Android include layout: pass Drawable parameter using data binding gives error: AAPT: error: attribute mysrc (aka com.example.APPNAME:mysrc) not found

Question

I am trying to pass a Drawable as parameter into my include.

I have enabled dataBinding in my build.gradle file:

android {

    dataBinding {
        enabled = true
    }

    ....

}

action_bar_button.xml:

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">

    <data>
        <variable name="mysrc" type="android.graphics.drawable.Drawable"/>
    </data>

    <ImageButton android:id="@+id/notification"
        android:background="@null"
        android:foreground="?android:attr/actionBarItemBackground"
        android:layout_width="?attr/actionBarSize"
        android:layout_height="?attr/actionBarSize"
        android:padding="15dp"
        android:src="@{mysrc}"
        android:scaleType="fitCenter"></ImageButton>

</layout>

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context=".MainActivity"
    android:id="@+id/mainlayout">
    
    <include layout="@layout/action_bar_button" app:mysrc="@{@drawable/notification}"/>

</RelativeLayout>

This keeps giving me error pointing to the include statement in my activity_main.xml:

AAPT: error: attribute mysrc (aka com.example.APPNAME:mysrc) not found.

If I change the app:mysrc in activity_main.xml to android:mysrc, it gives me error:

AAPT: error: attribute android:mysrc not found.

I have been stuck with this for few hours and have tried quite a few Stack Overflow posts but can't seem to resolve it.

Answer 1

Here, there must be a drawable variable in both the action_bar_button.xml and activity_main.xml layout files

I assume you should have this in your included layout:

<data>
    <variable name="mysrc" type="android.graphics.drawable.Drawable"/>
</data>