title: Android alphabetical fast scrollview in RecyclerView with Collapsing toolbar
body: <p>In my application I have activity_main.xml like this:-</p>
  
  <pre><code>&lt;Coordinator Layout&gt;
     &lt;AppBarLayout&gt;
        &lt;CollapsingToolbarLayout&gt;
             &lt;ImageView/&gt;
             &lt;Toolbar/&gt;
         &lt;/CollapsingToolbarLayout&gt;
     &lt;/AppBarLayout&gt;
     &lt;RecyclerView/&gt;
  &lt;/Coordinating Layout&gt;
  </code></pre>
  
  <p>Layout.xml ----->>></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  
  
  
  &lt;android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      xmlns:ads="http://schemas.android.com/apk/res-auto"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:background="@drawable/theme_background"
      android:id="@+id/drawerlayout"
      &gt;
  
  
      &lt;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:id="@+id/activity_main_id"
          tools:context="objectdistance.ajai.ram.sita.gallery.MainActivity"&gt;
  
          &lt;android.support.design.widget.AppBarLayout
              android:id="@+id/app_bar_layout"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:fitsSystemWindows="true"
              android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"&gt;
  
  
              &lt;android.support.design.widget.CollapsingToolbarLayout
                  android:id="@+id/collapsing_toolbar"
                  android:layout_width="match_parent"
                  android:layout_height="match_parent"
                  app:layout_scrollFlags="scroll|exitUntilCollapsed"
                  app:contentScrim="?attr/colorPrimary"
                  app:expandedTitleMarginStart="48dp"
                  app:expandedTitleMarginEnd="64dp"
                  android:fitsSystemWindows="true"&gt;
  
  
  
                  &lt;ImageView
                      android:id="@+id/imagetoolbar"
                      android:layout_width="match_parent"
                      android:layout_height="200dp"
                      android:scaleType="centerCrop"
                      android:fitsSystemWindows="true"
                      android:foreground="@drawable/image_header_foreground"
                      app:layout_scrollFlags="scroll"
                      app:layout_collapseMode="parallax"/&gt;
  
                  &lt;android.support.v7.widget.Toolbar
                      android:id="@+id/toolbar"
                      android:layout_width="match_parent"
                      android:layout_height="?attr/actionBarSize"
                      app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
                      android:background="@drawable/theme_background"
                      app:layout_collapseMode="pin" &gt;
  
                      &lt;Spinner
                          android:id="@+id/spinner_nav"
                          android:layout_width="wrap_content"
                          android:layout_height="wrap_content"
  
                          android:dropDownVerticalOffset="?attr/actionBarSize" /&gt;
  
                  &lt;/android.support.v7.widget.Toolbar&gt;
  
              &lt;/android.support.design.widget.CollapsingToolbarLayout&gt;
  
  
          &lt;/android.support.design.widget.AppBarLayout&gt;
  
  
  
  
          &lt;android.support.v7.widget.RecyclerView
              android:id="@+id/list"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              app:layout_behavior="@string/appbar_scrolling_view_behavior" /&gt;
  
  
  
  
      &lt;/android.support.design.widget.CoordinatorLayout&gt;
  
  
      &lt;ListView
          android:layout_width="200dp"
          android:layout_height="match_parent"
          android:id="@+id/navlist"
          android:background="#dedede"
          android:layout_gravity="start" /&gt;
  
  &lt;/android.support.v4.widget.DrawerLayout&gt;
  </code></pre>
  
  <p>Now I want to include fast scrolling to my recyclerview such that the image date can be popup on scrolling.</p>
  
  <p>Sample image of such scrollbar:-
  <a href="https://i.stack.imgur.com/kMh1q.png" rel="noreferrer"><img src="https://i.stack.imgur.com/kMh1q.png" alt="Scrolling"></a></p>
  
  <p>I searched for this and tried using few libraries but I think due to my collapsing toolbar the scrollbar is not working properly. </p>
  
  <p>Screenshot of scroll Library used:-
  <a href="https://i.stack.imgur.com/2YjU1.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/2YjU1.jpg" alt="My device"></a> </p>
  
  <p>Here in my case the scroll bar is starting from top and the scroll computation is also not proper.</p>
  
  <p>Please help solving this issue.</p>
  
  <p>Thanks</p>