Passing string to included layout via data binding not working

Question

I am trying to pass a simple string to an layout from my main layout using the Android data binding feature. It compiles fine, but the value being passed to the include is not actually being passed. i.e. - it does not show up in my layout.

<?xml version="1.0" encoding="utf-8"?>
<layout 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">

    <data>
        <variable name="mytitle" type="java.lang.String"/>
    </data>

    <android.support.constraint.ConstraintLayout
        android:background="@color/black_background"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

 <include
            android:id="@+id/include1"
            layout="@layout/mylayout"
            app:mytitle="@{@string/categories}"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"/>

    </android.support.constraint.ConstraintLayout>
</layout>

My Include Layout is :

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
    <data>
        <variable name="mytitle" type="java.lang.String"/>
    </data>

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

    <TextView
        android:id="@+id/category_header_textview"
        style="@style/WhiteText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@{mytitle}"
        app:layout_constraintStart_toStartOf="parent" />

</android.support.constraint.ConstraintLayout>
</layout>

Answer 1

OK. Figured it out. Posting here for others. The thing I was missing was actually using the DataBindingUtil to set the content view.

Add the following to your onCreate():

DataBindingUtil.setContentView(this, R.layout.mylayout);