Quelle  activity_export_id.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/main_content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

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

    <ScrollView
        android:id="@+id/qr_container_backup"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:clipToPadding="false"
        android:fillViewport="true"
        android:paddingLeft="@dimen/tablet_additional_padding_horizontal"
        android:paddingRight="@dimen/tablet_additional_padding_horizontal">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            android:padding="@dimen/grid_unit_x2">

            <com.google.android.material.card.MaterialCardView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                app:contentPadding="@dimen/grid_unit_x1"
                app:strokeWidth="1dp">

                <TextView
                    android:id="@+id/threemaid"
                    style="@style/Threema.TextAppearance.Monospace.Large"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_margin="@dimen/grid_unit_x1"
                    android:hyphenationFrequency="none"
                    android:textIsSelectable="true"
                    tools:ignore="TouchTargetSizeCheck" />

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

            <com.google.android.material.card.MaterialCardView
                android:id="@+id/qr_container"
                android:layout_width="208dp"
                android:layout_height="208dp"
                android:layout_gravity="center_horizontal"
                android:layout_margin="@dimen/grid_unit_x2"
                app:cardElevation="-8dp"
                app:contentPadding="@dimen/grid_unit_x0_5"
                app:strokeWidth="1dp">

                <ImageView
                    android:id="@+id/qrcode_backup"
                    android:layout_width="200dp"
                    android:layout_height="200dp"
                    android:layout_gravity="center"
                    android:adjustViewBounds="false"
                    android:clickable="true"
                    android:contentDescription="@string/qr_code"
                    android:focusable="true"
                    android:foreground="?selectableItemBackground"
                    android:scaleType="fitCenter" />

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

            <TextView
                android:id="@+id/keyfingerprint"
                style="@style/Threema.TextAppearance.BodyLarge"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:paddingTop="2dp"
                android:text="@string/backup_id_summary" />

        </LinearLayout>
    </ScrollView>
</LinearLayout>