fix: mentions detection - android (#200)

Fixes:
#199

Author: exploIF

android/src/main/java/com/swmansion/enriched/EnrichedTextInputView.kt

@@ -51,7 +51,10 @@ class EnrichedTextInputView : AppCompatEditText {
   val paragraphStyles: ParagraphStyles? = ParagraphStyles(this)
   val listStyles: ListStyles? = ListStyles(this)
   val parametrizedStyles: ParametrizedStyles? = ParametrizedStyles(this)
-  var isSettingValue: Boolean = false
+  // Sometimes setting up style triggers many changes in sequence
+  // Eg. removing conflicting styles -> changing text -> applying spans
+  // In such scenario we want to prevent from handling side effects (eg. onTextChanged)
+  var isDuringTransaction: Boolean = false
   var isRemovingMany: Boolean = false
 
   val mentionHandler: MentionHandler? = MentionHandler(this)
@@ -233,7 +236,7 @@ class EnrichedTextInputView : AppCompatEditText {
 
   fun setValue(value: CharSequence?) {
     if (value == null) return
-    isSettingValue = true
+    isDuringTransaction = true
 
     val newText = parseText(value)
     setText(newText)
@@ -244,7 +247,7 @@ class EnrichedTextInputView : AppCompatEditText {
     // Scroll to the last line of text
     setSelection(text?.length ?: 0)
 
-    isSettingValue = false
+    isDuringTransaction = false
   }
 
   fun setAutoFocus(autoFocus: Boolean) {
@@ -452,13 +455,13 @@ class EnrichedTextInputView : AppCompatEditText {
       val end = selection?.end ?: 0
       val lengthBefore = text?.length ?: 0
 
-      isSettingValue = true
+      isDuringTransaction = true
       val targetRange = getTargetRange(name)
       val removed = removeStyle(style, targetRange.first, targetRange.second)
       if (removed) {
         spanState?.setStart(style, null)
       }
-      isSettingValue = false
+      isDuringTransaction = false
 
       val lengthAfter = text?.length ?: 0
       val charactersRemoved = lengthBefore - lengthAfter

android/src/main/java/com/swmansion/enriched/events/MentionHandler.kt

@@ -8,6 +8,11 @@ class MentionHandler(private val view: EnrichedTextInputView) {
   private var previousText: String? = null
   private var previousIndicator: String? = null
 
+  fun reset() {
+    previousText = null
+    previousIndicator = null
+  }
+
   fun endMention() {
     val indicator = previousIndicator
     if (indicator == null) return

android/src/main/java/com/swmansion/enriched/styles/ParametrizedStyles.kt

@@ -201,6 +201,7 @@ class ParametrizedStyles(private val view: EnrichedTextInputView) {
     }
 
     val start = mentionStart ?: return
+    view.isDuringTransaction = true
     spannable.replace(start, selectionEnd, text)
 
     val span = EnrichedMentionSpan(text, indicator, attributes, view.htmlStyle)
@@ -213,6 +214,8 @@ class ParametrizedStyles(private val view: EnrichedTextInputView) {
       spannable.insert(safeEnd, " ")
     }
 
+    view.isDuringTransaction = false
+    view.mentionHandler?.reset()
     view.selection.validateStyles()
   }
 

android/src/main/java/com/swmansion/enriched/utils/EnrichedSelection.kt

@@ -39,7 +39,7 @@ class EnrichedSelection(private val view: EnrichedTextInputView) {
     val finalStart = newStart.coerceAtMost(newEnd).coerceAtLeast(0).coerceAtMost(textLength)
     val finalEnd = newEnd.coerceAtLeast(newStart).coerceAtLeast(0).coerceAtMost(textLength)
 
-    if (isZeroWidthSelection(finalStart, finalEnd) && !view.isSettingValue) {
+    if (isZeroWidthSelection(finalStart, finalEnd) && !view.isDuringTransaction) {
       view.setSelection(finalStart + 1)
       shouldValidateStyles = false
     }

android/src/main/java/com/swmansion/enriched/watchers/EnrichedTextWatcher.kt

@@ -18,14 +18,14 @@ class EnrichedTextWatcher(private val view: EnrichedTextInputView) : TextWatcher
   override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
     endCursorPosition = start + count
     view.layoutManager.measureSize(s ?: "")
-    view.isRemovingMany = !view.isSettingValue && before > count + 1
+    view.isRemovingMany = !view.isDuringTransaction && before > count + 1
   }
 
   override fun afterTextChanged(s: Editable?) {
     if (s == null) return
     emitEvents(s)
 
-    if (view.isSettingValue) return
+    if (view.isDuringTransaction) return
     applyStyles(s)
   }
 

example/src/App.tsx

@@ -149,7 +149,14 @@ export default function App() {
   };
 
   const handleStartMention = (indicator: string) => {
-    indicator === '@' ? openUserMentionPopup() : openChannelMentionPopup();
+    if (indicator === '@') {
+      userMention.onMentionChange('');
+      openUserMentionPopup();
+      return;
+    }
+
+    channelMention.onMentionChange('');
+    openChannelMentionPopup();
   };
 
   const handleEndMention = (indicator: string) => {