Develop Reference

Put a view on top of AppBarLayout

I am working on a UI that utilizes the CoordinatorLayout/AppBarLayout combo as normally seen in most examples but there is this requirement of mine: I want to overlay the AppBarLayout with a View at all times. So, whatever scrolling behavior that happens, should happen under this view. Currently, this is what I am seeing:
Here, the blue bar that you see is the one that I want on top of everything. As you can see, it is hidden initially and only gets exposed when we have scrolled AppBarLayout off the screen. For your reference, here is the code for this layout and its id is android:id="#+id/linearLayout":
<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.snapsboardmainpage.MainActivity"
tools:layout_editor_absoluteX="8dp"
tools:layout_editor_absoluteY="8dp">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:id="#+id/linearLayout3"
android:layout_width="match_parent"
android:layout_height="40dp"
app:layout_scrollFlags="scroll|snap"
android:orientation="vertical">
</LinearLayout>
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="112dp"
android:orientation="vertical"
app:layout_scrollFlags="scroll|snap"
android:background="#android:color/holo_green_light">
</LinearLayout>
<android.support.design.widget.TabLayout
android:id="#+id/id_tab_photosvideos_albums"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_scrollFlags="scroll|snap">
<android.support.design.widget.TabItem
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<android.support.design.widget.TabItem
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</android.support.design.widget.TabLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
android:id="#+id/nested_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<android.support.v4.view.ViewPager
android:id="#+id/id_viewpager_photosvideos_albums"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v4.view.ViewPager>
</android.support.v4.widget.NestedScrollView>
<LinearLayout
android:id="#+id/linearLayout"
android:layout_width="match_parent"
android:layout_height="40dp"
android:orientation="vertical"
android:layout_gravity="top"
app:layout_behavior="com.example.snapsboardmainpage.TopActionBarBehavior"
android:background="#android:color/holo_blue_light">
</LinearLayout>
<LinearLayout
android:id="#+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="56dp"
android:orientation="vertical"
android:layout_gravity="bottom"
android:background="#android:color/holo_orange_light">
</LinearLayout>
</android.support.design.widget.CoordinatorLayout>
How can I achieve this overlay behavior?(it would be preferable if this blue bar could remain as a direct child of CoordinatorLayout)

Although the question seems to be difficult, the solution turned out to be amazingly simple:
android:elevation="8dp"
Yes, that was it. Just set it on the the view that had to overlay the AppBarLayout.

android:elevation="8dp" work on API level 21.
So You can put your view in side a new AppBarLayout.
In my case , i put my xml code in to new AppBarLayout like below
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/root"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/black"
android:fitsSystemWindows="true"
android:orientation="vertical">
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/app_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay"
app:title="#string/app_name" />
<com.google.android.material.tabs.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</com.google.android.material.appbar.AppBarLayout>
<!--i want below view on the top of app bar layout of id(android:id="#+id/app_bar")
so i put my all view inside the new app bar layout of id(
android:id="#+id/longClickItem")-->
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/longClickItem"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay"
android:visibility="gone">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#color/colorPrimary"
android:paddingTop="#dimen/_5sdp"
android:paddingBottom="#dimen/_5sdp">
<ImageView
android:id="#+id/longItemBack"
android:layout_width="#dimen/_25sdp"
android:layout_height="#dimen/_25sdp"
android:layout_centerVertical="true"
android:layout_marginStart="#dimen/_15sdp"
android:layout_marginEnd="#dimen/_15sdp"
android:src="#drawable/back_arrow" />
<TextView
android:id="#+id/longItemCount"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_toEndOf="#id/longItemBack"
android:text="0"
android:textColor="#android:color/white"
android:textSize="#dimen/_18sdp"
android:textStyle="bold" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_centerVertical="true">
<ImageView
android:id="#+id/longItemDelete"
style="#style/long_press_image_view"
android:src="#drawable/item_long_delete" />
</LinearLayout>
</RelativeLayout>
</com.google.android.material.appbar.AppBarLayout>
<androidx.viewpager.widget.ViewPager
android:id="#+id/viewPager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />

Touch event is not working for the ParentActivity

I've added appbarLayout and coordinatorLayout to both parent activity and it's child i.e fragment. At first, the touch event was hiding and showing toolbar of parent activity efficiently but when I used appbarlayout for the child fragment as well then the toolbar of a parent is not hiding while scrolling.
Can anyone suggest how to activate touch event for both simultaneously?
ParentActivity code:
<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:background="#fff"
android:focusable="true"
android:focusableInTouchMode="true"
android:fitsSystemWindows="true"
>
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#00ffffff"
>
<android.support.v7.widget.Toolbar
android:id="#+id/search_bar_settings_container"
android:layout_width="match_parent"
android:layout_height="48dp"
android:layout_marginStart="-15dp"
app:layout_scrollFlags="scroll|enterAlways"
>
<EditText
android:id="#+id/search_bar"
android:layout_marginTop="5dp"
android:layout_width="305sp"
android:layout_height="35dp"
android:hint=" Search Here..."
android:imeOptions="actionSearch"
android:singleLine="true"
android:paddingLeft="9dp"
android:paddingStart="9dp"
android:background="#drawable/society_style"/>
<ImageView
android:id="#+id/search_icon"
android:layout_width="35dp"
android:layout_height="38dp"
android:layout_marginTop="2dp"
android:src="#drawable/search"
/>
</android.support.v7.widget.Toolbar>
<android.support.design.widget.TabLayout
android:id="#+id/tabLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#001919"
android:minHeight="?attr/actionBarSize"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:tabIndicatorColor="#ffffff" />
</android.support.design.widget.AppBarLayout>
<!-- View pager to swipe views -->
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
Fragment Class's code:
<android.support.design.widget.CoordinatorLayout 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"
tools:context="layout.Society_Show"
>
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#00ffffff"
android:layout_marginStart="-13dp"
>
<android.support.v7.widget.Toolbar
android:id="#+id/society_show_container"
android:layout_width="match_parent"
android:layout_height="55dp"
app:layout_scrollFlags="scroll|enterAlways"
>
<LinearLayout
android:id="#+id/selected_society_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
>
<android.support.v7.widget.RecyclerView
android:id="#+id/selected_society"
android:layout_marginTop="2sp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
</android.support.v7.widget.Toolbar>
</android.support.design.widget.AppBarLayout>
<shivam.developer.featuredrecyclerview.FeaturedRecyclerView
android:id="#+id/featured_recycler_view_society"
android:layout_below="#+id/selected_society_layout"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:layout_marginTop="2sp"
app:defaultItemHeight="270dp"
app:featuredItemHeight="400dp"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
<ImageView
android:id="#+id/plus"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_gravity="end|bottom"
android:src="#drawable/new_add_one"
android:layout_marginRight="5dp"
android:layout_marginEnd="5dp"
android:layout_marginBottom="65dp"
/>

You should not define the AppBarLayout in your Fragment, but only in the Activity like this:
<android.support.design.widget.CoordinatorLayout
android:fitsSystemWindows="true"
android:id="#+id/coordinator_layout"
android:layout_height="match_parent"
android:layout_width="match_parent"
tools:context=".YourActivity">
<android.support.design.widget.AppBarLayout
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:background="?colorPrimary"
android:id="#+id/toolbar"
android:layout_height="?actionBarSize"
android:layout_width="match_parent"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/AppTheme.PopupOverlay"
app:theme="#style/ThemeOverlay.AppCompat.Dark" />
</android.support.design.widget.AppBarLayout>
<LinearLayout
android:background="#color/colorBackgroundTint"
android:id="#+id/pager_container"
android:layout_height="match_parent"
android:layout_width="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:showIn="#layout/activity_schedule">
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_height="match_parent"
android:layout_width="match_parent" />
</LinearLayout>
</android.support.design.widget.CoordinatorLayout>
Because, you only need one AppBar, since Fragments are part of an Activity.
Your ViewPager will include the Fragment whose layout will look like this:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- Your content e.g. RecyclerView -->
</RelativeLayout>
Android will capture your scrolling and hide the Toolbar.

Brilliant you're using appbarLayout in order to avoid the boilerplate code of adding one recycler view to another . It solved my tension of adding two recycler views together.
By the way I think you shouldn't use the appbarLayout for the parent activity try changing your design and add appbarLayout only to your fragment activity.

Avoid scrolling in bottom view inside ViewPager inside CoordinatorLayout

I have this structure in my main 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="wrap_content"
android:fitsSystemWindows="true"
tools:context="com.pingvalue.example.MainActivity">
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<include
android:id="#+id/linear_header"
layout="#layout/product_detail_header" />
<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:layout_width="match_parent"
android:layout_height="wrap_content"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>
and this is my layout that I'm using in a fragment inside ViewPager
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="6dp">
<EditText
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:drawableRight="#drawable/ic_insert_emoticon_black_24px"
android:gravity="center_vertical"
android:hint="#string/what_do_you_want_to_say"
android:textSize="16sp" />
<Button
android:layout_width="40dp"
android:layout_height="30dp"
android:layout_marginLeft="6dp"
android:background="#drawable/ic_send_selector"
android:enabled="false" />
</LinearLayout>
</LinearLayout>
I want to achieve the following behaviour. This is a screenshot when AppBarLayout is collapsed:
As you can see the layout with the EditText and Button is visible, but when I scroll up it disappears. I've try with a custom CoordinatorLayout behaviour but it doesn't work because it is not a direct child from my CoordinatorLayout. I've try also changing match_parent to wrap_content but it put empty space below the LinearLayout.

Put the LinearLayout with your EditText in it outside of the CoordinatorLayout and wrap everything in a LinearLayout.
<LinearLayout
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:orientation="vertical"
tools:context="com.pingvalue.example.MainActivity">
<android.support.design.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight=1>
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<include
android:id="#+id/linear_header"
layout="#layout/product_detail_header" />
<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:layout_width="match_parent"
android:layout_height="wrap_content"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="6dp">
<EditText
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:drawableRight="#drawable/ic_insert_emoticon_black_24px"
android:gravity="center_vertical"
android:hint="#string/what_do_you_want_to_say"
android:textSize="16sp" />
<Button
android:layout_width="40dp"
android:layout_height="30dp"
android:layout_marginLeft="6dp"
android:background="#drawable/ic_send_selector"
android:enabled="false" />
</LinearLayout>
</LinearLayout>
This should allow you to have your composer area always visible no matter how far you have scrolled the header.

Try with following layout
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="6dp"
android:layout_weight="0">
<EditText
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:drawableRight="#drawable/ic_insert_emoticon_black_24px"
android:gravity="center_vertical"
android:hint="#string/what_do_you_want_to_say"
android:textSize="16sp" />
<Button
android:layout_width="40dp"
android:layout_height="30dp"
android:layout_marginLeft="6dp"
android:background="#drawable/ic_send_selector"
android:enabled="false" />
</LinearLayout>
</LinearLayout>

I've tried also adding a NestedScrollView with no result

coordinate layout issue while loading in frameLayout

I am working on code that have FrameLayout and customview at bottom. I loaded a fragment inside FrameLayout, which is having CoordinatorLayout with ViewPager inside.
So problem is ViewPager takes full height of the phone and hide contents of list behind customview. Here is Code:
main_layout.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:fitsSystemWindows="true"
android:layout_height="match_parent">
<FrameLayout
android:id="#+id/root_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/playerView"
android:layout_alignParentTop="true" />
<TextView
android:id="#+id/playerView"
android:layout_width="match_parent"
android:layout_height="#dimen/player_size"
android:layout_alignParentBottom="true"
android:background="#D7D7D7"
android:gravity="center"
android:text="Player View"
android:textSize="20sp" />
</RelativeLayout>
fragment_view.xml
<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="wrap_content">
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar"
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="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light" />
<android.support.design.widget.TabLayout
android:id="#+id/tabs_view_tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_collapseMode="pin"
android:background="?attr/colorPrimary"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/tabs_view_viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
In above image you can see some content of list is hidden beside PlayerView.

Try to use LinearLayout with layout_weight instead of RelativeLayout inside main_layout.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:fitsSystemWindows="true"
android:layout_height="match_parent"
android:orientation="vertical">
<FrameLayout
android:id="#+id/root_content"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
<TextView
android:id="#+id/playerView"
android:layout_width="match_parent"
android:layout_height="#dimen/player_size"
android:background="#D7D7D7"
android:gravity="center"
android:text="Player View"
android:textSize="20sp" />
</LinearLayout>

Header layout above TabLayout

I'm trying to do something like this:
I currently have the above layout without the header implemented. All I need is to figure out how to add the header.
Here is the header layout I want to put above the tabs:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:id="#+id/header"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_gravity="center_horizontal"
android:background="#color/green">
<LinearLayout
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="match_parent" >
<ImageView
android:layout_width="50dp"
android:layout_height="50dp"
android:background="#drawable/ic_image"
android:adjustViewBounds="true"
android:scaleType="centerCrop"
android:layout_gravity="center_vertical" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hey!"
android:textColor="#color/white"
android:textSize="24sp"
android:layout_gravity="center_vertical" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
I use a RecyclerView for the content below the tabs. I use 3 different Fragments for the Activity.
Here is my Activity:
<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:id="#+id/appbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:elevation="0dp">
<android.support.v7.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/toolbar_group"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minHeight="0dp"
android:background="#color/blue"
app:layout_scrollFlags="scroll|enterAlways|enterAlwaysCollapsed"
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"
app:tabTextAppearance="#style/TabLayout"
app:tabSelectedTextColor="#color/white"
app:tabTextColor="#color/white"
/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
/>
</android.support.design.widget.CoordinatorLayout>
And here is one of my Fragments:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:scrollbars="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</android.support.design.widget.CoordinatorLayout>
How can I add the header above the TabLayout and keep normal scrolling behaviors?

You just need a RecyclerView to do that.
Combine your header and tabLayout to a Header view, then add to your RecyclerView.
Check https://github.com/u3breeze/android-RecyclerView-WithHeaderAndFooter. I did a extension of RecyclerView.Adapter. Easy to add header and footer to RecyclerView.