Prevent possible crash when showing results for other languages

app/src/main/java/org/wikipedia/search/SearchResultsFragment.kt

@@ -176,31 +176,32 @@ class SearchResultsFragment : Fragment() {
 
     private inner class NoSearchResultAdapter : RecyclerView.Adapter<NoSearchResultItemViewHolder>() {
         override fun onBindViewHolder(holder: NoSearchResultItemViewHolder, position: Int) {
-            holder.bindItem(position, viewModel.resultsCount[position])
+            holder.bindItem(viewModel.countsPerLanguageCode[position])
         }
 
         override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): NoSearchResultItemViewHolder {
             return NoSearchResultItemViewHolder(ItemSearchNoResultsBinding.inflate(layoutInflater, parent, false))
         }
 
-        override fun getItemCount(): Int { return viewModel.resultsCount.size }
+        override fun getItemCount(): Int { return viewModel.countsPerLanguageCode.size }
     }
 
     private inner class NoSearchResultItemViewHolder(val itemBinding: ItemSearchNoResultsBinding) : DefaultViewHolder<View>(itemBinding.root) {
         private val accentColorStateList = getThemedColorStateList(requireContext(), R.attr.progressive_color)
         private val secondaryColorStateList = getThemedColorStateList(requireContext(), R.attr.secondary_color)
-        fun bindItem(position: Int, resultsCount: Int) {
-            if (resultsCount == 0 && viewModel.invokeSource == Constants.InvokeSource.PLACES) {
+        fun bindItem(resultPair: Pair<String, Int>) {
+            val langCode = resultPair.first
+            val resultCount = resultPair.second
+            if (resultCount == 0 && viewModel.invokeSource == Constants.InvokeSource.PLACES) {
                 PlacesEvent.logAction("no_results_impression", "search_view")
             }
-            val langCode = WikipediaApp.instance.languageState.appLanguageCodes[position]
-            itemBinding.resultsText.text = if (resultsCount == 0) getString(R.string.search_results_count_zero) else resources.getQuantityString(R.plurals.search_results_count, resultsCount, resultsCount)
-            itemBinding.resultsText.setTextColor(if (resultsCount == 0) secondaryColorStateList else accentColorStateList)
-            itemBinding.languageCode.visibility = if (viewModel.resultsCount.size == 1) View.GONE else View.VISIBLE
+            itemBinding.resultsText.text = if (resultCount == 0) getString(R.string.search_results_count_zero) else resources.getQuantityString(R.plurals.search_results_count, resultCount, resultCount)
+            itemBinding.resultsText.setTextColor(if (resultCount == 0) secondaryColorStateList else accentColorStateList)
+            itemBinding.languageCode.visibility = if (viewModel.countsPerLanguageCode.size == 1) View.GONE else View.VISIBLE
             itemBinding.languageCode.setLangCode(langCode)
-            itemBinding.languageCode.setTextColor(if (resultsCount == 0) secondaryColorStateList else accentColorStateList)
-            itemBinding.languageCode.setBackgroundTint(if (resultsCount == 0) secondaryColorStateList else accentColorStateList)
-            view.isEnabled = resultsCount > 0
+            itemBinding.languageCode.setTextColor(if (resultCount == 0) secondaryColorStateList else accentColorStateList)
+            itemBinding.languageCode.setBackgroundTint(if (resultCount == 0) secondaryColorStateList else accentColorStateList)
+            view.isEnabled = resultCount > 0
             view.setOnClickListener {
                 if (!isAdded) {
                     return@setOnClickListener

app/src/main/java/org/wikipedia/search/SearchResultsViewModel.kt

@@ -26,20 +26,20 @@ class SearchResultsViewModel : ViewModel() {
 
     private val batchSize = 20
     private val delayMillis = 200L
-    var resultsCount = mutableListOf<Int>()
+    var countsPerLanguageCode = mutableListOf<Pair<String, Int>>()
     var searchTerm: String? = null
     var languageCode: String? = null
     lateinit var invokeSource: Constants.InvokeSource
 
     @OptIn(FlowPreview::class) // TODO: revisit if the debounce method changed.
     val searchResultsFlow = Pager(PagingConfig(pageSize = batchSize, initialLoadSize = batchSize)) {
-        SearchResultsPagingSource(searchTerm, languageCode, resultsCount, invokeSource)
+        SearchResultsPagingSource(searchTerm, languageCode, countsPerLanguageCode, invokeSource)
     }.flow.debounce(delayMillis).cachedIn(viewModelScope)
 
     class SearchResultsPagingSource(
         private val searchTerm: String?,
         private val languageCode: String?,
-        private var resultsCount: MutableList<Int>?,
+        private var countsPerLanguageCode: MutableList<Pair<String, Int>>,
         private var invokeSource: Constants.InvokeSource
     ) : PagingSource<Int, SearchResult>() {
 
@@ -93,14 +93,12 @@ class SearchResultsViewModel : ViewModel() {
                 }
 
                 if (resultList.isEmpty() && response?.continuation == null) {
-                    resultsCount?.clear()
+                    countsPerLanguageCode.clear()
                     WikipediaApp.instance.languageState.appLanguageCodes.forEach { langCode ->
-                        if (langCode == languageCode) {
-                            resultsCount?.add(0)
-                        } else {
+                        var countResultSize = 0
+                        if (langCode != languageCode) {
                             val prefixSearchResponse = ServiceFactory.get(WikiSite.forLanguageCode(langCode))
                                     .prefixSearch(searchTerm, params.loadSize, 0)
-                            var countResultSize = 0
                             prefixSearchResponse.query?.pages?.let {
                                 countResultSize = it.size
                             }
@@ -109,12 +107,8 @@ class SearchResultsViewModel : ViewModel() {
                                         .fullTextSearch(searchTerm, params.loadSize, null)
                                 countResultSize = fullTextSearchResponse.query?.pages?.size ?: 0
                             }
-                            resultsCount?.add(countResultSize)
                         }
-                    }
-                    // make a singleton list if all results are empty.
-                    if (resultsCount?.sum() == 0) {
-                        resultsCount = mutableListOf(0)
+                        countsPerLanguageCode.add(langCode to countResultSize)
                     }
                 }