feat: enable highlight effect for unrolled candidates

app/src/main/java/com/osfans/trime/ime/bar/QuickBar.kt

@@ -178,6 +178,13 @@ class QuickBar(
     val unrollButtonStateMachine =
         UnrollButtonStateMachine.new {
             when (it) {
+                UnrollButtonStateMachine.State.AboutToAttachWindow -> {
+                    setUnrollButtonToDetach()
+                    setUnrollButtonEnabled(true)
+                    windowManager.attachWindow(
+                        FlexboxUnrolledCandidateWindow(context, service, rime, theme, this, windowManager, candidate),
+                    )
+                }
                 UnrollButtonStateMachine.State.ClickToAttachWindow -> {
                     setUnrollButtonToAttach()
                     setUnrollButtonEnabled(true)
@@ -193,7 +200,7 @@ class QuickBar(
         }
 
     private fun setUnrollButtonToAttach() {
-        candidateUi.unrollButton.setOnClickListener { view ->
+        candidateUi.unrollButton.setOnClickListener {
             windowManager.attachWindow(
                 FlexboxUnrolledCandidateWindow(context, service, rime, theme, this, windowManager, candidate),
             )
@@ -202,7 +209,7 @@ class QuickBar(
     }
 
     private fun setUnrollButtonToDetach() {
-        candidateUi.unrollButton.setOnClickListener { view ->
+        candidateUi.unrollButton.setOnClickListener {
             windowManager.attachWindow(KeyboardWindow)
         }
         candidateUi.unrollButton.setIcon(R.drawable.ic_baseline_expand_less_24)

app/src/main/java/com/osfans/trime/ime/bar/UnrollButtonStateMachine.kt

@@ -5,6 +5,8 @@
 package com.osfans.trime.ime.bar
 
 import com.osfans.trime.ime.bar.UnrollButtonStateMachine.BooleanKey.UnrolledCandidatesEmpty
+import com.osfans.trime.ime.bar.UnrollButtonStateMachine.BooleanKey.UnrolledCandidatesHighlighted
+import com.osfans.trime.ime.bar.UnrollButtonStateMachine.State.AboutToAttachWindow
 import com.osfans.trime.ime.bar.UnrollButtonStateMachine.State.ClickToAttachWindow
 import com.osfans.trime.ime.bar.UnrollButtonStateMachine.State.ClickToDetachWindow
 import com.osfans.trime.ime.bar.UnrollButtonStateMachine.State.Hidden
@@ -14,13 +16,15 @@ import com.osfans.trime.util.TransitionBuildBlock
 
 object UnrollButtonStateMachine {
     enum class State {
+        AboutToAttachWindow,
         ClickToAttachWindow,
         ClickToDetachWindow,
         Hidden,
     }
 
     enum class BooleanKey : EventStateMachine.BooleanStateKey {
         UnrolledCandidatesEmpty,
+        UnrolledCandidatesHighlighted,
     }
 
     enum class TransitionEvent(
@@ -29,9 +33,11 @@ object UnrollButtonStateMachine {
         UnrolledCandidatesUpdated({
             from(Hidden) transitTo ClickToAttachWindow on (UnrolledCandidatesEmpty to false)
             from(ClickToAttachWindow) transitTo Hidden on (UnrolledCandidatesEmpty to true)
+            from(ClickToAttachWindow) transitTo AboutToAttachWindow on (UnrolledCandidatesHighlighted to true)
         }),
         UnrolledCandidatesAttached({
             from(ClickToAttachWindow) transitTo ClickToDetachWindow
+            from(AboutToAttachWindow) transitTo ClickToDetachWindow
         }),
         UnrolledCandidatesDetached({
             from(ClickToDetachWindow) transitTo Hidden on (UnrolledCandidatesEmpty to true)

app/src/main/java/com/osfans/trime/ime/candidates/CandidateItemUi.kt

@@ -4,6 +4,7 @@
 
 package com.osfans.trime.ime.candidates
 
+import android.annotation.SuppressLint
 import android.content.Context
 import android.graphics.drawable.ColorDrawable
 import android.view.View
@@ -122,19 +123,20 @@ class CandidateItemUi(
         )
     }
 
+    @SuppressLint("UseKtx")
     fun update(
         item: CandidateItem,
-        isHighlighted: Boolean,
+        highlighted: Boolean,
     ) {
-        val tColor = if (isHighlighted) hlTextColor else textColor
-        val cColor = if (isHighlighted) hlCommentColor else commentColor
+        val tColor = if (highlighted) hlTextColor else textColor
+        val cColor = if (highlighted) hlCommentColor else commentColor
         text.text = item.text
         text.setTextColor(tColor)
         comment.text = if (theme.generalStyle.commentOnTop) item.comment else " ${item.comment}"
         comment.setTextColor(cColor)
         comment.isGone = item.comment.isEmpty()
         root.background =
-            if (isHighlighted) {
+            if (highlighted) {
                 ColorDrawable(hlBackColor)
             } else {
                 pressHighlightDrawable(hlBackColor)

app/src/main/java/com/osfans/trime/ime/candidates/compact/CompactCandidateModule.kt

@@ -62,11 +62,16 @@ class CompactCandidateModule(
             UnrollButtonStateMachine.BooleanKey.UnrolledCandidatesEmpty to
                 (adapter.total == childCount),
         )
+        bar.unrollButtonStateMachine.push(
+            UnrollButtonStateMachine.TransitionEvent.UnrolledCandidatesUpdated,
+            UnrollButtonStateMachine.BooleanKey.UnrolledCandidatesHighlighted to
+                (adapter.highlightedIdx >= childCount),
+        )
     }
 
     val adapter by lazy {
         CompactCandidateViewAdapter(theme).apply {
-            setOnItemClickListener { _, view, position ->
+            setOnItemClickListener { _, _, position ->
                 rime.launchOnReady { it.selectCandidate(position, global = true) }
             }
             setOnItemLongClickListener { _, view, position ->

app/src/main/java/com/osfans/trime/ime/candidates/unrolled/PagingCandidateViewAdapter.kt

@@ -34,8 +34,12 @@ open class PagingCandidateViewAdapter(
     var offset: Int = 0
         private set
 
-    fun refreshWithOffset(offset: Int) {
+    var highlightedIndex: Int = -1
+        private set
+
+    fun refreshWith(offset: Int, highlightedIndex: Int) {
         this.offset = offset
+        this.highlightedIndex = highlightedIndex
         refresh()
     }
 
@@ -49,9 +53,11 @@ open class PagingCandidateViewAdapter(
         position: Int,
     ) {
         val item = getItem(position) ?: return
-        holder.ui.update(item, false)
+        val idx = position + offset
+        val highlighted = idx == highlightedIndex
+        holder.ui.update(item, highlighted)
         holder.text = item.text
         holder.comment = item.comment
-        holder.idx = position + offset
+        holder.idx = idx
     }
 }

app/src/main/java/com/osfans/trime/ime/candidates/unrolled/window/BaseUnrolledCandidateWindow.kt

@@ -106,7 +106,10 @@ abstract class BaseUnrolledCandidateWindow(
                         windowManager.attachWindow(KeyboardWindow)
                     } else {
                         candidateLayout.resetPosition()
-                        adapter.refreshWithOffset(it)
+                        adapter.refreshWith(
+                            offset = it,
+                            highlightedIndex = compactCandidate.adapter.highlightedIdx,
+                        )
                     }
                 }
             }
@@ -120,7 +123,7 @@ abstract class BaseUnrolledCandidateWindow(
 
     fun bindCandidateUiViewHolder(holder: CandidateViewHolder) {
         holder.itemView.run {
-            setOnClickListener { view ->
+            setOnClickListener { _ ->
                 rime.launchOnReady { it.selectCandidate(holder.idx, global = true) }
             }
             setOnLongClickListener { view ->