Merge pull request #51 from huanshankeji/box-with-constraints-react-to-size-changes-js-dom

Fix JS DOM display issues in `BoxWithConstraints` and `com.huanshankeji.compose.material2.ext.TopAppBarScaffold`

Author: ShreckYe

common/src/commonMain/kotlin/com/huanshankeji/compose/foundation/Scroll.kt

@@ -2,6 +2,7 @@ package com.huanshankeji.compose.foundation
 
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.Stable
+import com.huanshankeji.compose.ExperimentalApi
 import com.huanshankeji.compose.foundation.layout.BoxScope
 import com.huanshankeji.compose.ui.Alignment
 import com.huanshankeji.compose.ui.Modifier
@@ -24,6 +25,7 @@ See https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollTop.
  * it applies to the target as a whole on `androidx` targets, but applies to its content on JS DOM.
  * For consistency on different platforms, [VerticalScrollBox] is recommended over this modifier.
  */
+@ExperimentalApi
 expect fun Modifier.verticalScroll(
     state: ScrollState
     /*
@@ -37,6 +39,7 @@ expect fun Modifier.verticalScroll(
  * For consistency on different platforms, [HorizontalScrollBox] is recommended over this modifier.
  * @see verticalScroll
  */
+@ExperimentalApi
 expect fun Modifier.horizontalScroll(state: ScrollState): Modifier
 
 @Composable

common/src/commonMain/kotlin/com/huanshankeji/compose/ui/unit/ext/DpOrPercentage.kt

@@ -1,8 +1,10 @@
 package com.huanshankeji.compose.ui.unit.ext
 
 import androidx.annotation.IntRange
+import com.huanshankeji.compose.ExperimentalApi
 
 // not used yet
+@ExperimentalApi
 sealed class DpOrPercentage {
     class Dp(val dp: androidx.compose.ui.unit.Dp) : DpOrPercentage()
     class Percentage(@IntRange(0, 100) val percentage: Int) : DpOrPercentage()

common/src/jsMain/kotlin/com/huanshankeji/compose/foundation/Scroll.js.kt

@@ -34,7 +34,6 @@ actual object ScrollState
 actual fun Modifier.verticalScroll(state: ScrollState): Modifier =
     platformModify { verticalScroll() }
 
-
 actual fun Modifier.horizontalScroll(state: ScrollState): Modifier =
     platformModify { horizontalScroll() }
 

common/src/jsMain/kotlin/com/huanshankeji/compose/foundation/layout/ext/BoxWithConstraints.js.kt

@@ -7,6 +7,7 @@ import com.huanshankeji.compose.foundation.ExperimentalFoundationApi
 import com.huanshankeji.compose.foundation.layout.Box
 import com.huanshankeji.compose.ui.Alignment
 import com.huanshankeji.compose.ui.Modifier
+import com.varabyte.kobweb.browser.dom.observers.ResizeObserver
 import com.varabyte.kobweb.compose.foundation.layout.BoxScope
 import com.varabyte.kobweb.compose.ui.attrsModifier
 
@@ -17,16 +18,41 @@ actual fun BoxWithConstraints(
     contentAlignment: Alignment,
     content: @Composable BoxWithConstraintsScope.() -> Unit
 ) {
+    // `DpClientSize.unspecified` instead of null can be used by default to prevent the content from not rendering when `clientSize` is not set
     var clientSize by remember { mutableStateOf<ClientSize?>(null) }
+    // `DivBox` doesn't work here either, so it should not be Kobweb's problem.
     Box(
-        Modifier.platformModify {
-            attrsModifier {
-                ref {
-                    clientSize = ClientSize(it.clientWidth, it.clientHeight)
-                    onDispose { clientSize = null }
+        Modifier.fillMaxSizeStretch()
+            .platformModify {
+                attrsModifier {
+                    ref {
+                        //console.log("Initial client size: ${it.clientWidth}, ${it.clientHeight}")
+                        //clientSize = ClientSize(it.clientWidth, it.clientHeight)
+                        val resizeObserver = ResizeObserver { entries, _ ->
+                            val element = entries.single().target
+
+                            /*
+                            console.log("width: ${element.clientWidth}, height: ${element.clientHeight}")
+                            console.log(entries.first().contentBoxSize.first())
+                            console.log(entries.first().borderBoxSize.first())
+                            console.log(entries.first().devicePixelContentBoxSize.first()) // If there is zoom this one is different from the 2 above.
+                            */
+
+                            with(element) {
+                                //console.log("width: $clientWidth, height: $clientHeight")
+                                clientSize = ClientSize(clientWidth, clientHeight)
+                            }
+                        }
+                        resizeObserver.observe(it)
+
+                        onDispose {
+                            //resizeObserver.unobserve(it)
+                            resizeObserver.disconnect()
+                            clientSize = null
+                        }
+                    }
                 }
             }
-        }.fillMaxSizeStretch()
             .then(modifier),
         contentAlignment
     ) {
@@ -45,3 +71,13 @@ class BoxWithConstraintsScopeImpl(
 ) : BoxWithConstraintsScope
 
 private class ClientSize(val clientWidth: Int, val clientHeight: Int)
+
+// removed if not used
+/**
+ * Made in [Dp] so [Dp.Unspecified] can be used.
+ */
+private class DpClientSize(val clientWidth: Dp, val clientHeight: Dp) {
+    companion object {
+        val unspecified = DpClientSize(Dp.Unspecified, Dp.Unspecified)
+    }
+}

material2/src/jsMain/kotlin/com/huanshankeji/compose/material2/ext/TopAppBarScaffold.js.kt

@@ -121,6 +121,8 @@ actual fun TopAppBarScaffold(
             actions,
             Modifier.weight(1f).fillMaxWidthStretch()
         ) {
+            // This part has a lot of nested `Div`s but works. Do not change unless you are sure that expected behavior is not broken.
+
             // The content gets hidden behind the top app bar if this div is not added.
             Div({
                 style {
@@ -134,9 +136,16 @@ actual fun TopAppBarScaffold(
                         //overflow(Overflow.Auto) // This seems not needed. TODO remove if confirmed to be not needed
                     }
                 }) {
-                    // see `ScaffoldLayoutWithMeasureFix`
-                    val innerPadding = PaddingValues()
-                    content(innerPadding)
+                    // This nested `Div` is here so that a child using `fillMaxSizeStretch` works properly. `fillMaxSizeStretch` seems buggy when used directly in the `position: absolute` parent.
+                    Div({
+                        style {
+                            height(100.percent)
+                        }
+                    }) {
+                        // see `ScaffoldLayoutWithMeasureFix`
+                        val innerPadding = PaddingValues()
+                        content(innerPadding)
+                    }
                 }
 
                 floatingActionButton?.let { fabWithPosition(it) }

material3/src/jsMain/kotlin/com/huanshankeji/compose/material3/lazy/ext/List.js.kt

@@ -90,6 +90,12 @@ actual class ListScope(val mdListScope: MdListScope) {
 
 actual class ItemScope(val mdListItemScope: MdListItemScope)
 
+/*
+@Composable
+fun PrimitiveList() =
+    TODO() as Unit
+*/
+
 @Composable
 actual fun List(
     modifier: Modifier,