Fixes iOS PaywallFooter height (#247)

RevenueCat · Oct 18, 2024 · 533f1d1 · 533f1d1
1 parent d15464c
commit 533f1d1
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Showing 2 changed files with 63 additions and 18 deletions.
diff --git a/...nuecatui/src/iosMain/kotlin/com/revenuecat/purchases/kmp/ui/revenuecatui/PaywallFooter.kt b/...nuecatui/src/iosMain/kotlin/com/revenuecat/purchases/kmp/ui/revenuecatui/PaywallFooter.kt
@@ -7,13 +7,9 @@ import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.wrapContentHeight
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.runtime.Composable
-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.draw.clip
 import androidx.compose.ui.unit.dp
@@ -26,19 +22,17 @@ public actual fun PaywallFooter(
     options: PaywallOptions,
     mainContent: @Composable ((PaddingValues) -> Unit)?,
 ) {
-    var height by remember { mutableStateOf(0.dp) }
     val paywallComposable = @Composable {
         UIKitPaywall(
             options = options,
             footer = true,
             modifier = Modifier
                 .fillMaxWidth()
+                .animateContentSize()
+                .wrapContentHeight()
                 .clip(
                     RoundedCornerShape(topStart = DefaultCornerRadius, topEnd = DefaultCornerRadius)
-                )
-                .animateContentSize()
-                .height(height),
-            onHeightChange = { newHeight -> height = newHeight.dp }
+                ),
         )
     }
 

diff --git a/revenuecatui/src/iosMain/kotlin/com/revenuecat/purchases/kmp/ui/revenuecatui/UIKitPaywall.kt b/revenuecatui/src/iosMain/kotlin/com/revenuecat/purchases/kmp/ui/revenuecatui/UIKitPaywall.kt
@@ -1,32 +1,67 @@
 package com.revenuecat.purchases.kmp.ui.revenuecatui
 
 import androidx.compose.runtime.Composable
+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.UIKitViewController
+import androidx.compose.ui.layout.layout
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.viewinterop.UIKitViewController
 import cocoapods.PurchasesHybridCommonUI.RCPaywallFooterViewController
 import cocoapods.PurchasesHybridCommonUI.RCPaywallViewController
 import com.revenuecat.purchases.kmp.mappings.toIosOffering
+import kotlinx.cinterop.memScoped
+import kotlinx.cinterop.pointed
 import objcnames.classes.RCOffering
+import platform.UIKit.UIView
 
 @Composable
 internal fun UIKitPaywall(
     options: PaywallOptions,
     footer: Boolean,
     modifier: Modifier = Modifier,
-    onHeightChange: (Int) -> Unit = { },
 ) {
+    val density = LocalDensity.current
+
+    /**
+     * Our intrinsic content size according to UIKit.
+     */
+    var intrinsicContentSizePx by remember { mutableStateOf(0) }
+
+    // We remember this wrapper so we can keep a reference to RCPaywallViewController, even during
+    // recompositions. RCPaywallViewController itself is not yet instantiated here.
+    val viewControllerWrapper = remember { ViewControllerWrapper(null) }
+
     // Keeping references to avoid them being deallocated.
     val dismissRequestedHandler: (RCPaywallViewController?) -> Unit =
         remember(options.dismissRequest) { { options.dismissRequest() } }
-    val delegate = remember(options.listener, onHeightChange) {
-        IosPaywallDelegate(options.listener, onHeightChange)
+    val delegate = remember(options.listener) {
+        IosPaywallDelegate(options.listener) {
+            // UIKit reports that our height was updated, so we're updating intrinsicContentSizePx
+            // to force a new measurement phase (below).
+            viewControllerWrapper.value?.view
+                ?.getIntrinsicContentSizeOfFirstSubView()
+                ?.also { intrinsicContentSizePx = with(density) { it.dp.roundToPx() } }
+        }
     }
-    // We remember this wrapper so we can keep a reference to RCPaywallViewController, even during
-    // recompositions. RCPaywallViewController itself is not yet instantiated here.
-    val viewControllerWrapper = remember { ViewControllerWrapper(null) }
+
     UIKitViewController(
-        modifier = modifier,
+        modifier = modifier.layout { measurable, constraints ->
+            val placeable = measurable.measure(
+                if (constraints.minHeight == 0 && constraints.maxHeight > 0)
+                // We are being asked to wrap our own content height. We will use the measurement
+                // done by UIKit.
+                    constraints.copy(minHeight = intrinsicContentSizePx)
+                else constraints
+            )
+
+            layout(placeable.width, placeable.height) {
+                placeable.placeRelative(0, 0)
+            }
+        },
         factory = {
             val viewController = if (footer) RCPaywallFooterViewController(
                 offering = options.offering?.toIosOffering() as? RCOffering,
@@ -41,12 +76,28 @@ internal fun UIKitPaywall(
             )
 
             viewController
+                .also {
+                    // The first subview has an actual intrinsic content size. We keep a reference
+                    // so we can use it in our measurement phase (above).
+                    it.view.getIntrinsicContentSizeOfFirstSubView()
+                        ?.also { intrinsicContentSizePx = with(density) { it.dp.roundToPx() } }
+                }
                 .apply { setDelegate(delegate) }
                 .also { viewControllerWrapper.value = it }
         },
     )
 }
 
+private fun UIView.getIntrinsicContentSize(): Int {
+    var size: Int? = null
+    memScoped { size = intrinsicContentSize.ptr.pointed.height.toInt() }
+    return size!!
+}
+
+private fun UIView.getIntrinsicContentSizeOfFirstSubView(): Int? =
+    (subviews.firstOrNull() as? UIView)?.getIntrinsicContentSize()
+
+
 /**
  * Can be [remembered][remember] before the RCPaywallViewController is instantiated, so as to
  * "reserve" a spot in the Compose slot table.