Forward UIViewController status bar APIs to ComposeUIViewControllerDelegate

compose/mpp/demo/src/uikitMain/kotlin/androidx/compose/mpp/demo/IosSpecificFeaturesExample.kt

@@ -53,5 +53,6 @@ val IosSpecificFeatures = Screen.Selection(
     HapticFeedbackExample,
     LazyColumnWithInteropViewsExample,
     AccessibilityLiveRegionExample,
-    InteropViewAndSemanticsConfigMerge
+    InteropViewAndSemanticsConfigMerge,
+    StatusBarStateExample
 )

compose/mpp/demo/src/uikitMain/kotlin/androidx/compose/mpp/demo/StatusBarState.kt

@@ -0,0 +1,124 @@
+/*
+ * 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.mpp.demo
+
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material.DropdownMenu
+import androidx.compose.material.DropdownMenuItem
+import androidx.compose.material.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.derivedStateOf
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.interop.LocalUIViewController
+import androidx.compose.ui.unit.dp
+import platform.UIKit.UIStatusBarAnimation
+import platform.UIKit.UIStatusBarStyleDarkContent
+import platform.UIKit.UIStatusBarStyleDefault
+import platform.UIKit.UIStatusBarStyleLightContent
+import platform.UIKit.UIView
+
+private var statusBarStyleIndex by mutableStateOf(0)
+val preferredStatusBarStyleValue by derivedStateOf { styleValues[statusBarStyleIndex].second }
+
+private var statusBarHiddenIndex by mutableStateOf(0)
+val prefersStatusBarHiddenValue by derivedStateOf { hiddenValues[statusBarHiddenIndex].second }
+
+private var statusBarAnimationIndex by mutableStateOf(0)
+val preferredStatysBarAnimationValue by derivedStateOf { animationValues[statusBarAnimationIndex].second }
+
+private val hiddenValues = listOf(
+    "null" to null,
+    "True" to true,
+    "False" to false
+)
+
+private val animationValues = listOf(
+    "null" to null,
+    "UIStatusBarAnimationFade" to UIStatusBarAnimation.UIStatusBarAnimationFade,
+    "UIStatusBarAnimationSlide" to UIStatusBarAnimation.UIStatusBarAnimationSlide
+)
+
+private val styleValues = listOf(
+    "null" to null,
+    "UIStatusBarStyleDefault" to UIStatusBarStyleDefault,
+    "UIStatusBarStyleLightContent" to UIStatusBarStyleLightContent,
+    "UIStatusBarStyleDarkContent" to UIStatusBarStyleDarkContent
+)
+
+val StatusBarStateExample = Screen.Example("StatusBarState") {
+    Column(modifier = Modifier.fillMaxSize()) {
+        Dropdown("preferredStatusBarStyle", styleValues[statusBarStyleIndex].first, styleValues.map { it.first }) {
+            statusBarStyleIndex = it
+        }
+
+        Dropdown("prefersStatusBarHidden", hiddenValues[statusBarHiddenIndex].first, hiddenValues.map { it.first }) {
+            statusBarHiddenIndex = it
+        }
+
+        Dropdown("preferredStatysBarAnimation", animationValues[statusBarAnimationIndex].first, animationValues.map { it.first }) {
+            statusBarAnimationIndex = it
+        }
+    }
+
+    val viewController = LocalUIViewController.current
+    LaunchedEffect(statusBarStyleIndex, statusBarHiddenIndex, statusBarAnimationIndex) {
+        UIView.animateWithDuration(0.3) {
+            viewController.setNeedsStatusBarAppearanceUpdate()
+        }
+    }
+}
+
+@Composable
+private fun Dropdown(
+    name: String,
+    current: String,
+    all: List<String>,
+    onSelected: (Int) -> Unit
+) {
+    var expanded by remember { mutableStateOf(false) }
+
+    Box(modifier = Modifier
+        .padding(16.dp)
+        .fillMaxWidth()
+        .clickable { expanded = true }) {
+        Text("$name: $current")
+
+        DropdownMenu(
+            expanded = expanded,
+            onDismissRequest = { expanded = false }) {
+            all.forEachIndexed { index, item ->
+                DropdownMenuItem(
+                    onClick = {
+                        onSelected(index)
+                        expanded = false
+                    }) {
+                    Text(item)
+                }
+            }
+        }
+    }
+}

compose/mpp/demo/src/uikitMain/kotlin/androidx/compose/mpp/demo/main.uikit.kt

@@ -11,6 +11,12 @@ import androidx.compose.ui.platform.AccessibilitySyncOptions
 import androidx.compose.ui.window.ComposeUIViewController
 import androidx.compose.mpp.demo.bugs.IosBugs
 import androidx.compose.mpp.demo.bugs.StartRecompositionCheck
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.uikit.ComposeUIViewControllerDelegate
+import platform.UIKit.UIStatusBarAnimation
+import platform.UIKit.UIStatusBarStyle
 import platform.UIKit.UIViewController
 
 @OptIn(ExperimentalComposeApi::class, ExperimentalComposeUiApi::class)
@@ -28,6 +34,17 @@ fun main(vararg args: String) {
                 }
             }
         })
+
+        delegate = object : ComposeUIViewControllerDelegate {
+            override val preferredStatusBarStyle: UIStatusBarStyle?
+                get() = preferredStatusBarStyleValue
+
+            override val prefersStatusBarHidden: Boolean?
+                get() = prefersStatusBarHiddenValue
+
+            override val preferredStatysBarAnimation: UIStatusBarAnimation?
+                get() = preferredStatysBarAnimationValue
+        }
     }) {
         IosDemo(arg)
     })

compose/ui/ui-uikit/src/uikitMain/objc/CMPUIKitUtils/CMPUIKitUtils/CMPViewController.h

@@ -28,6 +28,13 @@ NS_ASSUME_NONNULL_BEGIN
 /// Overriding classes should call super.
 - (void)viewControllerDidLeaveWindowHierarchy;
 
+
+// MARK: Unexported methods redeclaration block
+// Redeclared to make it visible to Kotlin for override purposes, workaround for the following issue:
+// https://youtrack.jetbrains.com/issue/KT-56001/Kotlin-Native-import-Objective-C-category-members-as-class-members-if-the-category-is-located-in-the-same-file
+
+- (void)viewSafeAreaInsetsDidChange;
+
 @end
 
 NS_ASSUME_NONNULL_END

compose/ui/ui-uikit/src/uikitMain/objc/CMPUIKitUtils/CMPUIKitUtils/CMPViewController.m

@@ -95,6 +95,10 @@ - (void)viewWillAppear:(BOOL)animated {
     [self viewControllerDidEnterWindowHierarchy];
 }
 
+- (void)viewSafeAreaInsetsDidChange {
+    [super viewSafeAreaInsetsDidChange];
+}
+
 - (void)transitLifecycleToStarted {
     switch (_lifecycleState) {
         case CMPViewControllerLifecycleStateDestroyed:

compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/uikit/ComposeUIViewControllerConfiguration.uikit.kt

@@ -18,6 +18,8 @@ package androidx.compose.ui.uikit
 
 import androidx.compose.runtime.ExperimentalComposeApi
 import androidx.compose.ui.platform.AccessibilitySyncOptions
+import platform.UIKit.UIStatusBarAnimation
+import platform.UIKit.UIStatusBarStyle
 
 /**
  * Configuration of ComposeUIViewController behavior.
@@ -29,8 +31,8 @@ class ComposeUIViewControllerConfiguration {
     var onFocusBehavior: OnFocusBehavior = OnFocusBehavior.FocusableAboveKeyboard
 
     /**
-     * Reassign this property with an object implementing [ComposeUIViewControllerDelegate] to receive
-     * UIViewController lifetime events.
+     * Reassign this property with an object implementing [ComposeUIViewControllerDelegate] to interact with APIs
+     * that otherwise would require subclassing internal implementation of [UIViewController], which is impossible.
      */
     var delegate: ComposeUIViewControllerDelegate = object : ComposeUIViewControllerDelegate {}
 
@@ -56,10 +58,33 @@ class ComposeUIViewControllerConfiguration {
 }
 
 /**
- * Interface for UIViewController specific lifetime callbacks to allow injecting logic without overriding internal ComposeWindow.
- * All of those callbacks are invoked at the very end of overrided function implementation.
+ * Interface for UIViewController to allow injecting logic which otherwise is impossible due to ComposeUIViewController
+ * implementation being internal.
+ * All of those callbacks are invoked at the very end of overriden function and properties implementation.
+ * Default implementations do nothing and return Unit/null (indicating that UIKit default will be used).
  */
 interface ComposeUIViewControllerDelegate {
+    /**
+     * https://developer.apple.com/documentation/uikit/uiviewcontroller/1621416-preferredstatusbarstyle?language=objc
+     * @return null if UIKit default should be used.
+     */
+    val preferredStatusBarStyle: UIStatusBarStyle?
+        get() = null
+
+    /**
+     * https://developer.apple.com/documentation/uikit/uiviewcontroller/1621434-preferredstatusbarupdateanimatio?language=objc
+     * @return null if UIKit default should be used.
+     */
+    val preferredStatysBarAnimation: UIStatusBarAnimation?
+        get() = null
+
+    /**
+     * https://developer.apple.com/documentation/uikit/uiviewcontroller/1621440-prefersstatusbarhidden?language=objc
+     * @return null if UIKit default should be used.
+     */
+    val prefersStatusBarHidden: Boolean?
+        get() = null
+
     fun viewDidLoad() = Unit
     fun viewWillAppear(animated: Boolean) = Unit
     fun viewDidAppear(animated: Boolean) = Unit

compose/ui/ui/src/uikitMain/kotlin/androidx/compose/ui/window/ComposeContainer.uikit.kt

@@ -52,9 +52,11 @@ import androidx.compose.ui.unit.LayoutDirection
 import androidx.compose.ui.util.fastForEach
 import kotlin.coroutines.CoroutineContext
 import kotlin.math.roundToInt
+import kotlin.native.runtime.GC
+import kotlin.native.runtime.NativeRuntimeApi
+import kotlinx.cinterop.BetaInteropApi
 import kotlinx.cinterop.CValue
 import kotlinx.cinterop.ExportObjCClass
-import kotlinx.cinterop.ObjCAction
 import kotlinx.cinterop.readValue
 import kotlinx.cinterop.useContents
 import kotlinx.coroutines.Dispatchers
@@ -80,6 +82,8 @@ import platform.UIKit.UIContentSizeCategoryExtraSmall
 import platform.UIKit.UIContentSizeCategoryLarge
 import platform.UIKit.UIContentSizeCategoryMedium
 import platform.UIKit.UIContentSizeCategorySmall
+import platform.UIKit.UIStatusBarAnimation
+import platform.UIKit.UIStatusBarStyle
 import platform.UIKit.UITraitCollection
 import platform.UIKit.UIUserInterfaceLayoutDirection
 import platform.UIKit.UIUserInterfaceStyle
@@ -92,6 +96,7 @@ import platform.darwin.dispatch_get_main_queue
 private val coroutineDispatcher = Dispatchers.Main
 
 // TODO: Move to androidx.compose.ui.scene
+@OptIn(BetaInteropApi::class)
 @ExportObjCClass
 internal class ComposeContainer(
     private val configuration: ComposeUIViewControllerConfiguration,
@@ -145,10 +150,21 @@ internal class ComposeContainer(
             }
         }
 
-    @Suppress("unused")
-    @ObjCAction
-    fun viewSafeAreaInsetsDidChange() {
-        // super.viewSafeAreaInsetsDidChange() // TODO: call super after Kotlin 1.8.20
+    override fun preferredStatusBarStyle(): UIStatusBarStyle =
+        configuration.delegate.preferredStatusBarStyle
+            ?: super.preferredStatusBarStyle()
+
+    override fun preferredStatusBarUpdateAnimation(): UIStatusBarAnimation =
+        configuration.delegate.preferredStatysBarAnimation
+            ?: super.preferredStatusBarUpdateAnimation()
+
+    override fun prefersStatusBarHidden(): Boolean =
+        configuration.delegate.prefersStatusBarHidden
+            ?: super.prefersStatusBarHidden()
+
+    override fun viewSafeAreaInsetsDidChange() {
+        super.viewSafeAreaInsetsDidChange()
+
         mediator?.viewSafeAreaInsetsDidChange()
         layers.fastForEach {
             it.viewSafeAreaInsetsDidChange()
@@ -270,11 +286,12 @@ internal class ComposeContainer(
         configuration.delegate.viewWillDisappear(animated)
     }
 
+    @OptIn(NativeRuntimeApi::class)
     override fun viewDidDisappear(animated: Boolean) {
         super.viewDidDisappear(animated)
 
         dispatch_async(dispatch_get_main_queue()) {
-            kotlin.native.internal.GC.collect()
+            GC.collect()
         }
 
         lifecycleOwner.handleViewDidDisappear()
@@ -286,17 +303,21 @@ internal class ComposeContainer(
         dispose()
     }
 
+    @OptIn(NativeRuntimeApi::class)
     override fun didReceiveMemoryWarning() {
         println("didReceiveMemoryWarning")
-        kotlin.native.internal.GC.collect()
+        GC.collect()
         super.didReceiveMemoryWarning()
     }
 
     fun createComposeSceneContext(platformContext: PlatformContext): ComposeSceneContext =
         ComposeSceneContextImpl(platformContext)
 
     @OptIn(ExperimentalComposeApi::class)
-    private fun createSkikoUIView(interopContext: UIKitInteropContext, renderRelegate: SkikoRenderDelegate): RenderingUIView =
+    private fun createSkikoUIView(
+        interopContext: UIKitInteropContext,
+        renderRelegate: SkikoRenderDelegate
+    ): RenderingUIView =
         RenderingUIView(interopContext, renderRelegate).apply {
             opaque = configuration.opaque
         }
@@ -395,6 +416,7 @@ internal class ComposeContainer(
     }
 }
 
+@OptIn(BetaInteropApi::class)
 private fun UIViewController.checkIfInsideSwiftUI(): Boolean {
     var parent = parentViewController