Hiding/Showing the toolbar when fragment in the tabs is scrolled

Firstly, You should move your webview into NestedScrollView and set 'android:isScrollContainer' property to 'false' value. https://developer.android.com/reference/android/support/v4/widget/NestedScrollView.html

Secondly, You should move your ViewPager outside the AppBarLayout. So, your main.xml should be like this:

<?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/main_content"
android:background="#FFF"
android:clickable="true"
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">

    <!-- your app bar stuff here -->
    <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="240dp"
        app:layout_scrollFlags="scroll|enterAlways">

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scaleType="fitXY"
            android:id="@+id/image_header"/>

        <include layout="@layout/header"/>

    </FrameLayout>

    <android.support.design.widget.TabLayout
        android:id="@+id/tabs"
        android:background="#FFF"
        app:tabTextColor="#a3a3a3"
        app:tabSelectedTextColor="#a3a3a3"
        app:tabIndicatorColor="#0042ab"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        />

</android.support.design.widget.AppBarLayout>

<android.support.v4.view.ViewPager
    android:id="@+id/viewpager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:visibility="gone"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    android:background="#eaeaea"/>

AppBarLayout childern will hide only if they have flag app:layout_scrollFlags

Read more about implementing support design library here:
https://android-developers.googleblog.com/2015/05/android-design-support-library.html

You should move your ViewPager outside the AppBarLayout and add behavior to ViewPager app:layout_behavior="@string/appbar_scrolling_view_behavior"

I wrote a full example! https://github.com/erikcaffrey/AndroidDesignSupportLibrary

I hope it help you!

Try this.

main.xml

<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/coordinatorLayout"
    android:layout_height="match_parent"
    android:layout_width="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.support.v7.widget.Toolbar
            android:id="@+id/toolbarsdfs"
            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:scrollbars="horizontal"
            android:layout_below="@+id/toolbarsdfs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="?attr/colorPrimary"
            app:tabTextColor="@android:color/white"
            app:tabSelectedTextColor="@android:color/white"
            app:tabIndicatorColor="@android:color/white"
            app:tabIndicatorHeight="3dp" />

    </android.support.design.widget.AppBarLayout>
    <android.support.v4.view.ViewPager
        android:id="@+id/pager"
        android:layout_width="match_parent"
        android:layout_height="fill_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        android:layout_below="@+id/tablayout"/>
    </android.support.design.widget.CoordinatorLayout>

fragmentfeeds.xml

    <?xml version="1.0" encoding="utf-8"?>
    <android.support.v4.widget.NestedScrollView
            xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:app="http://schemas.android.com/apk/res-auto"
            android:isScrollContainer="false"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_gravity="fill_vertical"
            android:clipToPadding="false"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="vertical">

    <ProgressBar
            android:id="@+id/progressBar"
            style="?android:attr/progressBarStyleSmall"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <android.support.v4.widget.SwipeRefreshLayout
          xmlns:android="http://schemas.android.com/apk/res/android"
          android:id="@+id/swipe"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:background="#FFFFFF">     

    <WebView
             android:id="@+id/webviewtool"
             android:layout_width="match_parent"
             android:layout_height="fill_parent"
             android:numColumns="1"
             android:focusableInTouchMode="false"
             android:focusable="false"
             android:background="#FFFFFF" />
</android.support.v4.widget.SwipeRefreshLayout>
             </LinearLayout>
    </android.support.v4.widget.NestedScrollView>