MultiTypeKTX

MultiType library makes it easier and more flexible to create multiple types for Android RecyclerView, then this library can help you make it easier to use MultiType library in Kotlin.

If you want to use ViewBinding more easily in the MultiType, you can use my other ViewBindingKTX library.

Getting started

Add it in your root build.gradle at the end of repositories:

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

Add dependencies：

dependencies {
    implementation 'com.drakeet.multitype:multitype:4.3.0'
    implementation 'com.github.DylanCaiCoding:MultiTypeKTX:0.2.0'
}

Usage

Initialize the MultiTypeAdapter

Register a single ViewDelegate , for example:

private val adapter = MultiTypeAdapter(TextViewDelegate())

Register multiple ViewDelegate , for example:

private val adapter = MultiTypeAdapter {
  register(TimeViewDelegate())
  register(MessageViewDelegate())
}

Register one-to-many ViewDelegate , for example:

private val adapter = MultiTypeAdapter {
  register(RadioOptionViewDelegate(), MultipleOptionViewDelegate())
    .withKotlinClassLinker { _, item ->
      if (item.isSingleChoice) {
        RadioOptionViewDelegate::class
      } else {
        MultipleOptionViewDelegate::class
      }
    }
}

Jetpack MVVM + MultiType + DiffUtil

Step 1. Add a variable of the ItemsLiveData<T> type in ViewModel, for example:

class MessageListViewModel : ViewModel() {
  val items = ItemsLiveData<Any>()
}

Or if you register a single ViewDelegate, you can use specific types, for example:

val items = ItemsLiveData<Message>()

Step 2. Observe items changes. The code block returns whether the old and new items are the same, for example:

adapter.observeItemsChanged(this, viewModel.items) { oldItem, newItem ->
  (oldItem is String && newItem is String && oldItem == newItem) ||
      (oldItem is Message && newItem is Message && oldItem.id == newItem.id)
}

Step 3. After changing the list data, you can set the list data to the ItemsLiveData<T> variable, for example:

items.value = list

Check one or more

Step 1. The entity class implement ICheckable interface, for example:

data class Option(
  val id : Int,
  val name: String,
  override val groupId: Int, // Add it when you need to check it separately
  override var isChecked: Boolean = false
) : ICheckable

Step 2. Create a class extends CheckableItemViewDelegate<T : ICheckable, VH : ViewHolder>, for example:

class RadioOptionViewDelegate :
  CheckableItemViewDelegate<Option, BindingViewHolder<ItemOptionBinding>>(CheckType.SINGLE) {

  override fun onCreateViewHolder(context: Context, parent: ViewGroup) =
    BindingViewHolder<ItemOptionBinding>(parent)
      .onItemClick { position ->
        checkItem(position) // When you need to change the checked state
      }

  override fun onBindViewHolder(holder: BindingViewHolder<ItemOptionBinding>, item: Option) {
    with(holder.binding) {
      checkBox.text = item.name
      checkBox.isChecked = item.isChecked
    }
  }
}

The constructor of CheckableItemViewDelegate has a CheckType argument. There are the following options.

type	function
CheckType.SINGLE	Single choice
CheckType.MULTIPLE	Multiple choice
CheckType.limit(number)	Limit the number of checked

Change log

Releases

License

Copyright (C) 2021. Dylan Cai

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.