How to set RecyclerView Max Height

ConstraintLayout offers maximum height for its children.

<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ListView
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:scrollbars="vertical"
        app:layout_constrainedHeight="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHeight_max="300dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

Here is something, you need. Subclass the RecyclerView and override onMeasure as following:

@Override
protected void onMeasure(int widthSpec, int heightSpec) {
    heightSpec = MeasureSpec.makeMeasureSpec(Utils.dpsToPixels(240), MeasureSpec.AT_MOST);
    super.onMeasure(widthSpec, heightSpec);
}

Make sure, you give proper number of pixels as the first argument in makeMeasureSpec(). I personally needed RecyclerView, that is 240dps at most.

I think this will work at least it worked for me

<androidx.constraintlayout.widget.ConstraintLayout
                android:id="@+id/Id_const_layout"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
               >
        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/Id_my_recycler"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="@dimen/margin_top_space"
            android:scrollbars="vertical"
            app:layout_constrainedHeight="true"
            app:layout_constraintBottom_toBottomOf="@+id/Id_const_layout"
            app:layout_constraintEnd_toEndOf="@+id/Id_const_layout"
            app:layout_constraintHeight_max="150dp"
            app:layout_constraintHeight_min="30dp"
            app:layout_constraintStart_toStartOf="@+id/Id_const_layout"
            app:layout_constraintTop_toTopOf="@+id/Id_const_layout"
            >
        </androidx.recyclerview.widget.RecyclerView>
            </androidx.constraintlayout.widget.ConstraintLayout>

You can change the constraintHeight_max and constraintHeight_min according to your needs.

We can optimize @Fattum 's method a little bit. We can use app:maxHeight to set the maxHeight. One can use dp or px as you like.

public class MaxHeightRecyclerView extends RecyclerView {
    private int mMaxHeight;

    public MaxHeightRecyclerView(Context context) {
        super(context);
    }

    public MaxHeightRecyclerView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initialize(context, attrs);
    }

    public MaxHeightRecyclerView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        initialize(context, attrs);
    }

    private void initialize(Context context, AttributeSet attrs) {
        TypedArray arr = context.obtainStyledAttributes(attrs, R.styleable.MaxHeightScrollView);
        mMaxHeight = arr.getLayoutDimension(R.styleable.MaxHeightScrollView_maxHeight, mMaxHeight);
        arr.recycle();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        if (mMaxHeight > 0) {
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(mMaxHeight, MeasureSpec.AT_MOST);
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
}

values/attrs.xml

<declare-styleable name="MaxHeightScrollView">
    <attr name="maxHeight" format="dimension" />
</declare-styleable>