From b01d0bfd826536dce6b4f40d9ebfb69b5ea36377 Mon Sep 17 00:00:00 2001
From: "Andrei.Salavei" <andrei.salavei@jetbrains.com>
Date: Thu, 21 Dec 2023 18:07:45 +0100
Subject: [PATCH] Fix keyboard disappearing while switching between text fields

---
 .../platform/UIKitTextInputService.uikit.kt   | 12 +++++++-
 .../compose/ui/window/FocusStack.uikit.kt     | 28 ++++++++++++-------
 .../IntermediateTextInputUIView.uikit.kt.kt   |  9 ++++++
 3 files changed, 38 insertions(+), 11 deletions(-)

diff --git a/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/platform/UIKitTextInputService.uikit.kt b/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/platform/UIKitTextInputService.uikit.kt
index c825f6da013b2..0107e6bba9b09 100644
--- a/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/platform/UIKitTextInputService.uikit.kt
+++ b/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/platform/UIKitTextInputService.uikit.kt
@@ -31,6 +31,8 @@ import org.jetbrains.skia.BreakIterator
 import org.jetbrains.skiko.SkikoKey
 import org.jetbrains.skiko.SkikoKeyboardEventKind
 import platform.UIKit.*
+import platform.darwin.dispatch_async
+import platform.darwin.dispatch_get_main_queue
 
 internal class UIKitTextInputService(
     private val updateView: () -> Unit,
@@ -106,6 +108,7 @@ internal class UIKitTextInputService(
         currentImeOptions = imeOptions
         currentImeActionHandler = onImeActionPerformed
 
+        textUIView?.removeFromSuperview()
         textUIView = IntermediateTextInputUIView(
             keyboardEventHandler = keyboardEventHandler,
         ).also {
@@ -127,7 +130,14 @@ internal class UIKitTextInputService(
         currentImeOptions = null
         currentImeActionHandler = null
         hideSoftwareKeyboard()
-        textUIView?.removeFromSuperview()
+
+        textUIView?.input = null
+        textUIView?.let { view ->
+
+            dispatch_async(dispatch_get_main_queue()) {
+                view.removeFromSuperview()
+            }
+        }
         textUIView = null
     }
 
diff --git a/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/FocusStack.uikit.kt b/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/FocusStack.uikit.kt
index ff1efcc5845fa..cff63aac76a06 100644
--- a/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/FocusStack.uikit.kt
+++ b/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/FocusStack.uikit.kt
@@ -18,6 +18,8 @@ package androidx.compose.ui.window
 
 import androidx.compose.ui.util.fastForEachReversed
 import platform.UIKit.UIView
+import platform.darwin.dispatch_async
+import platform.darwin.dispatch_get_main_queue
 
 /**
  * Stack to remember previously focused UIView.
@@ -43,24 +45,30 @@ internal interface FocusStack<V> {
 
 internal class FocusStackImpl : FocusStack<UIView> {
 
-    private var list = emptyList<UIView>()
+    private var activeViews = emptyList<UIView>()
+    private var resignedViews = emptyList<UIView>()
 
     override fun pushAndFocus(view: UIView) {
-        list += view
+        activeViews += view
+        resignedViews -= view
         view.becomeFirstResponder()
     }
 
     override fun popUntilNext(view: UIView) {
-        if (list.contains(view)) {
-            val index = list.indexOf(view)
-            list.subList(index, list.lastIndex).fastForEachReversed {
-                it.resignFirstResponder()
+        if (activeViews.contains(view)) {
+            val index = activeViews.indexOf(view)
+            resignedViews += activeViews.subList(index, activeViews.lastIndex)
+            activeViews = activeViews.subList(0, index)
+
+            dispatch_async(dispatch_get_main_queue()) {
+                resignedViews.fastForEachReversed {
+                    it.resignFirstResponder()
+                }
+                resignedViews = emptyList()
+                activeViews.lastOrNull()?.becomeFirstResponder()
             }
-            list = list.subList(0, index)
-            list.lastOrNull()?.becomeFirstResponder()
         }
     }
 
-    override fun first(): UIView? = list.firstOrNull()
-
+    override fun first(): UIView? = activeViews.firstOrNull()
 }
diff --git a/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/IntermediateTextInputUIView.uikit.kt.kt b/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/IntermediateTextInputUIView.uikit.kt.kt
index 2ea535cbeb8b1..90cbd07038cbd 100644
--- a/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/IntermediateTextInputUIView.uikit.kt.kt
+++ b/compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/IntermediateTextInputUIView.uikit.kt.kt
@@ -39,6 +39,7 @@ import platform.Foundation.NSSelectorFromString
 import platform.Foundation.dictionary
 import platform.UIKit.NSWritingDirection
 import platform.UIKit.NSWritingDirectionLeftToRight
+import platform.UIKit.UIEvent
 import platform.UIKit.UIKeyInputProtocol
 import platform.UIKit.UIKeyboardAppearance
 import platform.UIKit.UIKeyboardType
@@ -93,6 +94,14 @@ internal class IntermediateTextInputUIView(
         super.pressesEnded(presses, withEvent)
     }
 
+    override fun hitTest(point: CValue<CGPoint>, withEvent: UIEvent?): UIView? {
+        return if (input == null) {
+            null
+        } else {
+            super.hitTest(point, withEvent)
+        }
+    }
+
     /**
      * A Boolean value that indicates whether the text-entry object has any text.
      * https://developer.apple.com/documentation/uikit/uikeyinput/1614457-hastext