session-android/res/layout/expiration_dialog.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:orientation="vertical"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:gravity="center">

    <cn.carbswang.android.numberpickerview.library.NumberPickerView
            android:id="@+id/expiration_number_picker"
            android:layout_alignParentTop="true"
            app:npv_WrapSelectorWheel="false"
            app:npv_DividerColor="#cbc8ea"
            app:npv_TextColorNormal="?conversation_number_picker_text_color_normal"
            app:npv_TextColorSelected="?conversation_number_picker_text_color_selected"
            app:npv_ItemPaddingVertical="20dp"
            app:npv_TextColorHint="@color/grey_600"
            app:npv_TextSizeNormal="16sp"
            app:npv_TextSizeSelected="16sp"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

    <TextView android:id="@+id/expiration_details"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:layout_below="@id/expiration_number_picker"
              android:minLines="3"
              android:padding="20dp"
              tools:text="Your messages will not expire."/>


</RelativeLayout>