session-android/res/layout/scribble_hud.xml

<?xml version="1.0" encoding="utf-8"?>
<merge
    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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:parentTag="android.widget.LinearLayout"
    tools:background="@color/core_grey_60">

    <android.support.constraint.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:animateLayoutChanges="true">

        <LinearLayout
            android:id="@+id/scribble_toolbar"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentEnd="true"
            android:layout_gravity="top|end"
            android:layout_marginTop="8dp"
            android:layout_marginEnd="10dp"
            android:animateLayoutChanges="true"
            android:orientation="horizontal"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintTop_toTopOf="parent">

            <ImageView
                android:id="@+id/scribble_delete_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackgroundBorderless"
                android:padding="8dp"
                android:src="@drawable/ic_trash_outline_36" />

            <ImageView
                android:id="@+id/scribble_undo_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackgroundBorderless"
                android:padding="8dp"
                android:src="@drawable/ic_undo_36" />

            <ImageView
                android:id="@+id/scribble_draw_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackgroundBorderless"
                android:padding="8dp"
                android:src="@drawable/ic_marker_36" />

            <ImageView
                android:id="@+id/scribble_highlight_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackgroundBorderless"
                android:padding="8dp"
                android:src="@drawable/ic_highlighter_36" />

            <ImageView
                android:id="@+id/scribble_text_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackgroundBorderless"
                android:padding="8dp"
                android:src="@drawable/ic_text_36" />

            <ImageView
                android:id="@+id/scribble_sticker_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackgroundBorderless"
                android:padding="8dp"
                android:src="@drawable/ic_camera_emoji_36" />

            <ImageView
                android:id="@+id/scribble_confirm_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackgroundBorderless"
                android:padding="8dp"
                android:src="@drawable/ic_check_circle_filled_36" />

        </LinearLayout>

        <org.thoughtcrime.securesms.scribbles.widget.VerticalSlideColorPicker
            android:id="@+id/scribble_color_picker"
            android:layout_width="32dp"
            android:layout_height="250dp"
            android:layout_below="@id/scribble_toolbar"
            android:layout_gravity="center_horizontal"
            android:layout_marginTop="32dp"
            android:layout_marginEnd="10dp"
            app:layout_constraintEnd_toEndOf="@+id/scribble_toolbar"
            app:layout_constraintTop_toBottomOf="@+id/scribble_toolbar"
            app:pickerBorderColor="@color/white"
            app:pickerBorderWidth="3dp"
            app:pickerColors="@array/scribble_colors" />

        <android.support.v7.widget.RecyclerView
            android:id="@+id/scribble_color_palette"
            android:layout_width="wrap_content"
            android:layout_height="0dp"
            android:layout_below="@id/scribble_color_picker"
            android:layout_alignEnd="@id/scribble_color_picker"
            android:layout_gravity="center_horizontal"
            android:layout_marginBottom="8dp"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="@+id/scribble_color_picker"
            app:layout_constraintTop_toBottomOf="@+id/scribble_color_picker"
            app:layout_constraintVertical_bias="0.0" />

    </android.support.constraint.ConstraintLayout>

</merge>