wulkanowy-mirror/app/src/main/res/layout/fragment_lessonplan.xml

<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="io.github.wulkanowy.activity.dashboard.lessonplan.LessonplanFragment">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="Fragment Plan lekcji" />

</android.support.design.widget.CoordinatorLayout>