Allow viewportSize to be null when it is unresolved.

CHANGELOG.md

@@ -9,6 +9,7 @@ New:
 
 Changed:
 - `ProtocolFactory` interface is now sealed as arbitrary subtypes were never supported. Only schema-generated subtypes should be used.
+- Change `UiConfiguration.viewportSize` to be nullable. A null `viewportSize` indicates the viewport's size has not been resolved yet.
 
 Fixed:
 - Nothing yet!

redwood-composeui/src/commonMain/kotlin/app/cash/redwood/composeui/RedwoodContent.kt

@@ -50,7 +50,7 @@ public fun RedwoodContent(
   content: @Composable () -> Unit,
 ) {
   // If the provider or content change, reset any assumption about the rendered size.
-  var viewportSize by remember(widgetSystem, content) { mutableStateOf(Size.Zero) }
+  var viewportSize: Size? by remember(widgetSystem, content) { mutableStateOf(null) }
 
   val density = LocalDensity.current
   val uiConfiguration = UiConfiguration(

redwood-runtime/api/redwood-runtime.klib.api

@@ -142,7 +142,7 @@ final class app.cash.redwood.ui/Size { // app.cash.redwood.ui/Size|null[0]
 }
 
 final class app.cash.redwood.ui/UiConfiguration { // app.cash.redwood.ui/UiConfiguration|null[0]
-    constructor <init>(kotlin/Boolean = ..., app.cash.redwood.ui/Margin = ..., app.cash.redwood.ui/Size = ..., kotlin/Double = ..., app.cash.redwood.ui/LayoutDirection = ...) // app.cash.redwood.ui/UiConfiguration.<init>|<init>(kotlin.Boolean;app.cash.redwood.ui.Margin;app.cash.redwood.ui.Size;kotlin.Double;app.cash.redwood.ui.LayoutDirection){}[0]
+    constructor <init>(kotlin/Boolean = ..., app.cash.redwood.ui/Margin = ..., app.cash.redwood.ui/Size? = ..., kotlin/Double = ..., app.cash.redwood.ui/LayoutDirection = ...) // app.cash.redwood.ui/UiConfiguration.<init>|<init>(kotlin.Boolean;app.cash.redwood.ui.Margin;app.cash.redwood.ui.Size?;kotlin.Double;app.cash.redwood.ui.LayoutDirection){}[0]
 
     final val darkMode // app.cash.redwood.ui/UiConfiguration.darkMode|{}darkMode[0]
         final fun <get-darkMode>(): kotlin/Boolean // app.cash.redwood.ui/UiConfiguration.darkMode.<get-darkMode>|<get-darkMode>(){}[0]
@@ -153,7 +153,7 @@ final class app.cash.redwood.ui/UiConfiguration { // app.cash.redwood.ui/UiConfi
     final val safeAreaInsets // app.cash.redwood.ui/UiConfiguration.safeAreaInsets|{}safeAreaInsets[0]
         final fun <get-safeAreaInsets>(): app.cash.redwood.ui/Margin // app.cash.redwood.ui/UiConfiguration.safeAreaInsets.<get-safeAreaInsets>|<get-safeAreaInsets>(){}[0]
     final val viewportSize // app.cash.redwood.ui/UiConfiguration.viewportSize|{}viewportSize[0]
-        final fun <get-viewportSize>(): app.cash.redwood.ui/Size // app.cash.redwood.ui/UiConfiguration.viewportSize.<get-viewportSize>|<get-viewportSize>(){}[0]
+        final fun <get-viewportSize>(): app.cash.redwood.ui/Size? // app.cash.redwood.ui/UiConfiguration.viewportSize.<get-viewportSize>|<get-viewportSize>(){}[0]
 
     final fun equals(kotlin/Any?): kotlin/Boolean // app.cash.redwood.ui/UiConfiguration.equals|equals(kotlin.Any?){}[0]
     final fun hashCode(): kotlin/Int // app.cash.redwood.ui/UiConfiguration.hashCode|hashCode(){}[0]

redwood-runtime/src/commonMain/kotlin/app/cash/redwood/ui/UiConfiguration.kt

@@ -30,8 +30,10 @@ public class UiConfiguration(
    * This does not offer any information on the size of the individual composables which are
    * rendering within the composition, but is the frame into which they will render. The root
    * composable if stretching to fill the viewport will match this size.
+   *
+   * A null viewport size indicates it has not been resolved yet.
    */
-  public val viewportSize: Size = Size.Zero,
+  public val viewportSize: Size? = null,
   /**
    * The density of the display. This can be used to convert [Dp] within other properties back to
    * raw pixels, if needed.

redwood-treehouse-host-composeui/src/commonMain/kotlin/app/cash/redwood/treehouse/composeui/TreehouseContent.kt

@@ -59,7 +59,7 @@ public fun <A : AppService> TreehouseContent(
 ) {
   val onBackPressedDispatcher = platformOnBackPressedDispatcher()
 
-  var viewportSize by remember { mutableStateOf(Size.Zero) }
+  var viewportSize: Size? by remember { mutableStateOf(null) }
   val density = LocalDensity.current
   val uiConfiguration = UiConfiguration(
     darkMode = isSystemInDarkTheme(),