Relative Guidelines with ConstraintLayouts. Helper code utilised in the article https://medium.com/@kuassivi/relative-guidelines-w-constraintlayouts-9533b3c546f3

relative_constraint_guideline.xml

<android.support.constraint.ConstraintLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:animateLayoutChanges="true">
    
    <!-- This View acts like a helper guideline 
         and anchors to the "relative_view" TextView. -->
    <View
        android:id="@+id/relative_guideline_1"
        app:layout_constraintBottom_toBottomOf="@+id/relative_view"
        app:layout_constraintVertical_bias="0.45" <-- Optional
        android:layout_width="0dp"
        android:layout_height="1dp"
        android:layout_marginBottom="1dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:background="@android:color/white"
        android:visibility="invisible"
        tools:visibility="visible" />
    
    <!-- This ImageView constraints its top to the guideline 
         instead of the parent. It is not vertically constraintened, 
         so it can't use bias, but it can be positioned 
         relatively to where the "relative_guideline_1" is. -->
    <ImageView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_marginTop="10dp"
        android:adjustViewBounds="true"
        android:scaleType="fitCenter"
        android:clickable="true"
        android:focusable="true"
        android:visibility="gone"
        tools:visibility="gone"
        app:layout_constraintDimensionRatio="h,1:1"
        app:layout_constraintHeight_default="percent"
        app:layout_constraintWidth_default="percent"
        app:layout_constraintHeight_percent=".4"
        app:layout_constraintWidth_percent=".4"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/relative_guideline_1"
        app:srcCompat="@drawable/vector_image" />
        
    <TextView
        android:id="@+id/relative_view"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:background="@color/red"
        android:padding="20dp"
        android:visibility="gone"
        tools:visibility="visible"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:text="@string/advise_power_save_is_on" />
        
</android.support.constraint.ConstraintLayout>