Swing interop: off-screen rendering on graphics

compose/desktop/desktop/samples/build.gradle

@@ -90,6 +90,16 @@ task runSwing(type: JavaExec) {
         compilation.runtimeDependencyFiles
 }
 
+task runSwingOffscreenRendering(type: JavaExec) {
+    dependsOn(":compose:desktop:desktop:jar")
+    main = "androidx.compose.desktop.examples.swingexample.Main_jvmKt"
+    def compilation = kotlin.jvm().compilations["main"]
+    classpath =
+            compilation.output.allOutputs +
+                    compilation.runtimeDependencyFiles
+    jvmArgs("-Dcompose.swing.render.on.graphics=true")
+}
+
 task runMouseClicks(type: JavaExec) {
     dependsOn(":compose:desktop:desktop:jar")
     main = "androidx.compose.desktop.examples.mouseclicks.Main_jvmKt"

compose/desktop/desktop/samples/src/jvmMain/kotlin/androidx/compose/desktop/examples/swingexample/Main.jvm.kt

@@ -143,6 +143,8 @@ fun SwingComposeWindow() {
             size = IntSize(40, 40),
             action = {
                 panel.remove(composePanelBottom)
+                panel.revalidate()
+                panel.repaint()
             }
         ),
         BorderLayout.SOUTH

compose/ui/ui/src/desktopMain/kotlin/androidx/compose/ui/awt/ComposeLayer.desktop.kt

@@ -56,7 +56,7 @@ import org.jetbrains.skiko.*
  *
  * Inheritors should call [attachComposeToComponent], so events that came to [component] will be transferred to [ComposeScene]
  */
-internal abstract class ComposeLayer {
+internal abstract class ComposeBridge {
     private var isDisposed = false
 
     val sceneAccessible = ComposeSceneAccessible(

compose/ui/ui/src/desktopMain/kotlin/androidx/compose/ui/awt/ComposePanel.desktop.kt

@@ -23,7 +23,6 @@ import androidx.compose.ui.window.WindowExceptionHandler
 import java.awt.*
 import java.awt.event.FocusEvent
 import java.awt.event.FocusListener
-import javax.swing.JComponent
 import javax.swing.JLayeredPane
 import javax.swing.SwingUtilities.isEventDispatchThread
 import org.jetbrains.skiko.ClipComponent
@@ -74,7 +73,7 @@ class ComposePanel @ExperimentalComposeUiApi constructor(
     private val _focusListeners = mutableSetOf<FocusListener?>()
     private var _isFocusable = true
     private var _isRequestFocusEnabled = false
-    private var layer: ComposeLayer? = null
+    private var layer: ComposeBridge? = null
     private val clipMap = mutableMapOf<Component, ClipComponent>()
     private var content: (@Composable () -> Unit)? = null
 
@@ -151,12 +150,12 @@ class ComposePanel @ExperimentalComposeUiApi constructor(
     }
 
     @OptIn(ExperimentalComposeUiApi::class)
-    private fun createComposeLayer(): ComposeLayer {
+    private fun createComposeLayer(): ComposeBridge {
         val renderOnGraphics = System.getProperty("compose.swing.render.on.graphics").toBoolean()
-        val layer: ComposeLayer = if (renderOnGraphics) {
-            ComposeSwingLayer(skiaLayerAnalytics)
+        val layer: ComposeBridge = if (renderOnGraphics) {
+            SwingComposeBridge(skiaLayerAnalytics)
         } else {
-            ComposeWindowLayer(skiaLayerAnalytics)
+            WindowComposeBridge(skiaLayerAnalytics)
         }
         return layer.apply {
             scene.releaseFocus()

compose/ui/ui/src/desktopMain/kotlin/androidx/compose/ui/awt/ComposeSwingLayer.desktop.kt

@@ -35,14 +35,53 @@ import org.jetbrains.skiko.swing.SkiaSwingLayer
  * Provides [component] that can be used as a Swing component.
  * Content set in [setContent] will be drawn on this [component].
  *
- * [ComposeSwingLayer] provides smooth integration with Swing, so z-ordering, double-buffering etc. from Swing will be taken into account.
+ * [SwingComposeBridge] provides smooth integration with Swing, so z-ordering, double-buffering etc. from Swing will be taken into account.
  *
- * However, if smooth interop with Swing is not needed, consider using [androidx.compose.ui.awt.ComposeWindowLayer]
+ * However, if smooth interop with Swing is not needed, consider using [androidx.compose.ui.awt.WindowComposeBridge]
  */
-internal class ComposeSwingLayer(
+internal class SwingComposeBridge(
     private val skiaLayerAnalytics: SkiaLayerAnalytics
-) : ComposeLayer() {
-    private val _component = ComposeSwingSkiaLayer()
+) : ComposeBridge() {
+    /**
+     * See also backendLayer for standalone Compose in [androidx.compose.ui.awt.WindowComposeBridge]
+     */
+    @OptIn(ExperimentalSkikoApi::class)
+    private val _component =
+        object : SkiaSwingLayer(skikoView = skikoView, analytics = skiaLayerAnalytics) {
+
+            override fun addNotify() {
+                super.addNotify()
+                resetSceneDensity()
+                initContent()
+                updateSceneSize()
+                setParentWindow(SwingUtilities.getWindowAncestor(this))
+            }
+
+            override fun removeNotify() {
+                setParentWindow(window = null)
+                super.removeNotify()
+            }
+
+            override fun paint(g: Graphics) {
+                resetSceneDensity()
+                super.paint(g)
+            }
+
+            override fun getInputMethodRequests() = currentInputMethodRequests
+
+            override fun doLayout() {
+                super.doLayout()
+                updateSceneSize()
+            }
+
+            override fun getPreferredSize(): Dimension {
+                return if (isPreferredSizeSet) super.getPreferredSize() else sceneDimension
+            }
+
+            override fun getAccessibleContext(): AccessibleContext? {
+                return sceneAccessible.accessibleContext
+            }
+        }
 
     @OptIn(ExperimentalSkikoApi::class)
     override val component: SkiaSwingLayer get() = _component
@@ -71,45 +110,4 @@ internal class ComposeSwingLayer(
     override fun disposeComponentLayer() {
         _component.dispose()
     }
-
-    /**
-     * See also backendLayer for standalone compose [androidx.compose.ui.awt.ComposeWindowLayer.ComposeWindowSkiaLayer]
-     */
-    @OptIn(ExperimentalSkikoApi::class)
-    private inner class ComposeSwingSkiaLayer :
-        SkiaSwingLayer(skikoView = skikoView, analytics = skiaLayerAnalytics) {
-
-        override fun addNotify() {
-            super.addNotify()
-            resetSceneDensity()
-            initContent()
-            updateSceneSize()
-            setParentWindow(SwingUtilities.getWindowAncestor(this))
-        }
-
-        override fun removeNotify() {
-            setParentWindow(window = null)
-            super.removeNotify()
-        }
-
-        override fun paint(g: Graphics) {
-            resetSceneDensity()
-            super.paint(g)
-        }
-
-        override fun getInputMethodRequests() = currentInputMethodRequests
-
-        override fun doLayout() {
-            super.doLayout()
-            updateSceneSize()
-        }
-
-        override fun getPreferredSize(): Dimension {
-            return if (isPreferredSizeSet) super.getPreferredSize() else sceneDimension
-        }
-
-        override fun getAccessibleContext(): AccessibleContext? {
-            return sceneAccessible.accessibleContext
-        }
-    }
 }

compose/ui/ui/src/desktopMain/kotlin/androidx/compose/ui/awt/ComposeWindowDelegate.desktop.kt

@@ -49,7 +49,7 @@ internal class ComposeWindowDelegate(
     // (see https://github.com/JetBrains/compose-jb/issues/1688),
     // so we nullify layer on dispose, to prevent keeping
     // big objects in memory (like the whole LayoutNode tree of the window)
-    private var _layer: ComposeWindowLayer? = ComposeWindowLayer(skiaLayerAnalytics)
+    private var _layer: WindowComposeBridge? = WindowComposeBridge(skiaLayerAnalytics)
     private val layer
         get() = requireNotNull(_layer) {
             "ComposeLayer is disposed"

compose/ui/ui/src/desktopMain/kotlin/androidx/compose/ui/awt/ComposeWindowLayer.kt → compose/ui/ui/src/desktopMain/kotlin/androidx/compose/ui/awt/WindowComposeBridge.kt

@@ -29,12 +29,50 @@ import org.jetbrains.skiko.SkiaLayerAnalytics
 /**
  * Provides a heavyweight AWT [component] used to render content (from [setContent]) on-screen with Skia.
  *
- * If smooth interop with Swing is needed, consider using [androidx.compose.ui.awt.ComposeWindowLayer]
+ * If smooth interop with Swing is needed, consider using [androidx.compose.ui.awt.SwingComposeBridge]
  */
-internal class ComposeWindowLayer(
+internal class WindowComposeBridge(
     private val skiaLayerAnalytics: SkiaLayerAnalytics
-) : ComposeLayer() {
-    private val _component = ComposeWindowSkiaLayer()
+) : ComposeBridge() {
+    /**
+     * See also backend layer for swing interop in [androidx.compose.ui.awt.SwingComposeBridge]
+     */
+    private val _component =
+        object : SkiaLayer(
+            externalAccessibleFactory = { sceneAccessible },
+            analytics = skiaLayerAnalytics
+        ), Accessible {
+
+            override fun addNotify() {
+                super.addNotify()
+                resetSceneDensity()
+                initContent()
+                updateSceneSize()
+                setParentWindow(SwingUtilities.getWindowAncestor(this))
+            }
+
+            override fun removeNotify() {
+                setParentWindow(null)
+                super.removeNotify()
+            }
+
+            override fun paint(g: Graphics) {
+                resetSceneDensity()
+                super.paint(g)
+            }
+
+            override fun getInputMethodRequests() = currentInputMethodRequests
+
+            override fun doLayout() {
+                super.doLayout()
+                updateSceneSize()
+            }
+
+            override fun getPreferredSize(): Dimension {
+                return if (isPreferredSizeSet) super.getPreferredSize() else sceneDimension
+            }
+        }
+
     override val component: SkiaLayer get() = _component
 
     override val renderApi: GraphicsApi
@@ -62,44 +100,4 @@ internal class ComposeWindowLayer(
     override fun disposeComponentLayer() {
         _component.dispose()
     }
-
-    /**
-     * See also backend layer for swing interop: [androidx.compose.ui.awt.ComposeSwingLayer.ComposeSwingSkiaLayer]
-     */
-    private inner class ComposeWindowSkiaLayer :
-        SkiaLayer(
-            externalAccessibleFactory = { sceneAccessible },
-            analytics = skiaLayerAnalytics
-        ),
-        Accessible {
-
-        override fun addNotify() {
-            super.addNotify()
-            resetSceneDensity()
-            initContent()
-            updateSceneSize()
-            setParentWindow(SwingUtilities.getWindowAncestor(this))
-        }
-
-        override fun removeNotify() {
-            setParentWindow(null)
-            super.removeNotify()
-        }
-
-        override fun paint(g: Graphics) {
-            resetSceneDensity()
-            super.paint(g)
-        }
-
-        override fun getInputMethodRequests() = currentInputMethodRequests
-
-        override fun doLayout() {
-            super.doLayout()
-            updateSceneSize()
-        }
-
-        override fun getPreferredSize(): Dimension {
-            return if (isPreferredSizeSet) super.getPreferredSize() else sceneDimension
-        }
-    }
 }