Awesome

Yasha

A DSL library for rendering RecyclerView and ViewPager and Compose List.

Read this in other languages: 中文, English, Changelog

Feature introduction：

✅ Support RecyclerView
✅ Support ViewPager
✅ Support MultiType
✅ Support Header and Footer
✅ Support automatic paging loading
✅ Support DiffUtil
✅ Support loading status display
✅ Support automatic clean up resources ✅ Support Compose

Prepare

1. Add jitpack to build.gradle

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

2. Add Dependencies

dependencies {
	implementation 'com.github.ssseasonnn:Yasha:1.2.0'
	
	// or
	implementation 'com.github.ssseasonnn.Yasha:yasha:1.2.0'  //only for recyclerview
	implementation 'com.github.ssseasonnn.Yasha:yasha-compose:1.2.0' //only for compose
}

Basic usage

1. Render RecyclerView

//Create data class
class RecyclerViewItem(val i: Int, val text: String = "") : YashaItem

//Create DataSource
val dataSource = YashaDataSource()

//Render RecyclerView
recyclerView.linear(dataSource) {
    renderBindingItem<RecyclerViewItem, ViewHolderNormalBinding> {
        onBind {
            itemBinding.tvNormalContent.text = "position: $position, data: $data"
        }
    }
}

2. Render ViewPager

//Create data class
class ViewPagerItem(val i: Int, val text: String = "") : YashaItem

//Create DataSource
val dataSource = YashaDataSource()

//Render ViewPager
viewPager.vertical(dataSource) {
    renderBindingItem<ViewPagerItem, ViewHolderNormalBinding> {
        onBind {
            itemBinding.tvNormalContent.text = "position: $position, data: $data"
        }
    }
}

Other configurations

1. Render Type

Yasha supports multiple types of RecyclerView, such as list, Grid, Stagger, Pager and custom list types

//Render List
recyclerView.linear(dataSource) {
    //Set the direction to vertical list or horizontal list
    orientation(RecyclerView.VERTICAL)
    renderBindingItem<NormalItem, ViewHolderNormalBinding> {}
}

//Render Grid
recyclerView.grid(dataSource) {
    //Set the number of columns
    spanCount(2)
    renderBindingItem<NormalItem, ViewHolderNormalBinding> {
        //Set the number of columns corresponding to this item
        gridSpanSize(2)
        onBind {}
    }
}

//Render waterfall flow
recyclerView.stagger(dataSource) {
    //Set the number of columns
    spanCount(2)
    renderBindingItem<NormalItem, ViewHolderNormalBinding> {
        staggerFullSpan(true)
        onBind {}
    }
}

//Render Page
recyclerView.pager(dataSource) {
    //Register page change callback
    onPageChanged { position, yashaItem, view ->
        Toast.makeText(this, "This is page $position", Toast.LENGTH_SHORT).show()
    }
}

//Render custom layout
recyclerView.custom(customLayoutManager, dataSource) {}

2. DataSource paging load

class CustomDataSource(coroutineScope: CoroutineScope) : YashaDataSource(coroutineScope) {
    var page = 0

    // Called when initializing the load
    override suspend fun loadInitial(): List<YashaItem>? {
        page = 0

        val items = mutableListOf<YashaItem>()
        for (i in 0 until 10) {
            items.add(NormalItem(i))
        }

        // Return null to trigger loading failure
        // Return to the empty list to trigger no more
        // Return init data
        return items
    }

    // Called on paging load
    override suspend fun loadAfter(): List<YashaItem>? {
        page++

        if (page % 5 == 0) {
            // Return null to trigger loading failure
            return null
        }

        val items = mutableListOf<YashaItem>()
        for (i in 0 until 10) {
            items.add(NormalItem(i))
        }

        // Return to the empty list to trigger no more
        return items
    }
}

3. Render MultiType

//Define data type A
class AItem(val i: Int) : YashaItem

//Define data type B
class BItem(val i: Int) : YashaItem

//Render Items
recyclerView.linear(dataSource) {
    //Render Type A
    renderBindingItem<AItem, AItemBinding> {
        onBind {
            //render
            ...
        }
    }
    //Render Type B
    renderBindingItem<BItem, BItemBinding> {
        onBind {
            //render
            ...
        }
    }
}

4. Header and Footer

DataSource supports the following methods for adding headers and footers:

//Headers
fun addHeader(t: T, position: Int = -1, delay: Boolean = false)
fun addHeaders(list: List<T>, position: Int = -1, delay: Boolean = false)
fun removeHeader(t: T, delay: Boolean = false)
fun setHeader(old: T, new: T, delay: Boolean = false)
fun getHeader(position: Int): T
fun clearHeader(delay: Boolean = false)

//Footers
fun addFooter(t: T, position: Int = -1, delay: Boolean = false)
fun addFooters(list: List<T>, position: Int = -1, delay: Boolean = false)
fun removeFooter(t: T, delay: Boolean = false)
fun setFooter(old: T, new: T, delay: Boolean = false)
fun getFooter(position: Int): T
fun clearFooter(delay: Boolean = false)

5. Partial refresh

By rewriting the Diff method of the data class, you can complete efficient local refresh:

//Override Diff method when defining data type
class NormalItem(val i: Int, val text: String = "") : YashaItem {

    override fun areItemsTheSame(other: Differ): Boolean {
        if (other !is NormalItem) return false
        return other.i == i
    }

    override fun areContentsTheSame(other: Differ): Boolean {
        if (other !is NormalItem) return false
        return other.text == text
    }

    //Set up payload
    override fun getChangePayload(other: Differ): Any? {
        if (other !is NormalItem) return null
        return other.text
    }
}

//Use dataSource to update the new Item data
val oldItem = NormalItem(1, "1")
val newItem = NormalItem(2, "2")
dataSource.setItem(oldItem, newItem)

// Register onBindPayload at render time
recyclerView.linear(dataSource) {
    renderBindingItem<NormalItem, ViewHolderNormalBinding> {
        onBind {
            itemBinding.tvNormalContent.text = "position: $position, data: $data"
        }

        //Partial refresh use
        onBindPayload {
            //Take out payload for partial refresh
            val payload = it[0]
            if (payload != null) {
                itemBinding.tvNormalContent.text = payload.toString()
            }
        }
    }
}

6. Custom Load Status

//Use default load state
val dataSource = YashaDataSource(enableDefaultState = true)

//Custom LoadStateItem
class CustomStateItem(val state: Int) : YashaItem
class CustomDataSource : YashaDataSource(enableDefaultState = false) {

    override fun onStateChanged(newState: Int) {
        setState(CustomStateItem(newState))
    }
}

//Render Custom State
recyclerView.linear(dataSource) {
    ...
    renderBindingItem<CustomStateItem, CustomStateItemBinding> {
        onBind {
            when (data.state) {
                FetchingState.FETCHING -> {
                    //loading...
                }
                FetchingState.FETCHING_ERROR -> {
                    //loading failed
                }
                FetchingState.DONE_FETCHING -> {
                    //loading complete
                }
                else -> {
                    //other
                }
            }
        }
    }
}

7. Proguard

Only when using reflection to create ViewBinding, you need to add the following guard rules:

-keepclassmembers class * implements androidx.viewbinding.ViewBinding {
    public static ** inflate(...);
}

License

Copyright 2021 Season.Zlc

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.