PlayerAndroid/app/src/main/res/layout/sliding_music_panel_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<code.name.monkey.retromusic.MultiSheetView 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:id="@+id/mainContent"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:id="@+id/mainContentFrame"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <View
        android:id="@+id/dimBackground"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:clickable="true"
        android:focusable="true"
        android:visibility="gone" />

    <com.google.android.material.card.MaterialCardView
        android:id="@+id/slidingPanel"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:behavior_hideable="false"
        app:behavior_peekHeight="0dp"
        app:cardBackgroundColor="?attr/colorSurface"
        app:cardCornerRadius="0dp"
        app:cardUseCompatPadding="false"
        app:layout_behavior="code.name.monkey.retromusic.CustomBottomSheetBehavior"
        app:strokeWidth="0dp">

        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:elevation="2dp"
            app:behavior_peekHeight="@dimen/bottom_sheet_peek_1_height"
            app:layout_behavior="code.name.monkey.retromusic.CustomBottomSheetBehavior">

            <FrameLayout
                android:id="@+id/playerFragmentContainer"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_marginBottom="@dimen/bottom_sheet_peek_2_height" />

            <fragment
                android:id="@+id/miniPlayerFragment"
                android:name="code.name.monkey.retromusic.fragments.MiniPlayerFragment"
                android:layout_width="match_parent"
                android:layout_height="48dp"
                tools:layout="@layout/fragment_mini_player" />

            <androidx.coordinatorlayout.widget.CoordinatorLayout
                android:id="@+id/sheet1Coordinator"
                android:layout_width="match_parent"
                android:layout_height="match_parent">

                <androidx.constraintlayout.widget.ConstraintLayout
                    android:id="@+id/sheet2"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:background="?attr/colorSurface"
                    android:elevation="2dp"
                    android:orientation="vertical"
                    app:behavior_peekHeight="@dimen/bottom_sheet_peek_2_height"
                    app:layout_behavior="code.name.monkey.retromusic.CustomBottomSheetBehavior">

                    <FrameLayout
                        android:id="@+id/sheet2PeekView"
                        android:layout_width="match_parent"
                        android:layout_height="@dimen/bottom_sheet_peek_2_height"
                        android:elevation="8dp"
                        app:layout_constraintEnd_toEndOf="parent"
                        app:layout_constraintStart_toStartOf="parent"
                        app:layout_constraintTop_toTopOf="parent">

                        <code.name.monkey.retromusic.views.StatusBarView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" />

                        <androidx.appcompat.widget.AppCompatImageView
                            android:id="@+id/thumb"
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:layout_gravity="center"
                            app:srcCompat="@drawable/ic_keyboard_arrow_up_24dp"
                            app:tint="?attr/colorControlNormal" />
                    </FrameLayout>

                    <androidx.recyclerview.widget.RecyclerView
                        android:id="@+id/sheet2Container"
                        android:layout_width="0dp"
                        android:layout_height="0dp"
                        app:layout_constraintBottom_toBottomOf="parent"
                        app:layout_constraintEnd_toEndOf="parent"
                        app:layout_constraintStart_toStartOf="parent"
                        app:layout_constraintTop_toBottomOf="@id/extendedToolbar" />

                    <FrameLayout
                        android:id="@+id/extendedToolbar"
                        android:layout_width="match_parent"
                        android:layout_height="48dp"
                        android:elevation="8dp"
                        app:layout_constraintEnd_toEndOf="parent"
                        app:layout_constraintStart_toStartOf="parent"
                        app:layout_constraintTop_toBottomOf="@id/sheet2PeekView">

                        <androidx.appcompat.widget.AppCompatImageView
                            android:id="@+id/collapseBack"
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:padding="14dp"
                            app:srcCompat="@drawable/ic_keyboard_backspace_black_24dp"
                            app:tint="?attr/colorControlNormal" />
                    </FrameLayout>
                </androidx.constraintlayout.widget.ConstraintLayout>
            </androidx.coordinatorlayout.widget.CoordinatorLayout>
        </FrameLayout>
    </com.google.android.material.card.MaterialCardView>

    <code.name.monkey.retromusic.views.BottomNavigationBarTinted
        android:id="@+id/bottomNavigationView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:elevation="0dp"
        android:visibility="gone"
        app:itemHorizontalTranslationEnabled="false"
        app:itemIconTint="@drawable/bottom_navigation_item_colors"
        app:itemTextAppearanceActive="@style/BottomSheetItemTextAppearanceActive"
        app:itemTextAppearanceInactive="@style/BottomSheetItemTextAppearanceInactive"
        app:itemTextColor="@drawable/bottom_navigation_item_colors"
        app:labelVisibilityMode="labeled"
        app:menu="@menu/bottom_navigation_main"
        tools:layout_height="56dp" />
</code.name.monkey.retromusic.MultiSheetView>