<?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"
android:layout_width="49dp"
android:layout_height="88dp">
<TextView
android:id="@id/tv_day_of_month"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:gravity="center"
android:lineSpacingExtra="12sp"
android:textColor="@color/colorBlack"
android:textSize="12sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.v7.widget.RecyclerView>
</android.support.constraint.ConstraintLayout>
But seems to be not working. Any help will be appreciate it