Quelle  activity_linked_devices.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout 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/parent_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="?android:attr/colorBackground"
    tools:context=".multidevice.LinkedDevicesActivity">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <com.google.android.material.appbar.MaterialToolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                tools:navigationIcon="?attr/homeAsUpIndicator"
                tools:title="Threema 2.0 for Desktop (Beta)" />

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

        </FrameLayout>

    </com.google.android.material.appbar.AppBarLayout>

    <FrameLayout
        android:id="@+id/device_list_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
            android:id="@+id/devices_list_refresh"
            android:layout_width="match_parent"
            android:layout_height="match_parent">

            <ch.threema.app.ui.EmptyRecyclerView
                android:id="@+id/devices_list"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:clipToPadding="false"
                android:paddingTop="@dimen/grid_unit_x1_5"
                android:paddingBottom="@dimen/grid_unit_x10"
                tools:itemCount="3"
                tools:listitem="@layout/item_linked_devices_list" />

        </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>

        <androidx.core.widget.NestedScrollView
            android:id="@+id/empty_text_container"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:clipToPadding="false"
            android:paddingTop="@dimen/grid_unit_x10"
            android:paddingBottom="@dimen/grid_unit_x10"
            android:visibility="gone"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">

            <TextView
                android:id="@+id/empty_text"
                style="@style/Threema.TextAppearance.BodyLarge"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginHorizontal="@dimen/grid_unit_x3"
                android:alpha="0.8"
                android:clickable="true"
                android:drawablePadding="24dp"
                android:focusable="true"
                android:gravity="center_horizontal"
                android:text="@string/md_linked_devices_empty"
                android:textColor="?attr/colorOnBackground"
                app:drawableTint="?attr/colorOnBackground"
                app:drawableTopCompat="@drawable/ic_multi_device_rounded_128dp" />

        </androidx.core.widget.NestedScrollView>

    </FrameLayout>

    <com.google.android.material.floatingactionbutton.ExtendedFloatingActionButton
        android:id="@+id/link_device_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|right"
        android:layout_margin="@dimen/grid_unit_x2"
        android:contentDescription="@string/md_link_device"
        android:text="@string/md_link_device"
        android:tint="@android:color/white"
        android:visibility="visible"
        app:icon="@drawable/ic_qr_code_scanner_rounded" />

</androidx.coordinatorlayout.widget.CoordinatorLayout>