[orx-panel] Rename WatchDiv to WatchListDiv, add WatchPropertyDiv

orx-panel/src/demo/kotlin/DemoWatchDiv01.kt

@@ -113,8 +113,8 @@ fun main() = application {
                     }
                 }
 
-                watchDiv("matrix", watchList = programState.matrix) { row ->
-                    watchDiv("row", watchList = row) { item ->
+                watchListDiv("matrix", watchList = programState.matrix) { row ->
+                    watchListDiv("row", watchList = row) { item ->
                         this.id = "some-row"
                         slider {
                             label = "value"

orx-panel/src/main/kotlin/org/openrndr/panel/elements/WatchListDiv.kt

@@ -5,7 +5,7 @@ import kotlinx.coroutines.yield
 import org.openrndr.draw.Drawer
 import org.openrndr.launch
 
-class WatchDiv<T : Any>(private val watchList: List<T>, private val builder: WatchDiv<T>.(T) -> Unit) : Div(), DisposableElement {
+class WatchListDiv<T : Any>(private val watchList: List<T>, private val builder: WatchListDiv<T>.(T) -> Unit) : Div(), DisposableElement {
     override var disposed: Boolean = false
     private var listState = emptyList<T>()
     private var watchJob: Job? = null
@@ -62,8 +62,8 @@ class WatchDiv<T : Any>(private val watchList: List<T>, private val builder: Wat
     }
 }
 
-fun <T : Any> Element.watchDiv(vararg classes: String, watchList: List<T>, builder: WatchDiv<T>.(T) -> Unit) {
-    val wd = WatchDiv(watchList, builder)
+fun <T : Any> Element.watchListDiv(vararg classes: String, watchList: List<T>, builder: WatchListDiv<T>.(T) -> Unit) {
+    val wd = WatchListDiv(watchList, builder)
     wd.classes.addAll(classes.map { ElementClass(it) })
     this.append(wd)
     wd.regenerate()

orx-panel/src/main/kotlin/org/openrndr/panel/elements/WatchPropertyDiv.kt

@@ -0,0 +1,75 @@
+package org.openrndr.panel.elements
+
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.yield
+import org.openrndr.draw.Drawer
+import org.openrndr.launch
+import org.openrndr.panel.elements.*
+import kotlin.reflect.KMutableProperty0
+
+class WatchPropertyDiv<T : Any>(
+    private val watchProperty: KMutableProperty0<T>,
+    private val builder: WatchPropertyDiv<T>.(T) -> Unit
+) : Div(),
+    DisposableElement {
+    override var disposed: Boolean = false
+    private var propertyState = watchProperty.get()
+    private var watchJob: Job? = null
+
+
+    override fun dispose() {
+        super.dispose()
+        for (child in children) {
+            child.parent = null
+            (child as? DisposableElement)?.dispose()
+        }
+        children.clear()
+    }
+
+    fun regenerate(force: Boolean = false) {
+        var regenerate = force
+        if (watchProperty.get() != propertyState) {
+            regenerate = true
+        }
+
+        if (regenerate) {
+            for (child in children) {
+                child.parent = null
+                (child as? DisposableElement)?.dispose()
+            }
+            propertyState = watchProperty.get()
+            children.clear()
+            builder(propertyState)
+
+            requestRedraw()
+        }
+    }
+
+    fun checkJob() {
+        if (watchJob == null) {
+            watchJob = (root() as? Body)?.controlManager?.program?.launch {
+                while (!disposed) {
+                    regenerate()
+                    yield()
+                }
+            }
+        }
+    }
+
+    override fun draw(drawer: Drawer) {
+        checkJob()
+        super.draw(drawer)
+    }
+}
+
+fun <T : Any> Element.watchPropertyDiv(
+    vararg classes: String,
+    watchProperty: KMutableProperty0<T>,
+    builder: WatchPropertyDiv<T>.(T) -> Unit
+) {
+    val wd = WatchPropertyDiv(watchProperty, builder)
+    wd.classes.addAll(classes.map { ElementClass(it) })
+    this.append(wd)
+    wd.regenerate(true)
+    wd.checkJob()
+}