Signal-Android/app/src/main/res/layout/view_once_message_activity.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
    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"
    android:background="@color/core_black">

    <ImageView
        android:id="@+id/view_once_image"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="fitCenter" />

    <org.thoughtcrime.securesms.video.VideoPlayer
        android:id="@+id/view_once_video"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:visibility="gone" />

    <!-- Need this wrapper layout to get the ripple to show correctly. https://issuetracker.google.com/issues/111819099 -->
    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@color/transparent">

        <ImageView
            android:id="@+id/view_once_close_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="15dp"
            android:layout_marginTop="15dp"
            android:background="?selectableItemBackgroundBorderless"
            android:padding="4dp"
            android:src="@drawable/ic_x_24_outlined" />

    </FrameLayout>

    <TextView
        android:id="@+id/view_once_duration"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="top|end"
        android:layout_marginTop="15dp"
        android:layout_marginEnd="16dp"
        android:textAppearance="@style/ViewOnceVideo.Duration"
        android:visibility="gone"
        tools:text="00:23"
        tools:visibility="visible" />

</FrameLayout>