developing-android-features

name: developing-android-features description: >- Implements Android features following project-specific MVI architecture, custom base classes (BaseBindingFragment/Activity), LoadSir state pages, BRVAH v3.x adapters, and internal utility APIs (onClick, dp, VLog, TranslateResource, collectWhenStarted). Use when developing any Android feature, creating new screens, implementing lists with pagination, or adding TabLayout+ViewPager2 patterns.

Android Feature Development

This skill contains project-specific conventions for Android feature development. Load the appropriate reference files based on your task.

1. Import Quick Reference

Always use project-provided utilities. Never put a full package name in a code block — always add an import statement at the top of the file.

Click Handling

import com.androidtool.common.extension.onClick

button.onClick { /* handle click */ }
button.onClick(delay = 600) { /* custom debounce */ }

Dimension Conversion

import com.androidtool.common.extension.dp

val padding = 16.dp

Screen & Device Info

import com.androidtool.common.utils.ScreenUtil

ScreenUtil.getStatusBarHeight()
ScreenUtil.getScreenWidth()
ScreenUtil.getScreenHeight()

Logging

import com.androidtool.common.log.VLog

// Always use "lilili" as primary tag
VLog.d("lilili", "Retrieved user ID: $userId")

String Resources (i18n)

import com.androidtool.common.utils.TranslateResource

binding.title = TranslateResource.getStringResources("title")

Lifecycle-aware Flow Collection

import com.androidtool.common.utils.collectWhenStarted

viewModel.uiState.collectWhenStarted { state ->
    handleUiState(state)
}

State Pages (LoadSir)

import com.androidtool.common.base.page.EmptyPage
import com.androidtool.common.base.page.ErrorPage
import com.androidtool.common.base.page.LoadingPage

// Show state pages
showState<LoadingPage>()
showState<EmptyPage>()
showState<ErrorPage> {
    val hint = view.findViewById<TextView>(R.id.hint)
    hint?.onClick { viewModel.refresh() }
}
showSuccess()  // dismiss state page, show real content

Adapter (BRVAH v3.x)

import com.chad.library.adapter.base.BaseQuickAdapter
import com.chad.library.adapter.base.BaseMultiItemQuickAdapter
import com.chad.library.adapter.base.module.LoadMoreModule
import com.chad.library.adapter.base.viewholder.BaseViewHolder

Model Package

// All model/bean classes live in com.model
import com.model.SomeBean

Network Layer

import com.androidtool.common.extension.asResult
import com.androidtool.common.extension.requestToFlow
import com.androidtool.common.troll.BaseResponse
import com.androidtool.common.net.Apis

2. Architecture Overview

• Layers: ui/ → data/ (→ optional domain/)
• No DI framework — instantiate repositories directly
• No usecase layer unless explicitly requested
• No mapper unless explicitly requested
• All models in com.model package
• Network: All API responses wrapped in BaseResponse<T>; all request params use Map<String, String>
• State management: MVI — State (StateFlow), Event (sealed interface), Effect (Channel)
• Base classes: BaseBindingFragment<VB>, BaseBindingActivity<VB> with LoadSir integration
• Adapters: BRVAH v3.x (BaseQuickAdapter, BaseMultiItemQuickAdapter, LoadMoreModule)
• Refresh: SmartRefreshLayout + custom MyRefreshLayout header

3. Feature Implementation Workflow

Choose reference files based on your task:

4. Constraints & Naming

• Layout: XML with ConstraintLayout preferred; FrameLayout/LinearLayout for simple cases
• ViewBinding: Always use ViewBinding, never findViewById in new code
• Coroutines: Prefer suspend functions and Flow; use suspendCancellableCoroutine or callbackFlow instead of callbacks
• Naming: PascalCase for classes, camelCase for functions/variables, UPPER_SNAKE_CASE for constants. Use complete descriptive names.
• Interface: No I prefix unless needed for disambiguation
• Contract file: State, Event, Effect grouped in OneFeatureContract.kt
• Chinese annotations: Add on complex logic functions and classes
• Package path: If user provides a specific package path, use it; otherwise use the feature name

5. Property Delegation Pattern

For complex logic in Activities/Fragments, delegate to specialized Impl classes with lifecycle awareness:

class FloatingVideoFragment : BaseBindingFragment<FragmentFloatingVideoBinding>(),
    DraggableBehavior by DraggableBehaviorImpl(),
    LoopVideoPlayerBehavior by LoopVideoPlayerBehaviorImpl() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        bindLifecycle(lifecycle)
    }
}

// Interface defines the contract
interface LoopVideoPlayerBehavior {
    fun bindLifecycle(lifecycle: Lifecycle)
    fun setupVideoPlayer(container: ViewPager2)
    fun startLoop()
    fun pauseLoop()
    fun releasePlayerResource()
}

// Implementation observes lifecycle
class LoopVideoPlayerBehaviorImpl : LoopVideoPlayerBehavior, DefaultLifecycleObserver {
    override fun bindLifecycle(lifecycle: Lifecycle) {
        lifecycle.addObserver(this)
    }
    override fun onResume(owner: LifecycleOwner) { /* auto resume */ }
    override fun onPause(owner: LifecycleOwner) { /* auto pause */ }
    override fun onDestroy(owner: LifecycleOwner) { releasePlayerResource() }
}

6. Reference Navigation