View binding with EpoxyModelWithHolder

Question

I am using EpoxyModelWithHolder with multiple layouts in a single Epoxy model class. How can I do ViewBinding? Currently, I am using Kotlin-android-extensions . Below is my code

@EpoxyModelClass
abstract class ItemSampleEpoxyModel : EpoxyModelWithHolder() {

@EpoxyAttribute
var itemSampleShelf: ComponentFactoryLanderPagesHeroShelf.ComponentLanderPageHeroShelf.ItemLanderPageHeroShelf? =
    null

override fun getDefaultLayout() =
    when {
        itemSampleShelf?.heroStyle == "Project" -> {
            R.layout.item_project_sample
        }
        itemSampleShelf?.shelfItemType == "Course" -> {
            R.layout.item_course_sample
        }
        else -> {
            R.layout.item_sample
        }
    }

override fun bind(itemHolder: ItemSampleEpoxyHolder) {
    itemHolder.titleView.text = itemSampleShelf?.title
} }



class ItemSampleEpoxyHolder : EpoxyHolder() {


lateinit var titleView: AppCompatTextView

override fun bindView(itemView: View) {
    titleView = itemView.tv_title
}}

Answer 1

First add dependency of epoxy:

def epoxyVersion = '4.6.3'
implementation "com.airbnb.android:epoxy:$epoxyVersion"
implementation "com.airbnb.android:epoxy-databinding:$epoxyVersion"
kapt "com.airbnb.android:epoxy-processor:$epoxyVersion"

After that we need to configure epoxy. In order to do this we need to make a package-info.java file inside the app module and write the below code.

@EpoxyDataBindingPattern(rClass = R.class, layoutPrefix = "epoxy_item")
interface Config {
}

Then we need to keep one thing in mind that whenever we are creating a layout it should be a data binding layout and its name should follow the value defined in the layoutPrefix variable in package-info for example in my case the layoutPrefix is epoxy_item so whenever I name a layout it starts with epoxy_item .

Sample Layout: (Layout Name -> epoxy_item_loading)

<?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">

<data>

    <variable
        name="isVisible"
        type="Boolean" />


</data>

<androidx.constraintlayout.widget.ConstraintLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:isVisible="@{isVisible}">

    <ProgressBar
        android:layout_width="20dp"
        android:layout_height="20dp"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="10dp"
        android:theme="@style/ProgressBlueTheme"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
 </layout>

Now to add this layout to epoxy recycler view:

        epoxyRecycler.withModels {
               loading {
                id("progress layout")
                isVisible(isLoading)// boolean variable
            }
        }

That's all we need to do:)