activity_ruler_demo.xml

<?xml version="1.0" encoding="utf-8"?><!--
  ~ Copyright 2018 Keval Patel
  ~
  ~ Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance wit
  ~ the License. You may obtain a copy of the License at
  ~
  ~ http://www.apache.org/licenses/LICENSE-2.0
  ~
  ~ Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
  ~ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for
  ~  the specific language governing permissions and limitations under the License.
  -->

<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=".RulerDemoActivity">

    <com.kevalpatel2106.rulerpicker.ScrollingValuePicker
        android:id="@+id/ruler_view_demo"
        android:layout_width="match_parent"
        android:layout_height="100dp"
        android:background="@android:color/holo_green_dark"/>


    <TextView
        android:id="@+id/selected_ruler_value_tv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/ruler_view_demo"
        android:layout_marginTop="10dp"
        tools:text="100"/>
</RelativeLayout>