<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/strograycc_solno"
    android:orientation="vertical">


    <android.support.constraint.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <Button
            android:id="@+id/btn_scaleX"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_marginTop="8dp"
            android:layout_marginBottom="8dp"
            android:background="@drawable/circle_black"
            android:text="가로 조절"
            android:textColor="@android:color/white"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toStartOf="@+id/btn_scaleY"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <Button
            android:id="@+id/btn_scaleY"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_marginTop="8dp"
            android:layout_marginBottom="8dp"
            android:background="@drawable/circle_black"
            android:text="세로 조절"
            android:textColor="@android:color/white"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toStartOf="@+id/btn_scaleXY"
            app:layout_constraintStart_toEndOf="@+id/btn_scaleX"
            app:layout_constraintTop_toTopOf="parent" />

        <Button
            android:id="@+id/btn_scaleXY"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_marginTop="8dp"
            android:layout_marginBottom="8dp"
            android:background="@drawable/circle_black"
            android:text="가로/세로\n조절"
            android:textColor="@android:color/white"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toEndOf="@+id/btn_scaleY"
            app:layout_constraintTop_toTopOf="parent" />

    </android.support.constraint.ConstraintLayout>

    <android.support.constraint.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <Button
            android:id="@+id/btn_scaleX_"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_marginTop="8dp"
            android:layout_marginBottom="8dp"
            android:background="@drawable/circle_black"
            android:scaleX="0.5"
            android:text="가로 조절"
            android:textColor="@android:color/white"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toStartOf="@+id/btn_scaleY_"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <Button
            android:id="@+id/btn_scaleY_"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_marginTop="8dp"
            android:layout_marginBottom="8dp"
            android:background="@drawable/circle_black"
            android:scaleY="0.5"
            android:text="세로 조절"
            android:textColor="@android:color/white"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toStartOf="@+id/btn_scaleXY_"
            app:layout_constraintStart_toEndOf="@+id/btn_scaleX_"
            app:layout_constraintTop_toTopOf="parent" />

        <Button
            android:id="@+id/btn_scaleXY_"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_marginTop="8dp"
            android:layout_marginBottom="8dp"
            android:background="@drawable/circle_black"
            android:scaleX="0.5"
            android:scaleY="0.5"
            android:text="가로/세로\n조절"
            android:textColor="@android:color/white"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toEndOf="@+id/btn_scaleY_"
            app:layout_constraintTop_toTopOf="parent" />

    </android.support.constraint.ConstraintLayout>

</LinearLayout>