testapps/EmbmsTestDownloadApp/res/layout/activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
  ~ Copyright (C) 2017 The Android Open Source Project
  ~
  ~ Licensed under the Apache License, Version 2.0 (the "License");
  ~ you may not use this file except in compliance with 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
  -->

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/progress_window"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
    <android.support.v7.widget.RecyclerView
        android:id="@+id/downloaded_images"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:scrollbars="horizontal"
        android:horizontalSpacing="10dp"
        android:gravity="center"/>
    <Button
        android:id="@+id/bind_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/bind_button" />
    <Button
        android:id="@+id/set_temp_root_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/set_temp_root_button" />
    <Button
        android:id="@+id/get_file_services_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/get_file_services_button" />
    <Spinner
        android:id="@+id/available_file_services"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <Button
        android:id="@+id/request_dl_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/request_dl_button" />

    <GridLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:columnCount="2"
        android:orientation="vertical" >
    </GridLayout>
</LinearLayout>