Quelle  activity_send_media.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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/activity_parent"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <include layout="@layout/toolbar_view" />

    <FrameLayout
        android:id="@+id/content_container"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1">

        <androidx.viewpager2.widget.ViewPager2
            android:id="@+id/view_pager"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />

        <LinearLayout
            android:id="@+id/foreground_container"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:gravity="bottom"
            android:orientation="vertical"
            android:visibility="invisible"
            tools:visibility="visible">

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

                <com.google.android.material.card.MaterialCardView
                    android:id="@+id/item_count_container"
                    style="@style/Threema.CardView.MediaViewerCaption"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="start"
                    android:layout_margin="@dimen/grid_unit_x1"
                    app:contentPaddingBottom="@dimen/grid_unit_x0_5"
                    app:contentPaddingLeft="@dimen/grid_unit_x1"
                    app:contentPaddingRight="@dimen/grid_unit_x1"
                    app:contentPaddingTop="@dimen/grid_unit_x0_5">

                    <TextView
                        android:id="@+id/item_count"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_gravity="center_horizontal"
                        android:ellipsize="end"
                        android:maxLines="1"
                        android:textColor="@android:color/white"
                        android:textSize="12sp"
                        tools:text="1 ausgewählt" />

                </com.google.android.material.card.MaterialCardView>

                <com.google.android.material.card.MaterialCardView
                    android:id="@+id/recipient_container"
                    style="@style/Threema.CardView.MediaViewerCaption"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="end"
                    android:layout_margin="@dimen/grid_unit_x1"
                    app:contentPaddingBottom="@dimen/grid_unit_x0_5"
                    app:contentPaddingLeft="@dimen/grid_unit_x1"
                    app:contentPaddingRight="@dimen/grid_unit_x1"
                    app:contentPaddingTop="@dimen/grid_unit_x0_5">

                    <ch.threema.app.emojis.EmojiTextView
                        android:id="@+id/recipient_text"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_gravity="center_horizontal"
                        android:ellipsize="end"
                        android:maxLines="1"
                        android:textColor="@android:color/white"
                        android:textSize="12sp"
                        tools:text="Senden an Gruppe" />

                </com.google.android.material.card.MaterialCardView>

            </FrameLayout>

            <FrameLayout
                android:id="@+id/dim_background"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#77000000">

                <!-- Ignoring uselessParent because we need this wrapper view to apply insets padding -->
                <LinearLayout
                    android:id="@+id/bottom_controls_container"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="vertical"
                    tools:ignore="UselessParent">

                    <FrameLayout
                        android:id="@+id/caption_input_container"
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_marginHorizontal="@dimen/grid_unit_x1"
                        android:layout_marginTop="@dimen/grid_unit_x1">

                        <ch.threema.app.ui.ComposeEditText
                            android:id="@+id/caption_edittext"
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:layout_gravity="bottom"
                            android:layout_marginRight="56dp"
                            android:background="@drawable/bubble_compose_dark_outline"
                            android:ellipsize="end"
                            android:hint="@string/add_caption_hint"
                            android:maxLength="6000"
                            android:maxLines="@integer/message_edittext_max_lines"
                            android:minHeight="@dimen/input_text_height"
                            android:nextFocusLeft="@+id/emoji_button"
                            android:nextFocusRight="@+id/attach_button"
                            android:paddingLeft="@dimen/emoji_button_width"
                            android:paddingTop="3dp"
                            android:paddingRight="45dp"
                            android:paddingBottom="4dp"
                            android:scrollHorizontally="false"
                            android:textSize="16sp">

                            <requestFocus />
                        </ch.threema.app.ui.ComposeEditText>

                        <ch.threema.app.emojis.EmojiButton
                            android:id="@+id/emoji_button"
                            style="?android:attr/borderlessButtonStyle"
                            android:layout_width="@dimen/emoji_button_width"
                            android:layout_height="@dimen/emoji_button_width"
                            android:layout_gravity="left|bottom"
                            android:layout_marginBottom="5dp"
                            android:background="@drawable/selector_compose_button"
                            android:contentDescription="@string/select_emoji"
                            android:drawablePadding="0dip"
                            android:focusable="true"
                            android:nextFocusRight="@+id/caption_edittext"
                            android:padding="@dimen/grid_unit_x1" />

                        <androidx.appcompat.widget.AppCompatImageButton
                            android:id="@+id/camera_button"
                            style="?android:attr/borderlessButtonStyle"
                            android:layout_width="@dimen/emoji_button_width"
                            android:layout_height="@dimen/emoji_button_width"
                            android:layout_gravity="bottom|right"
                            android:layout_marginRight="59dp"
                            android:layout_marginBottom="@dimen/grid_unit_x0_5"
                            android:background="@drawable/selector_compose_button"
                            android:contentDescription="@string/take_photo"
                            android:drawablePadding="0dip"
                            android:focusable="true"
                            android:nextFocusRight="@+id/send_button"
                            android:padding="@dimen/grid_unit_x1"
                            app:srcCompat="@drawable/ic_camera_outline"
                            app:tint="@android:color/white" />

                        <ch.threema.app.ui.SendButton
                            android:id="@+id/send_button"
                            android:layout_width="@dimen/input_text_height"
                            android:layout_height="@dimen/input_text_height"
                            android:layout_gravity="bottom|right"
                            android:clickable="true"
                            android:focusable="true"
                            android:foreground="@drawable/selector_avatar"
                            app:buttonTheme="1" />

                    </FrameLayout>

                    <androidx.recyclerview.widget.RecyclerView
                        android:id="@+id/item_list"
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:clipChildren="false"
                        android:clipToPadding="false"
                        android:gravity="center"
                        android:paddingHorizontal="@dimen/grid_unit_x1"
                        android:paddingVertical="@dimen/grid_unit_x1"
                        android:scrollbars="none"
                        tools:itemCount="1"
                        tools:listitem="@layout/item_send_media_add" />

                    <ViewStub
                        android:id="@+id/emoji_stub"
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:inflatedId="@+id/emoji_picker"
                        android:layout="@layout/emoji_picker_layout" />

                </LinearLayout>

            </FrameLayout>

        </LinearLayout>

    </FrameLayout>

</LinearLayout>