Remove `NativeAccessibleFocusHelper` (#1147)

skiko/src/awtMain/kotlin/org/jetbrains/skiko/Accessibility.kt

 package org.jetbrains.skiko
 
-import kotlinx.coroutines.*
-import java.awt.Component
-import java.awt.KeyboardFocusManager
-import java.awt.event.FocusEvent
-import java.beans.PropertyChangeEvent
 import javax.accessibility.Accessible
-import javax.accessibility.AccessibleContext
 
 /**
- * See [nativeInitializeAccessible] doc for details
+ * Calls `sun.lwawt.macosx.CAccessible.getCAccessible(Accessible)` on the given [accessible] object; does nothing
+ * if running on a non-Mac platform or in a JVM where there is no `CAccessible` class.
+ *
+ * Ideally, this and nativeInitializeAccessible should be in Compose, not Skiko.
+ * Unfortunately, Compose doesn't currently allow native code, and implementing it via reflection is not
+ * possible due to java.desktop module access restrictions:
+ * > class androidx.compose.ui.platform.a11y.AccessibilityKt cannot access class sun.lwawt.macosx.CAccessible
+ * > (in module java.desktop) because module java.desktop does not export sun.lwawt.macosx to unnamed module
+ *
+ * As such, this function is not to be considered public Skiko API.
  */
-internal external fun initializeCAccessible(accessible: Accessible)
-
-/**
- * A helper class for implementing requesting accessibility focus on a given accessible.
- */
-internal class NativeAccessibleFocusHelper(
-    private val component: Component,
-    private val externalAccessible: Accessible?,
-) {
-
-    private var focusedAccessible: Accessible? = null
-
-    val accessibleContext: AccessibleContext?
-        get() = (focusedAccessible ?: externalAccessible)?.accessibleContext
-
-    private var resetFocusAccessibleJob: Job? = null
-
-    @OptIn(DelicateCoroutinesApi::class)
-    fun requestNativeFocusOnAccessible(accessible: Accessible?) {
-        focusedAccessible = accessible
-
-        when (hostOs) {
-            OS.Windows -> requestAccessBridgeFocusOnAccessible()
-            OS.MacOS -> requestMacOSFocusOnAccessible(accessible)
-            else -> {
-                focusedAccessible = null
-                return
-            }
-        }
-
-        // Listener spawns asynchronous notification post procedure, reading current focus owner
-        // and its accessibility context. This timeout is used to deal with concurrency
-        // TODO Find more reliable procedure
-        resetFocusAccessibleJob?.cancel()
-        resetFocusAccessibleJob = GlobalScope.launch(MainUIDispatcher) {
-            delay(100)
-            focusedAccessible = null
-        }
-    }
-
-    private fun requestAccessBridgeFocusOnAccessible() {
-        val focusEvent = FocusEvent(component, FocusEvent.FOCUS_GAINED)
-        component.focusListeners.forEach { it.focusGained(focusEvent) }
-    }
-
-    private fun requestMacOSFocusOnAccessible(accessible: Accessible?) {
-        val focusManager = KeyboardFocusManager.getCurrentKeyboardFocusManager()
-        val listeners = focusManager.getPropertyChangeListeners("focusOwner")
-        val event = PropertyChangeEvent(focusManager, "focusOwner", null, accessible)
-        listeners.forEach { it.propertyChange(event) }
-    }
-
-    fun dispose() {
-        resetFocusAccessibleJob?.cancel()
-    }
-}
\ No newline at end of file
+external fun initializeCAccessible(accessible: Accessible)

skiko/src/awtMain/kotlin/org/jetbrains/skiko/HardwareLayer.kt

@@ -7,11 +7,10 @@ import java.awt.Canvas
 import java.awt.Component
 import java.awt.Graphics
 import java.awt.event.InputMethodEvent
-import javax.accessibility.Accessible
 import javax.accessibility.AccessibleContext
 
 internal open class HardwareLayer(
-    externalAccessibleFactory: ((Component) -> Accessible)? = null
+    private val accessibleContextProvider: ((Component) -> AccessibleContext)? = null
 ) : Canvas() {
     companion object {
         init {
@@ -26,7 +25,6 @@ internal open class HardwareLayer(
     }
 
     open fun dispose() {
-        nativeAccessibleFocusHelper.dispose()
         nativeDispose()
     }
 
@@ -58,18 +56,8 @@ internal open class HardwareLayer(
     private external fun getWindowHandle(platformInfo: Long): Long
     private external fun getCurrentDPI(platformInfo: Long): Int
 
-    @Suppress("LeakingThis")
-    private val nativeAccessibleFocusHelper = NativeAccessibleFocusHelper(
-        component = this,
-        externalAccessible = externalAccessibleFactory?.invoke(this)
-    )
-
     override fun getAccessibleContext(): AccessibleContext {
-        return nativeAccessibleFocusHelper.accessibleContext ?: super.getAccessibleContext()
-    }
-
-    fun requestNativeFocusOnAccessible(accessible: Accessible?) {
-        nativeAccessibleFocusHelper.requestNativeFocusOnAccessible(accessible)
+        return accessibleContextProvider?.invoke(this) ?: super.getAccessibleContext()
     }
 }
 
@@ -106,29 +94,3 @@ internal fun layerFrameLimiter(
         }
     )
 }
-
-/**
- * This method should be called on custom [Accessible] creation (or its context if context is created lazily).
- *
- * JDK's accessibility support (at least for MacOS) builds mapping AccessibleContext -> Accessible.
- * Some [Accessible] are built only when focus is settled and
- * since we have a hack [NativeAccessibleFocusHelper.requestNativeFocusOnAccessible], wrong mapping can be built
- * (ComponentAccessibleContext -> SkiaLayer instead of ComponentAccessibleContext -> ComponentAccessible).
- *
- * This method forces JDK's accessibility support to cache mapping ComponentAccessibleContext -> ComponentAccessible,
- * if it is called on ComponentAccessibleContext creation.
- *
- * Related to the [issue](https://youtrack.jetbrains.com/issue/COMPOSE-176).
- */
-@Suppress("unused")
-fun nativeInitializeAccessible(accessible: Accessible) {
-    when (hostOs) {
-        OS.MacOS -> {
-            initializeCAccessible(accessible)
-        }
-
-        else -> {
-            // TODO: do we need something for Windows?
-        }
-    }
-}
\ No newline at end of file

skiko/src/awtMain/kotlin/org/jetbrains/skiko/SkiaLayer.awt.kt

@@ -27,7 +27,7 @@ import javax.swing.event.AncestorListener
 import kotlin.math.floor
 
 actual open class SkiaLayer internal constructor(
-    externalAccessibleFactory: ((Component) -> Accessible)? = null,
+    accessibleContextProvider: ((Component) -> AccessibleContext)? = null,
     val properties: SkiaLayerProperties,
     private val renderFactory: RenderFactory = RenderFactory.Default,
     private val analytics: SkiaLayerAnalytics = SkiaLayerAnalytics.Empty,
@@ -48,7 +48,7 @@ actual open class SkiaLayer internal constructor(
     internal val backedLayer: HardwareLayer
 
     constructor(
-        externalAccessibleFactory: ((Component) -> Accessible)? = null,
+        accessibleContextProvider: ((Component) -> AccessibleContext)? = null,
         isVsyncEnabled: Boolean = SkikoProperties.vsyncEnabled,
         isVsyncFramelimitFallbackEnabled: Boolean = SkikoProperties.vsyncFramelimitFallbackEnabled,
         frameBuffering: FrameBuffering = SkikoProperties.frameBuffering,
@@ -56,7 +56,7 @@ actual open class SkiaLayer internal constructor(
         analytics: SkiaLayerAnalytics = SkiaLayerAnalytics.Empty,
         pixelGeometry: PixelGeometry = PixelGeometry.UNKNOWN,
     ) : this(
-        externalAccessibleFactory,
+        accessibleContextProvider,
         SkiaLayerProperties(
             isVsyncEnabled,
             isVsyncFramelimitFallbackEnabled,
@@ -69,12 +69,12 @@ actual open class SkiaLayer internal constructor(
     )
 
     constructor(
-        externalAccessibleFactory: ((Component) -> Accessible)? = null,
+        accessibleContextProvider: ((Component) -> AccessibleContext)? = null,
         properties: SkiaLayerProperties,
         analytics: SkiaLayerAnalytics = SkiaLayerAnalytics.Empty,
         pixelGeometry: PixelGeometry = PixelGeometry.UNKNOWN,
     ) : this(
-        externalAccessibleFactory,
+        accessibleContextProvider,
         properties,
         RenderFactory.Default,
         analytics,
@@ -89,7 +89,7 @@ actual open class SkiaLayer internal constructor(
 
     init {
         layout = null
-        backedLayer = object : HardwareLayer(externalAccessibleFactory) {
+        backedLayer = object : HardwareLayer(accessibleContextProvider) {
             override fun paint(g: Graphics) {
                 Logger.debug { "Paint called on HardwareLayer $this" }
                 checkContentScale()
@@ -683,10 +683,6 @@ actual open class SkiaLayer internal constructor(
         }
     }
 
-    fun requestNativeFocusOnAccessible(accessible: Accessible?) {
-        backedLayer.requestNativeFocusOnAccessible(accessible)
-    }
-
     override fun getAccessibleContext(): AccessibleContext {
         if (accessibleContext == null) {
             accessibleContext = AccessibleSkiaLayer()

skiko/src/awtMain/kotlin/org/jetbrains/skiko/swing/SkiaSwingLayer.kt

@@ -7,7 +7,6 @@ import java.awt.Component
 import java.awt.Graphics
 import java.awt.Graphics2D
 import java.awt.GraphicsConfiguration
-import javax.accessibility.Accessible
 import javax.accessibility.AccessibleContext
 import javax.swing.JPanel
 import javax.swing.SwingUtilities.isEventDispatchThread
@@ -27,7 +26,7 @@ import javax.swing.SwingUtilities.isEventDispatchThread
 open class SkiaSwingLayer(
     renderDelegate: SkikoRenderDelegate,
     analytics: SkiaLayerAnalytics = SkiaLayerAnalytics.Empty,
-    externalAccessibleFactory: ((Component) -> Accessible)? = null,
+    private val accessibleContextProvider: ((Component) -> AccessibleContext)? = null,
     private val properties: SkiaLayerProperties = SkiaLayerProperties()
 ) : JPanel() {
     internal companion object {
@@ -126,17 +125,7 @@ open class SkiaSwingLayer(
         }
     }
 
-    @Suppress("LeakingThis")
-    private val nativeAccessibleFocusHelper = NativeAccessibleFocusHelper(
-        component = this,
-        externalAccessible = externalAccessibleFactory?.invoke(this)
-    )
-
     override fun getAccessibleContext(): AccessibleContext? {
-        return nativeAccessibleFocusHelper.accessibleContext ?: super.getAccessibleContext()
-    }
-
-    fun requestNativeFocusOnAccessible(accessible: Accessible?) {
-        nativeAccessibleFocusHelper.requestNativeFocusOnAccessible(accessible)
+        return accessibleContextProvider?.invoke(this) ?: super.getAccessibleContext()
     }
 }