Header) and keep tapLayout in the top when scroll viewPager
viewPager will contain fragment contain a RecyclerView
tell me if there is another way to code it
if there is a way to fix this code this is the best for me
My layout design
Here is my XML code
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.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">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true">
<com.google.android.material.appbar.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:contentScrim="#color/white"
app:layout_collapseMode="parallax"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<include
android:id="#+id/homeHeader"
layout="#layout/user_profile_header" />
</com.google.android.material.appbar.CollapsingToolbarLayout>
</com.google.android.material.appbar.AppBarLayout>
<LinearLayout
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<!--Tab-->
<com.google.android.material.tabs.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabGravity="fill"
app:tabMode="fixed" />
<!--ViewPager-->
<androidx.viewpager.widget.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
</androidx.coordinatorlayout.widget.CoordinatorLayout>

getSupportActionBar().hide();
Place this part of code in your oncreate

View pager is overlapping the tab fragments vertically

I am using Viewpager to browse through the tabs. But my viewpager is overlapping the top of the fragment due to which the top of all the fagments are not visible. Adding padding on the top does the work but is there any better way to do it rather than giving padding on the next view.
Layout
<?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"
tools:context=".Activity.MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.TabLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/tabs">
</android.support.design.widget.TabLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:background="#ffffff">
</android.support.v4.view.ViewPager>
</RelativeLayout>
Activity
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ActionBar
final ActionBar actionBar = getSupportActionBar();
actionBar.setDefaultDisplayHomeAsUpEnabled(true);
// ViewPage: Slider that helps to create a page that we can swipe
PagerAdapter pagerAdapter = new TabPagerAdapter(getSupportFragmentManager());
ViewPager tab = (ViewPager) findViewById(R.id.pager);
tab.setAdapter(pagerAdapter);
//Tablayout : Shows the tab bar that helps to find the ViewPager page
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(tab);
}

Hope this can help you..
<LinearLayout 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:orientation="vertical">
<android.support.design.widget.CoordinatorLayout
android:id="#+id/coordinator"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/ThemeOverlay.AppCompat.Dark">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways" />
<android.support.design.widget.TabLayout
android:id="#+id/tablayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="?attr/colorPrimary"
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="wrap_content"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>

You have used Relative Layout and not defined android:layout_below="#id/appbar_layout" . So I have edited your code. Just copy and paste below code in your xml file. It'll solve your problem.
<?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.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/appbar_layout"
android:fitsSystemWindows="true"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.TabLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/tabs">
</android.support.design.widget.TabLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/appbar_layout"
android:orientation="vertical"
android:background="#ffffff">
</android.support.v4.view.ViewPager>
</RelativeLayout>

How to put RecyclerView below Toolbar and above TabLayout and ViewPager also handling responses to scrolls in a custom manner?

I want to create a layout like the below image:
A CoordinatorLayout which contain :
CollapsingToolbarLayout( contain ImageView & Toolbar)
RecyclerView
TabLayout
ViewPager( that each fragment of it contain a RecyclerView)
I wanna responding to scroll events in this way:
CollapsingToolbarLayout expand and collapse by scrolling
Toolbar sticks to the top until TabLayout reach to the top
After that toolbar scroll up and TabLayout stick to the top
I'm having trouble with the RecyclerView between CollapsingToolbarLayout and TabLayout. I can implement this layout without that RecyclerView( I put CollapsingToolbarLayout and TabLayout inside the AppBarLayout and the ViewPager outside it, inside the CoordinatorLayout).
My Question:
Where should I put that RecyclerView?
Which & where layout_scrollFlags and layout_behavior should I set for each layouts?
It seems that AppBarLayout have a limited height. When I put the RecyclerView inside AppBarLayout, only a portion part of the RecyclerView is visible and also TabLayout disappear.
I read lots of tutorials like this one and lots of questions like this one and this one, but non of them help me.

use this as a main layout
activity_main
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.SwipeRefreshLayout 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/swipe_refresh_layout_profile"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:ignore="RtlHardcoded">
<android.support.design.widget.CoordinatorLayout
android:id="#+id/co_profile_activity_root_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/white"
android:visibility="visible">
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar_profile"
android:layout_width="match_parent"
android:layout_height="#dimen/profile_img_placeholder_height"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapse_toolbar_profile"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_scrollFlags="scroll|exitUntilCollapsed|snap">
<RelativeLayout
android:id="#+id/rel_top"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop">
<ImageView
android:id="#+id/img_bg_placeholder_profile"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:tint="#11000000"
app:layout_collapseMode="parallax"
app:layout_collapseParallaxMultiplier="0.9" />
<LinearLayout
android:id="#+id/lin_top_inner"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#BF473e6b"
android:orientation="vertical"
android:scaleType="centerCrop">
</LinearLayout>
</RelativeLayout>
<FrameLayout
android:id="#+id/frame_detail_profile"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center|center_horizontal"
android:orientation="vertical"
app:layout_collapseMode="parallax"
app:layout_collapseParallaxMultiplier="0.3">
<android.support.v7.widget.RecyclerView
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</android.support.v7.widget.RecyclerView>
</FrameLayout>
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar_profile"
android:layout_width="match_parent"
android:layout_height="#dimen/profile_toolbar_height"
android:gravity="top|center"
app:layout_anchor="#id/frame_detail_profile"
app:layout_collapseMode="pin"
app:theme="#style/ThemeOverlay.AppCompat.Dark"
app:title="">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/tv_toolbar_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="#dimen/profile_toolbar_title_left_margin"
android:gravity="center_vertical|center"
android:ellipsize="end"
android:singleLine="true"
android:layout_gravity="center"
android:textColor="#android:color/white"
android:textSize="20sp" />
</LinearLayout>
</android.support.v7.widget.Toolbar>
<android.support.design.widget.TabLayout
android:id="#+id/tab_layout_profile"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:layout_gravity="bottom"
android:layout_marginTop="#dimen/profile_tab_layout_top_margin"
android:background="#color/white"
app:tabIndicatorColor="#color/colorPrimary"
app:tabSelectedTextColor="#color/colorPrimary"
app:tabTextColor="#color/charcoal_grey" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/view_pager_profile"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
</RelativeLayout>
</android.support.v4.widget.SwipeRefreshLayout>
and for grid layout of tabs use adapter classes.

Start with AppBarLayout under which you add CollapsingToolbarLayout with scrollFlags="scroll|exitUntilCollapsed",
add LinearLayout with vertical orientation to CollapsingToolbarLayout and add the
FrameLayout with ImageView + Toolbar
RecyclerView
TabLayout

Two things to be done:-
When the search button is clicked, set the visibility of recycler view to VISIBLE
When the back button is pressed, set the visibility of recycler view to GONE
Following are the implementations:
1. Setting the visibility of recycler view to VISIBLE:
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == R.id.searchView) {
rView.setVisibility(VISIBLE);
}
return true;
}
2. Setting the visibility of recycle adapter to GONE
MenuItem searchMenuItem = menu.findItem(R.id.searchView);
MenuItemCompat.setOnActionExpandListener(searchMenuItem, new MenuItemCompat.OnActionExpandListener() {
#Override
public boolean onMenuItemActionExpand(MenuItem item) {
return true;
}
#Override
public boolean onMenuItemActionCollapse(MenuItem item) {
recyclerView.setVisibility(GONE);
return true;
}
});
NOTE: Do not forget to keep the visibilty as GONE initially when the activity is started

I know I might be late to this answer but I have also been trying to implement this for a while. The solution I have feels a bit hacky but it is an option for trying to get the tabs to stick. In a simpler solution lets say we wanted the following:
A Collapsing toolbar layout
Which links to a scroll view.
In that scroll view we want the following:
A recyclerview that say scrolls horizontally
Below the recycler view a tab layout
Below the tab layout we want a view pager that will load dynamic fragments within a fixed space.
activity_scrolling.xml the outer parent xml file may look something like this
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.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"
tools:context=".temp.ScrollingActivity">
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/app_bar"
android:layout_width="match_parent"
android:layout_height="#dimen/app_bar_height"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<com.google.android.material.appbar.CollapsingToolbarLayout
android:id="#+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:toolbarId="#+id/toolbar">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:layout_marginBottom="5dp"
app:layout_collapseMode="pin"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</com.google.android.material.appbar.CollapsingToolbarLayout>
</com.google.android.material.appbar.AppBarLayout>
<include layout="#layout/content_scrolling" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/fab_margin"
app:layout_anchor="#id/app_bar"
app:layout_anchorGravity="bottom|end"
app:srcCompat="#android:drawable/ic_dialog_email" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
Then the inner content_scrolling.xml may look something like this
<?xml version="1.0" encoding="utf-8"?>
<androidx.core.widget.NestedScrollView 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=".temp.ScrollingActivity"
tools:showIn="#layout/activity_scrolling">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="5dp"
android:layout_marginTop="20dp"
android:layout_marginEnd="20dp"
android:gravity="center"
android:text="A Heading"
android:textSize="#dimen/text_xl"
android:textStyle="bold" />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/title" />
<com.google.android.material.tabs.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/recycler_view"
android:layout_gravity="center"
android:minHeight="60dp"
app:tabGravity="fill"
app:tabIndicatorColor="#color/colorAccent"
app:tabMode="fixed"
app:tabSelectedTextColor="#color/colorPrimaryDark" />
<androidx.viewpager.widget.ViewPager
android:id="#+id/view_pager"
android:layout_width="match_parent"
android:layout_height="680dp"
android:layout_below="#+id/tabs" />
</RelativeLayout>
</androidx.core.widget.NestedScrollView>
This will allow you to forcefully place the tab layout in a location of your choosing (even if its after a recyler view).
The hacky part which i dont like is this specific line android:layout_height="680dp" which forces the viewpager height to be something specific. I am not sure why wrap_content or match_parent do not work. But this is the best thing to a solution I can provide for the issue of placing TabLayout and ViewPager in specific places.

Why is my Actionbar not moving up while scrolling?

I have an activity with a drawer layout and a toolbar is included as follows:
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<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">
<include
android:id="#+id/tool_bar"
layout="#layout/tool_bar"
>
</include>
<!-- The main content view -->
<FrameLayout
android:id="#+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.design.widget.AppBarLayout>
</android.support.design.widget.CoordinatorLayout>
<!-- The navigation drawer list-->
<android.support.v7.widget.RecyclerView
android:id="#+id/RecyclerView"
android:layout_width="280dp"
android:layout_height="match_parent"
android:layout_gravity="left"
android:background="#ffffff"
android:scrollbars="vertical">
</android.support.v7.widget.RecyclerView>
</android.support.v4.widget.DrawerLayout>
The toolbar looks like this:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="#color/background_floating_material_dark"
android:elevation="4dp"
android:paddingTop="1dp"
app:layout_scrollFlags="scroll|enterAlways">
</android.support.v7.widget.Toolbar>
To this activity I keep on adding/replacing fragments #id/frame_container
Now I have a situation where I have a fragment with 2 tabs, which in turn have recycler views fed to a view pager:
And I am setting it up in java as follows:
TabLayout tabLayout = (TabLayout) rootView.findViewById(R.id.tab_layout2);
tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);
viewPager = (ViewPager) rootView.findViewById(R.id.pager2);
adapter = new MyFragmentAdapter(
getFragmentManager(), 2);
viewPager.setAdapter(adapter);
tabLayout.setupWithViewPager(viewPager);
Layout of this Fragment:
<RelativeLayout ...
<android.support.design.widget.TabLayout
android:id="#+id/tab_layout2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="?attr/colorPrimary"
android:elevation="6dp"
android:minHeight="?attr/actionBarSize"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"/>
<android.support.v4.view.ViewPager
android:layout_marginTop="#dimen/abc_action_bar_stacked_max_height"
android:id="#+id/pager2"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:layout_below="#id/tab_layout"
/>
</RelativeLayout>
The fragments in the view pager have the recycler view.:
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/listViewPO"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_marginBottom="2px">
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
The problem is the action bar is not hiding when I try to scroll. I am not able to figure out the issue. I have spent days with this. Please help!

Toolbar not collapsing with TabLayout

I would like to let the Toolbar collapse when the user scrolls in one of the TabLayout's tabs (supplied by ViewPager).
This is the functionality I desire:
However, my layout does not only not scroll, but also cuts off content at the bottom (to be exact, it cuts off 48dp - the height of a toolbar):
I use the ViewPager to display each Fragment as a tab. The Fragments consist of a simple ScrollView holding a TextView. Here is the 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:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.Toolbar
android:id="#+id/ueber_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:layout_scrollFlags="scroll|enterAlways" />
<android.support.design.widget.TabLayout
android:id="#+id/ueber_tabLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="fixed"
app:tabGravity="fill"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:tabIndicatorColor="#android:color/white"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/ueber_viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>
Each fragment has the following layout:
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="#+id/ueber_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="14sp"
android:textColor="#000000"
android:linksClickable="false"
android:textColorLink="#000000"
android:fontFamily="serif"
android:padding="16dp"/>
</ScrollView>
The ViewPager is set up by a ViewPagerAdapter:
ViewPager viewPager = (ViewPager) findViewById(R.id.ueber_viewpager);
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFrag(new ContentFragment(), "Über");
adapter.addFrag(new ContentFragment(), "Impressum");
adapter.addFrag(new ContentFragment(), "Lizenzen");
viewPager.setAdapter(adapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.ueber_tabLayout);
tabLayout.setupWithViewPager(viewPager);

Use a NestedScrollView instead of a ScrollView.
<android.support.v4.widget.NestedScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">

When the user scrolls in to the fragment, hide the toolbar:
getSupportActionBar().hide();
When they scroll back to the top, show the toolbar:
getSupportActionBar().show();