Add BoxScope for Box

Author: ShreckYe

compose-multiplatform-common/src/commonMain/kotlin/com/huanshankeji/compose/layout/Layouts.kt

@@ -6,5 +6,7 @@ import com.huanshankeji.compose.ui.ModifierOrAttrs
 
 expect abstract class BoxElement : Element
 
+expect interface BoxScope
+
 @Composable
-expect fun Box(modifierOrAttrs: ModifierOrAttrs<BoxElement> = null, content: @Composable () -> Unit)
+expect fun Box(modifierOrAttrs: ModifierOrAttrs<BoxElement> = null, content: @Composable BoxScope.() -> Unit)

compose-multiplatform-common/src/jsMain/kotlin/com/huanshankeji/compose/layout/Layouts.kt

@@ -4,10 +4,18 @@ import androidx.compose.runtime.Composable
 import com.huanshankeji.compose.ui.ModifierOrAttrs
 import com.huanshankeji.compose.ui.toAttrs
 import org.jetbrains.compose.web.dom.Div
+import org.jetbrains.compose.web.dom.ElementScope
 import org.w3c.dom.HTMLDivElement
 
 actual typealias BoxElement = HTMLDivElement
 
+//actual typealias BoxScope = ElementScope<HTMLDivElement>
+actual interface BoxScope {
+    val htmlDivElementScope: ElementScope<HTMLDivElement>
+
+    class Impl(override val htmlDivElementScope: ElementScope<HTMLDivElement>) : BoxScope
+}
+
 @Composable
-actual fun Box(modifierOrAttrs: ModifierOrAttrs<BoxElement>, content: @Composable () -> Unit) =
-    Div(modifierOrAttrs.toAttrs()) { content() }
+actual fun Box(modifierOrAttrs: ModifierOrAttrs<BoxElement>, content: @Composable BoxScope.() -> Unit) =
+    Div(modifierOrAttrs.toAttrs()) { BoxScope.Impl(this).content() }

compose-multiplatform-common/src/jvmMain/kotlin/com/huanshankeji/compose/layout/Layouts.kt

@@ -7,6 +7,8 @@ import com.huanshankeji.compose.ui.toModifier
 
 actual abstract class BoxElement : Element()
 
+actual typealias BoxScope = androidx.compose.foundation.layout.BoxScope
+
 @Composable
-actual fun Box(modifierOrAttrs: ModifierOrAttrs<BoxElement>, content: @Composable () -> Unit) =
-    androidx.compose.foundation.layout.Box(modifierOrAttrs.toModifier()) { content() }
+actual fun Box(modifierOrAttrs: ModifierOrAttrs<BoxElement>, content: @Composable BoxScope.() -> Unit) =
+    androidx.compose.foundation.layout.Box(modifierOrAttrs.toModifier(), content = content)