RecyclerView in ConstraintLayout overlapping other elements

You are using android:layout_height="wrap_content" for RecyclerView but it's looks like you need to limit height. Try it with android:layout_height="0dp". In this case it is equals to app:layout_constraintTop_toBottomOf="@+id/search_text" and app:layout_constraintBottom_toBottomOf="parent"

For some reason adding proper constraints and setting height as 0dp did not work for me(Even though it should work for most of the cases)

So I added a frame layout as the parent of the recycler view and set the height and width of recycler view as match_parent added the constraints to the frame layout.

This stopped the overlapping issue

I had the exact same problem, and adding

app:layout_constrainedHeight="true"

to the RecyclerView solved it.

try following, you have to set topConstraint of recyclerview to edittext

<?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"  >

    <EditText
        android:id="@+id/search_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:hint="search by tag..."
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <ProgressBar
        android:id="@+id/gallery_progress"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/search_text" />

    <android.support.v7.widget.RecyclerView
        android:id="@+id/gallery_list"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/search_text" />

    <TextView
        android:id="@+id/gallery_error"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/search_text"
        tools:text="error" />

</android.support.constraint.ConstraintLayout>

Output :