Compose UI for Linux

Author: Thomas-Vos

buildSrc/src/main/kotlin/ComposePlatforms.kt

@@ -111,7 +111,7 @@ enum class ComposePlatforms(vararg val alternativeNames: String) {
         val GENERATE_KLIB = WEB + LINUX_NATIVE + WINDOWS_NATIVE + DARWIN
 
         val SKIKO_SUPPORT =
-            EnumSet.of(KotlinMultiplatform) + JVM_BASED + UI_KIT + MACOS_NATIVE + WEB
+            EnumSet.of(KotlinMultiplatform) + JVM_BASED + UI_KIT + MACOS_NATIVE + LINUX_NATIVE + WEB
 
         val ALL = EnumSet.allOf(ComposePlatforms::class.java) - IOS
         val ALL_AOSP = EnumSet.allOf(ComposePlatforms::class.java) - UI_KIT

compose/animation/animation-core/build.gradle

@@ -74,6 +74,7 @@ if (AndroidXComposePlugin.isMultiplatformEnabled(project)) {
         darwin()
         js()
         wasm()
+        linux()
     }
 
     kotlin {

compose/animation/animation-graphics/build.gradle

@@ -71,6 +71,7 @@ if(AndroidXComposePlugin.isMultiplatformEnabled(project)) {
         darwin()
         js()
         wasm()
+        linux()
     }
 
     kotlin {

compose/animation/animation/build.gradle

@@ -72,6 +72,7 @@ if(AndroidXComposePlugin.isMultiplatformEnabled(project)) {
         darwin()
         js()
         wasm()
+        linux()
     }
 
     kotlin {

compose/foundation/foundation-layout/build.gradle

@@ -78,6 +78,7 @@ if(AndroidXComposePlugin.isMultiplatformEnabled(project)) {
         darwin()
         js()
         wasm()
+        linux()
     }
 
     kotlin {
@@ -122,6 +123,7 @@ if(AndroidXComposePlugin.isMultiplatformEnabled(project)) {
             desktopMain.dependsOn(notMobileMain)
             macosMain.dependsOn(notMobileMain)
             jsWasmMain.dependsOn(notMobileMain)
+            linuxMain.dependsOn(notMobileMain)
 
             jsMain {
                 dependsOn(jsWasmMain)

compose/foundation/foundation/build.gradle

@@ -94,6 +94,7 @@ if (AndroidXComposePlugin.isMultiplatformEnabled(project)) {
         darwin()
         js()
         wasm()
+        linux()
 
         configureDarwinFlags()
     }

compose/foundation/foundation/src/linuxMain/kotlin/androidx/compose/foundation/Clickable.linux.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.foundation
+
+// TODO: b/168524931 - should this depend on the input device?
+internal actual val TapIndicationDelay: Long = 0L

compose/foundation/foundation/src/linuxMain/kotlin/androidx/compose/foundation/Overscroll.linux.kt

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.foundation
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalAccessorScope
+
+@Composable
+internal actual fun rememberPlatformOverscrollEffect(): OverscrollEffect? =
+    null
+
+internal actual fun CompositionLocalAccessorScope.defaultOverscrollFactory(): OverscrollFactory? =
+    null

compose/foundation/foundation/src/linuxMain/kotlin/androidx/compose/foundation/RequestFocusOnClick.linux.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.foundation
+
+internal actual fun isRequestFocusOnClickEnabled(): Boolean = true

compose/foundation/foundation/src/linuxMain/kotlin/androidx/compose/foundation/gestures/LinuxScrollable.linux.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package androidx.compose.foundation.gestures
+
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.input.pointer.PointerEvent
+import androidx.compose.ui.node.CompositionLocalConsumerModifierNode
+import androidx.compose.ui.unit.Density
+import androidx.compose.ui.unit.IntSize
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.util.fastFold
+import kotlin.math.sqrt
+
+internal actual fun CompositionLocalConsumerModifierNode.platformScrollConfig(): ScrollConfig =
+    LinuxScrollConfig
+
+private object LinuxScrollConfig : ScrollConfig {
+    // See https://developer.apple.com/documentation/appkit/nsevent/1535387-scrollingdeltay
+    override fun Density.calculateMouseWheelScroll(event: PointerEvent, bounds: IntSize): Offset {
+        // 64 dp value is taken from ViewConfiguration.java, replace with better solution
+
+        val verticalScrollFactor = -64.dp.toPx()
+
+        val horizontalScrollFactor = -64.dp.toPx()
+
+        return event.changes
+            .fastFold(Offset.Zero) { acc, c -> acc + c.scrollDelta }
+            .let { Offset(it.x * horizontalScrollFactor, it.y * verticalScrollFactor) }
+    }
+}