How to half overlap images in android constraint layout
Simplest way
<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:fitsSystemWindows="true"
>
<ImageView
android:id="@+id/appBar"
android:layout_width="match_parent"
android:layout_height="300dp"
android:background="#c2b6c2">
</ImageView>
<android.support.design.widget.FloatingActionButton
android:id="@+id/floatbtn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:src="@drawable/ic_menu_camera"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toBottomOf="@+id/appBar"
app:layout_constraintTop_toBottomOf="@+id/appBar"
/>
</android.support.constraint.ConstraintLayout>
you can set layout using only constraint layout like below :
<?xml version="1.0" encoding="utf-8"?>
<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">
<ImageView
android:id="@+id/imageView4"
android:layout_width="0dp"
android:layout_height="0dp"
android:background="@android:color/holo_orange_dark"
app:layout_constraintBottom_toTopOf="@id/guideline"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0" />
<android.support.constraint.Guideline
android:id="@+id/guideline"
android:layout_width="0dp"
android:layout_height="0dp"
android:orientation="horizontal"
app:layout_constraintGuide_percent="0.5" />
<ImageView
android:id="@+id/imageView_upper"
android:layout_width="70dp"
android:layout_height="70dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="@id/guideline"
app:layout_constraintBottom_toBottomOf="@id/guideline"
android:background="@android:color/holo_purple"/>
</android.support.constraint.ConstraintLayout>
Note: If you are using androidx then you have to use androidx.constraintlayout.widget.ConstraintLayout instead of android.support.constraint.ConstraintLayout