Fixes #11

- Fix dashboard draggin: introduced sophistaced drag handle
- Fix disappearing of charts when dragged inside a dashboard widget

src/main/frontend/components/apex-chart.ts

@@ -59,6 +59,8 @@ function applyThemeOverlay(options: any): any {
 export class ApexChart extends LitElement {
     private chart?: ApexCharts;
     private lastOptions?: any;
+    private lastOptionsJson?: string;
+    private destroyTimer?: ReturnType<typeof setTimeout>;
 
     private readonly onThemeChange = () => {
         if (!this.chart || !this.lastOptions) return;
@@ -71,7 +73,14 @@ export class ApexChart extends LitElement {
 
     connectedCallback() {
         super.connectedCallback();
+        clearTimeout(this.destroyTimer);
+        this.destroyTimer = undefined;
         window.addEventListener('dialect-theme-change', this.onThemeChange);
+        // Back after a real teardown (Flow detach, cached view): rebuild, since
+        // the server only pushes options on setData(), not on re-attach.
+        if (!this.chart && this.lastOptionsJson) {
+            void this.renderChart(this.lastOptionsJson);
+        }
     }
 
     render() {
@@ -80,6 +89,7 @@ export class ApexChart extends LitElement {
 
     async renderChart(optionsJson: string) {
         await this.updateComplete;
+        this.lastOptionsJson = optionsJson;
         const options = JSON.parse(optionsJson);
 
         options.chart = {
@@ -106,6 +116,15 @@ export class ApexChart extends LitElement {
     disconnectedCallback() {
         super.disconnectedCallback();
         window.removeEventListener('dialect-theme-change', this.onThemeChange);
-        this.chart?.destroy();
+        // gridstack's _sortDom() re-appends item elements after every
+        // move/resize, which disconnects and immediately reconnects this
+        // element within the same task — destroying the chart synchronously
+        // would blank it with nothing to trigger a re-render. Defer past the
+        // current task and bail out if we came back.
+        this.destroyTimer = setTimeout(() => {
+            if (this.isConnected) return;
+            this.chart?.destroy();
+            this.chart = undefined;
+        }, 0);
     }
 }