add Gopt_Game_Gopx_GetWidget in widget for ispx runtime

widget/widget.go

@@ -0,0 +1,20 @@
+package widget
+
+import (
+	"github.com/goplus/spx"
+)
+
+func Gopt_Game_Gopx_GetWidget[T any](sg spx.ShapeGetter, name string) *T {
+	items := sg.GetAllShapes()
+	for _, item := range items {
+		widget, ok := item.(spx.Widget)
+		if ok && widget.GetName() == name {
+			if result, ok := widget.(interface{}).(*T); ok {
+				return result
+			} else {
+				panic("GetWidget: type mismatch")
+			}
+		}
+	}
+	panic("GetWidget: widget not found - " + name)
+}