Auxio/app/src/main/res/layout/widget_large.xml

<?xml version="1.0" encoding="utf-8"?>
<android.widget.RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@android:id/background"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="?attr/colorSurface"
    android:theme="@style/Theme.Widget">

    <!--
    For this widget form to work, we need to scale the ImageView across a 1:1 aspect ratio.
    However, since we are working with a RemoteViews instance, we can't just use ConstraintLayout
    to achieve this. We can use RelativeLayout, but there's no way to force an aspect ratio with
    that layout. However, if we create an invisible ImageView that contains a massive fixed-size
    drawable and then clamp our main ImageView to it, we can make the view scale on a 1:1 aspect
    ratio.

    This is easily one of the worst layout hacks I've done, but it seems to work.
    -->

    <android.widget.ImageView
        android:id="@+id/widget_aspect_ratio"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/widget_panel"
        android:layout_alignParentStart="true"
        android:layout_alignParentTop="true"
        android:layout_alignParentEnd="true"
        android:layout_marginStart="@dimen/spacing_medium"
        android:layout_marginTop="@dimen/spacing_medium"
        android:layout_marginEnd="@dimen/spacing_medium"
        android:adjustViewBounds="true"
        android:scaleType="fitCenter"
        android:src="@drawable/ui_widget_aspect_ratio"
        android:visibility="invisible"
        tools:ignore="ContentDescription" />

    <android.widget.ImageView
        android:id="@+id/widget_cover"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_alignStart="@id/widget_aspect_ratio"
        android:layout_alignTop="@id/widget_aspect_ratio"
        android:layout_alignEnd="@id/widget_aspect_ratio"
        android:layout_alignBottom="@id/widget_aspect_ratio"
        android:src="@drawable/ic_widget_album"
        tools:ignore="ContentDescription" />

    <android.widget.LinearLayout
        android:id="@+id/widget_panel"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:padding="@dimen/spacing_medium"
        android:orientation="vertical"
        android:layout_gravity="center">

        <android.widget.TextView
            android:id="@+id/widget_song"
            style="@style/Widget.Auxio.TextView.Primary.AppWidget"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/def_widget_song" />

        <android.widget.TextView
            android:id="@+id/widget_artist"
            style="@style/Widget.Auxio.TextView.Secondary.AppWidget"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/def_widget_artist" />

        <android.widget.LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="@dimen/spacing_small">

            <android.widget.ImageButton
                android:id="@+id/widget_loop"
                style="@style/Widget.Auxio.Button.AppWidget"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:contentDescription="@string/desc_change_loop"
                android:src="@drawable/ic_loop" />

            <android.widget.ImageButton
                android:id="@+id/widget_skip_prev"
                style="@style/Widget.Auxio.Button.AppWidget"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:contentDescription="@string/desc_skip_prev"
                android:src="@drawable/ic_skip_prev" />

            <android.widget.ImageButton
                android:id="@+id/widget_play_pause"
                style="@style/Widget.Auxio.Button.AppWidget"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:contentDescription="@string/desc_play_pause"
                android:src="@drawable/sel_playing_state" />

            <android.widget.ImageButton
                android:id="@+id/widget_skip_next"
                style="@style/Widget.Auxio.Button.AppWidget"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:contentDescription="@string/desc_skip_next"
                android:src="@drawable/ic_skip_next" />

            <android.widget.ImageButton
                android:id="@+id/widget_shuffle"
                style="@style/Widget.Auxio.Button.AppWidget"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:contentDescription="@string/desc_shuffle"
                android:src="@drawable/ic_shuffle" />

        </android.widget.LinearLayout>

    </android.widget.LinearLayout>

</android.widget.RelativeLayout>