RecyclerView in ConstraintLayout is not showing properly

Question

I tested this xml with chaining, Guideline and Barrier but none of them could help.

The xml code:

<?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"
    tools:context=".RatingActivity">

    <TextView
        android:id="@+id/welcomeTextView"
        android:layout_width="0dp"
        android:layout_height="74dp"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="79dp"
        android:gravity="clip_vertical|center_horizontal"
        android:text="@string/welcome"
        android:textAppearance="@style/TextAppearance.AppCompat.Medium"
        android:textStyle="bold"
        app:layout_constraintBottom_toTopOf="@+id/recyclerView"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.0" />

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="0dp"
        android:layout_height="467dp"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="24dp"
        android:background="@android:color/darker_gray"
        android:padding="4dp"
        android:scrollbars="vertical"
        app:layout_constraintBottom_toTopOf="@+id/submitButton"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent" />

    <Button
        android:id="@+id/submitButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="8dp"
        android:text="@string/submit"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

</android.support.constraint.ConstraintLayout>

When it runs on an AVD, the RecyclerView takes more space than what is needed causing it to cover or push back either welcomeTextView or submitButton.

BTW, this is the Gradle dependency:

implementation 'com.android.support.constraint:constraint-layout:1.1.3'

Answer 1

Try:

<?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">

    <TextView
        android:id="@+id/welcomeTextView"
        android:layout_width="0dp"
        android:layout_height="74dp"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="79dp"
        android:gravity="clip_vertical|center_horizontal"
        android:text="welcome"
        android:textAppearance="@style/TextAppearance.AppCompat.Medium"
        android:textStyle="bold"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.0" />

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="24dp"
        android:background="@android:color/darker_gray"
        android:padding="4dp"
        android:scrollbars="vertical"
        app:layout_constrainedHeight="true"
        app:layout_constraintTop_toBottomOf="@+id/welcomeTextView"
        app:layout_constraintBottom_toTopOf="@id/submitButton" />

    <Button
        android:id="@+id/submitButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="8dp"
        android:text="submit"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

</android.support.constraint.ConstraintLayout>

The only change is set the top of your RecyclerView instead the bottom of your text, and then set the RecyclerView height to 0 and set the app:layout_constrainedHeight="true" to enable the height calculation based on constraints. If the welcome message bottom margin doesn't work, try to set a top margin to the RecyclerView.