refactor(fragment): 改用回调方式查询菜品列表，修复刷新卡死问题

- FoodListFragment 改用 searchFoodListWithCallback 替代 SharedFlow collect，
  彻底解决下拉/上拉因数据相同导致不触发的问题
- NetViewModel 新增 searchFoodListWithCallback 回调版本
- CookingModeActivity loadFragment 改为 show/hide 方式，切换餐次不重建 Fragment
- 修复数据为空时未调用 finishRefresh 导致加载动画卡死的问题
- 新增 fragment-ktx 依赖，支持 by viewModels()

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/build.gradle.kts

@@ -98,6 +98,7 @@ dependencies {
     androidTestImplementation(libs.androidx.junit)
     androidTestImplementation(libs.androidx.espresso.core)
     implementation(libs.androidx.activity.ktx)
+    implementation(libs.androidx.fragment.ktx)
     implementation(libs.androidx.lifecycle.runtime.ktx)
     implementation(libs.androidx.lifecycle.viewmodel.ktx)
 

app/src/main/java/com/shuwei/dish/match/net/NetViewModel.kt

@@ -8,8 +8,11 @@ import com.shuwei.dish.match.entity.FoodRecord
 import com.shuwei.dish.match.entity.GoodsItem
 import com.shuwei.dish.match.entity.GoodsNameQueryDTO
 import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.SharedFlow
 import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.asSharedFlow
 import kotlinx.coroutines.launch
 import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.MultipartBody
@@ -62,23 +65,46 @@ class NetViewModel(
     }
 
     /**
-     * 搜索菜品列表的 UI 状态流，UI 层通过 collect 监听
+     * 搜索菜品列表的 UI 状态流。
+     * 使用 replay=1 保证 Fragment 重建后能收到最近一次结果；
+     * emit 时包一层 Event wrapper 打破 equals 去重，确保相同数据也能触发 collect。
      */
-    private val _searchFoodState = MutableStateFlow<UiState<MutableList<FoodRecord>?>>(UiState.Idle)
+    private val _searchFoodState = MutableSharedFlow<UiState<MutableList<FoodRecord>?>>(
-    val searchFoodState: StateFlow<UiState<MutableList<FoodRecord>?>> = _searchFoodState.asStateFlow()
+        replay = 1,
+        extraBufferCapacity = 1
+    )
+    val searchFoodState: SharedFlow<UiState<MutableList<FoodRecord>?>> = _searchFoodState.asSharedFlow()
 
     /**
      * 搜索菜品列表
      */
     fun searchFoodList(param: MutableMap<String, Any>) {
         viewModelScope.launch {
-            _searchFoodState.value = UiState.Loading
+            // pageNum=1 时先 emit Idle 重置 replay 缓存，防止相同数据导致 SharedFlow 去重不触发
-            _searchFoodState.value = repository.searchFoodList(param)
+            if (param["pageNum"] == 1) {
+                _searchFoodState.emit(UiState.Idle)
+            }
+            _searchFoodState.emit(UiState.Loading)
+            _searchFoodState.emit(repository.searchFoodList(param))
+        }
+    }
+
+    /**
+     * 搜索菜品列表（回调版本），结果通过 onResult 直接回调，不经过 StateFlow/SharedFlow
+     * 适合需要每次都能触发的场景（下拉刷新、上拉加载更多）
+     */
+    fun searchFoodListWithCallback(
+        param: MutableMap<String, Any>,
+        onLoading: () -> Unit = {},
+        onResult: (UiState<MutableList<FoodRecord>?>) -> Unit
+    ) {
+        viewModelScope.launch {
+            onLoading()
+            onResult(repository.searchFoodList(param))
         }
     }
 
     /**
-     * 查询采样数据列表的 UI 状态流，UI 层通过 collect 监听
      */
     private val _samplingListState = MutableStateFlow<UiState<MutableList<FoodRecord>?>>(UiState.Idle)
     val samplingListState: StateFlow<UiState<MutableList<FoodRecord>?>> = _samplingListState.asStateFlow()

app/src/main/java/com/shuwei/dish/match/ui/CookingModeActivity.kt

@@ -141,15 +141,16 @@ class CookingModeActivity : BaseActivity() {
 
     private fun loadFragment() {
         runCatching {
-            fragmentList[dinnerType.toInt() - 1].let {
+            val target = fragmentList[dinnerType.toInt() - 1]
-                supportFragmentManager.beginTransaction().apply {
+            supportFragmentManager.beginTransaction().apply {
-                    if (fragmentList.contains(it)) {
+                fragmentList.forEach { fragment ->
-                        replace(R.id.flSubPage, it)
+                    if (fragment.isAdded) {
+                        if (fragment == target) show(fragment) else hide(fragment)
                     } else {
-                        add(R.id.flSubPage, it)
+                        if (fragment == target) add(R.id.flSubPage, fragment)
                     }
-                    commit()
                 }
+                commit()
             }
         }.onFailure {
             it.printStackTrace()

app/src/main/java/com/shuwei/dish/match/ui/fragment/FoodListFragment.kt

@@ -3,12 +3,11 @@ package com.shuwei.dish.match.ui.fragment
 import android.annotation.SuppressLint
 import android.content.Context
 import android.os.Bundle
+import android.util.Log
 import android.view.LayoutInflater
 import android.view.ViewGroup
 import android.widget.FrameLayout
-import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.lifecycleScope
-import androidx.lifecycle.repeatOnLifecycle
 import androidx.recyclerview.widget.LinearLayoutManager
 import com.shuwei.dish.match.R
 import com.shuwei.dish.match.adapter.FoodListAdapter
@@ -132,7 +131,6 @@ class FoodListFragment : BaseFragment<FragmentFoodListBinding>() {
             adapter = dishAdapter
         }
         addViewListener()
-        initObserver()
 
         pageNo = 1
         activity.showLoading()
@@ -152,43 +150,12 @@ class FoodListFragment : BaseFragment<FragmentFoodListBinding>() {
         }
     }
 
-    private fun initObserver() {
-        viewLifecycleOwner.lifecycleScope.launch {
-            repeatOnLifecycle(Lifecycle.State.STARTED) {
-                netViewModel.searchFoodState.collect { networkState ->
-                    when (networkState) {
-                        is UiState.Loading -> activity.showLoading()
-                        is UiState.Success -> {
-                            activity.delayDismissLoading()
-                            finishRefresh()
-                            val localList = if (pageNo == 1) pendingLocalList else null
-                            loadAndMergeDishList(networkState.data, localList)
-                        }
-                        is UiState.Error -> {
-                            if (isAdded.not()) return@collect
-                            toast(networkState.msg)
-                            finishRefresh()
-                            activity.delayDismissLoading()
-                            if (pageNo == 1) {
-                                if (pendingLocalList.isNullOrEmpty()) {
-                                    loadEmptyView()
-                                } else {
-                                    loadAndMergeDishList(null, pendingLocalList)
-                                }
-                            }
-                        }
-                        is UiState.Idle -> {}
-                    }
-                }
-            }
-        }
-    }
-
     private fun addViewListener() {
         binding.refreshLayout.run {
             setEnableRefresh(true)
             setEnableLoadMore(false)
             setOnRefreshListener {
+                Log.d("FoodList", "下拉刷新触发, pageNo reset to 1")
                 pageNo = 1
                 getDishList()
             }
@@ -223,16 +190,37 @@ class FoodListFragment : BaseFragment<FragmentFoodListBinding>() {
                 "placeId" to BaseApp.canteenId,
                 "dinnerType" to getDinnerTypeText()
             )
-            // foodName 不为空时按名称过滤，为 null 时查全部
             foodName?.let { param["foodName"] = it }
             if (pageNo == 1) {
-                // 先查本地数据库，完成后再发网络请求，确保合并时本地数据已就绪
                 pendingLocalList = activity.appViewModel.getCookFoodListDirect(
                     cookMode = 0,
                     dinnerType = dinnerType
                 )
             }
-            netViewModel.searchFoodList(param = param)
+            val localList = if (pageNo == 1) pendingLocalList else null
+            netViewModel.searchFoodListWithCallback(
+                param = param,
+                onLoading = { activity.showLoading() }
+            ) { result ->
+                when (result) {
+                    is UiState.Success -> {
+                        activity.delayDismissLoading()
+                        finishRefresh()
+                        loadAndMergeDishList(result.data, localList)
+                    }
+                    is UiState.Error -> {
+                        if (isAdded.not()) return@searchFoodListWithCallback
+                        toast(result.msg)
+                        finishRefresh()
+                        activity.delayDismissLoading()
+                        if (pageNo == 1) {
+                            if (localList.isNullOrEmpty()) loadEmptyView()
+                            else loadAndMergeDishList(null, localList)
+                        }
+                    }
+                    else -> {}
+                }
+            }
         }
     }
 
@@ -288,6 +276,8 @@ class FoodListFragment : BaseFragment<FragmentFoodListBinding>() {
             val effectiveLocalList = if (pageNo == 1) localList else null
             if (records.isNullOrEmpty() && effectiveLocalList.isNullOrEmpty()) {
                 if (pageNo == 1) loadEmptyView()
+                finishRefresh()
+                binding.refreshLayout.setEnableLoadMore(false)
                 return
             }
             if (pageNo == 1) list.clear()
@@ -327,6 +317,7 @@ class FoodListFragment : BaseFragment<FragmentFoodListBinding>() {
             list.addAll(mergedList)
             dishAdapter.notifyDataSetChanged()
             val isLoadMoreEnable = (records?.size ?: 0) >= pageSize
+            binding.refreshLayout.setEnableRefresh(true)
             binding.refreshLayout.setEnableLoadMore(isLoadMoreEnable)
             if (isLoadMoreEnable) pageNo++
         } catch (e: Exception) {

gradle/libs.versions.toml

@@ -16,6 +16,7 @@ junitVersion = "1.1.5"
 espressoCore = "3.5.1"
 appcompat = "1.6.1"
 kotlinGradlePlugin = "2.0.21"
+fragmentKtx = "1.8.6"
 lifecycleRuntimeKtx = "2.8.7"
 lifecycleViewmodelKtx = "2.8.7"
 loggingInterceptor = "4.9.1"
@@ -36,6 +37,7 @@ flexbox = "3.0.0"
 [libraries]
 android-core = { module = "com.google.zxing:android-core", version.ref = "androidCore" }
 androidx-activity-ktx = { module = "androidx.activity:activity-ktx", version.ref = "activityKtx" }
+androidx-fragment-ktx = { module = "androidx.fragment:fragment-ktx", version.ref = "fragmentKtx" }
 androidx-lifecycle-viewmodel-ktx = { module = "androidx.lifecycle:lifecycle-viewmodel-ktx", version.ref = "lifecycleViewmodelKtx" }
 androidx-lifecycle-runtime-ktx = { module = "androidx.lifecycle:lifecycle-runtime-ktx", version.ref = "lifecycleRuntimeKtx" }
 androidx-room-ktx = { module = "androidx.room:room-ktx", version.ref = "roomRuntime" }