felipeespitalher / BindingRecyclerView

BindingRecyclerView

Reduce boilerplate code with RecyclerViews by using Android's data binding and naming convention.

Example

Create an adapter extending BindingRecyclerView, similarly to RecyclerView, provide a list of elements and override a few methods:

class MyRecyclerViewAdapter : BindingRecyclerView<TitleViewModel>() {

    var viewModels = listOf<BindingRecyclerView.BindableViewHolder>()
            set(value) {
                field = value
                notifyDataSetChanged()
            }
    
    override fun getViewModelForPosition(position: Int): BindableViewHolder {
        return viewModels[position]
    }
    
    override fun getItemCount(): Int {
        return viewModels.size
    }
    
}

You must have a ViewModel that extends BindingRecyclerView.BindableViewHolder:

data class TitleViewModel(
        val title: String,
        val clickCallback: (() -> Unit)? = null
) : BindingRecyclerView.BindableViewHolder {

    override val layoutId: Int = R.layout.title_view_item

}

And your layout:

<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools">

    <data>

        <variable
            name="viewModel"
            type="package.name.TitleViewModel" />

    </data>

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@{viewModel.title}" />

    </FrameLayout>

</layout>

Configuration

All item layouts of the recycler view must have a variable named viewModel. In your application class you must inform the BR id of the variable into BindingRecyclerViewConfig.

Simply as this:

class App: Application() {

    override fun onCreate() {
        super.onCreate()

        BindingRecyclerViewConfig.init(object: BindingRecyclerViewConfig.ViewModelBrId() {
            override val id: Int = BR.viewModel
        })
    }
}

Aditional info

In case you need you need a recycler view different layouts, we got you covered! Simply provide multiple implementations of BindingRecyclerView.BindableViewHolder.

If you are creating an Adapter based on a List you can use the following implementations of BindingRecyclerView:

• BindingMutableListRecyclerView
• BindingListRecyclerView

Get it

Add the JitPack repository to your root build.gradle:

allprojects {
    repositories {
        ...
        maven { url 'https://jitpack.io' }
    }
}

Add the dependency

repositories {
    implementation 'com.github.gianei:BindingRecyclerView:1.1.0'
}