add flowlayout drag demo

doric-demo/src/FlowLayoutDragDemo.ts

@@ -0,0 +1,65 @@
+import { Group, Panel, flowlayout, layoutConfig, text, Color, LayoutSpec, Gravity, flowItem } from "doric";
+import { loge } from "doric/lib/src/util/log";
+import { colors } from "./utils";
+
+@Entry
+class FlowLayoutDragDemo extends Panel {
+    private data = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]
+
+    build(rootView: Group) {
+        function insertAt(array: Array<any>, index: number, ...elements: Array<any>) {
+            array.splice(index, 0, ...elements);
+        }
+
+        const flowView = flowlayout({
+            layoutConfig: layoutConfig().most(),
+            itemCount: this.data.length,
+            columnCount: 3,
+            columnSpace: 10,
+            rowSpace: 10,
+            renderItem: (idx) => {
+                return flowItem(
+                    text({
+                        text: `${this.data[idx]}`,
+                        textColor: Color.WHITE,
+                        textSize: 20,
+                        layoutConfig: layoutConfig().fit().configAlignment(Gravity.Center)
+                    }),
+                    {
+                        backgroundColor: colors[this.data[idx] % colors.length],
+                        height: 50,
+                        layoutConfig: layoutConfig().configWidth(LayoutSpec.MOST),
+                        onClick: async () => {
+                            const ret = await flowView.findCompletelyVisibleItems(context)
+                            loge(ret)
+                        }
+                    }
+                )
+            },
+            onScrollEnd: async () => {
+                const ret = await flowView.findCompletelyVisibleItems(context)
+                loge('completelyVisible Items is:', ret)
+
+                const ret2 = await flowView.findVisibleItems(context)
+                loge('visible Items is:', ret2)
+            },
+            canDrag: true,
+            beforeDragging: (from) => {
+                loge(`beforeDragging from: ${from}`)
+            },
+            onDragging: (from, to) => {
+                loge(`onDragging from: ${from}, to: ${to}`)
+            },
+            onDragged: (from, to) => {
+                loge(`onDragged from: ${from}, to: ${to}`)
+
+                const tmp = this.data[from]
+                this.data.splice(from, 1)
+                insertAt(this.data, to, tmp)
+                loge(this.data)
+                flowView.reload(this.context)
+            }
+        }).in(rootView)
+
+    }
+}