Tuttur (which means bind [verb] in Turkish) is lighweight library that facilitates the use of DataBinding with Activity, Fragment, Dialog, BottomSheet, and especiallly ListAdapter. Currently, tuttur works with only DataBinding. So, if you use ViewBinding or Compose, this library is useless for you.
Tuttur allows you to code simpler while using DataBinding and also reduces some boilerplates for you. The main idea is simple: Make all your Activity, Fragment, Dialog, BottomSheet and ListAdapter inherit from its Base version. For instance, you have an Activity. Don't inherit from AppCompatActivity, inherit from BaseActivity instead and specify suitable ViewDataBinding class and its layout resource id. Anymore, you have "binding" property in the Activity without needing any implementation else.
- Support for ViewBinding
- Separation of ViewBinding and DataBinding into two different modules
allprojects {
repositories {
...
maven { url 'https://jitpack.io' }
}
}implementation 'com.github.tahakorkem:tuttur:0.1.1'Make sure you are using DataBinding:
android {
buildFeatures {
dataBinding true
}
}You can find a demo app here about all the features implemented in this library.
Remember that every class you need starts with Base, such as BaseActivity, BaseFragment, BaseDialogFragment etc. Let's look at some details!
Your activity must inherit from BaseActivity and you must specify your ViewDataBinding class within angle brackets and pass layout resource id in constructor. It is important to note that you must use matching ViewDataBinding class and layout resource id.
class MainActivity : BaseActivity<ActivityMainBinding>(R.layout.activity_main) {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// "binding" property is initialized here.
}
}Your fragment must inherit from BaseFragment and you must specify your ViewDataBinding class within angle brackets and pass layout resource id in constructor.
class MovieListFragment : BaseFragment<FragmentMovieListBinding>(R.layout.fragment_movie_list) {
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
// "binding" property is available here.
}
}Your dialog must inherit from BaseDialogFragment and you must specify your ViewDataBinding class within angle brackets and pass layout resource id in constructor.
class PostDetailDialog : BaseDialogFragment<DialogPostDetailBinding>(R.layout.dialog_post_detail) {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setStyle(DialogFragment.STYLE_NO_TITLE, R.style.ThemeDialog) // You can set custom dialog style here.
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
// "binding" property is available here.
}
}Your bottom sheet must inherit from BaseBottomSheetDialogFragment and you must specify your ViewDataBinding class within angle brackets and pass layout resource id in constructor.
class MovieBottomSheet : BaseBottomSheetDialogFragment<BottomSheetMovieBinding>(R.layout.bottom_sheet_movie) {
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
// "binding" property is available here.
// you can also access "behaviour" property which is BottomSheetBehavior of your BottomSheet
behaviour.state = BottomSheetBehavior.STATE_EXPANDED
}
}Primarily, your model classes you use in ListAdapter must inherit from Identifiable that has id: Any property, equals() and hashCode() member functions. This is required to identificate each item in the list and detect value changes. Remember that using Kotlin data classes let you automatically implement equals() and hashCode() functions.
data class Movie(
override val id: Int,
val title: String,
val description: String,
val rating: Float,
) : IdentifiableSecondly, if you will have only one view type in your ListAdapter, you can use BaseListAdapter. If you have multiple view types in your ListAdapter, you can choose one of them to suit your use case: Base2ViewListAdapter, Base3ViewListAdapter, Base4ViewListAdapter, Base5ViewListAdapter, or BaseMultiViewListAdapter.
Your adapter must inherit from BaseListAdapter and you must specify both your model class and ViewDataBinding class and pass layout resource id in constructor. You can override onBind and onCreate in your adapter instead of overriding onBindViewHolder and onCreateViewHolder respectively.
class MovieAdapter(
private val callback: MovieCallback // You can pass any data to your adapter if needed
) : BaseListAdapter<Movie, ListItemMovieBinding>(R.layout.list_item_movie) {
override fun ListItemMovieBinding.onBind(
holder: BaseViewHolder<ListItemMovieBinding>,
index: Int,
item: Movie
) {
movie = item
callback = this@MovieAdapter.callback
// executePendingBindings() will be called after this function automatically
}
}Its implementation is same as above except you must override onFilter() function in your adapter. You can call filter() function from outside when you want to filter your list.
class CountryAdapter : BaseFilterableListAdapter<Country, ListItemCountryBinding>(R.layout.list_item_country) {
override fun ListItemCountryBinding.onBind(
holder: BaseViewHolder<ListItemCountryBinding>,
index: Int,
item: Country
) {
country = item
}
override fun List<Country>.onFilter(constraint: String?): List<Country> {
return filter { it.name.contains(constraint ?: "", ignoreCase = true) }
}
}In cases where you have multiple view types in your ListAdapter, it is important and useful to have type safety in both item models and ViewDataBinding classes. To provide that functionality, you can use multi view BaseListAdapters.
You must inherit from Base2ViewListAdapter, Base3ViewListAdapter, Base4ViewListAdapter, or Base5ViewListAdapter if you have at most five view types. To use more than five view types, you must inherit from BaseMultiViewListAdapter. Their implementation is similar to single view type ListAdapter except you must specify more than one model classes and ViewDataBinding classes. Additionally, you can override multiple onBindN and onCreateN functions in your adapter up to five view types. In the use of BaseMultiViewListAdapter, you can override only an onBind and onCreate function and you must struggle with different view types yourself.
It is useful to note that your all model classes must inherit from same parent in order to provide type safety.
sealed interface PostItem : Identifiable {
override val id: Int
}
interface Post : PostItem {
val author: User
val content: String?
data class Text(
override val id: Int,
override val author: User,
override val content: String
) : Post
data class Image(
override val id: Int,
override val author: User,
override val content: String?,
val imageUrl: String
) : Post
}
data class SectionHeader(
override val id: Int,
val title: String
) : PostItem
object Footer : PostItem {
override val id: Int = Int.MAX_VALUE
override fun equals(other: Any?) = other is Footer
override fun hashCode() = 0
}For instance, you have four view types in your ListAdapter for Post.Text, Post.Image, SectionHeader, and Footer and theirs ViewDataBinding classes. You must use Base4ViewListAdapter since you have four view types. Generic type parameters must be in that order: Parent model class (PostItem in this particular case), 1st model class, 1st ViewDataBinding class, 2nd model class, 2nd ViewDataBinding class, etc. You must also pass layout resource ids in constructor in form of Bindable for example as Bindable(Post.Image::class, R.layout.list_item_text_post) or bind(R.layout.list_item_text_post) in the shorthand form.
class PostAdapter
: Base4ViewListAdapter<PostItem, Post.Text, ListItemTextPostBinding, Post.Image, ListItemImagePostBinding, SectionHeader, ListItemSectionHeaderBinding, Footer, ListItemFooterBinding>(
bind(R.layout.list_item_text_post),
bind(R.layout.list_item_image_post),
bind(R.layout.list_item_section_header),
bind(R.layout.list_item_footer)
) {
override fun ListItemTextPostBinding.onBind1(
holder: BaseViewHolder<ListItemTextPostBinding>,
index: Int,
item: Post.Text
) {
textPost = item
}
override fun ListItemImagePostBinding.onBind2(
holder: BaseViewHolder<ListItemImagePostBinding>,
index: Int,
item: Post.Image
) {
imagePost = item
textViewContent.isVisible = item.content != null
}
override fun ListItemSectionHeaderBinding.onBind3(
holder: BaseViewHolder<ListItemSectionHeaderBinding>,
index: Int,
item: SectionHeader
) {
sectionHeader = item
}
}To conclude, tuttur can be useful library if you use its major features. Especially, this library make you feel more comfortable whilst you are dealing with multi-view type ListAdapters.
You can contribute to this library by fixing any issues you encountered or adding more functionalities. Fell free to open pull requests.