Feat: add graphics widget (#34)

* Feat: add graphics widget

* replace binder with assignment; format as Allman; remove redundant undefined

src/elements/controls/graphics.ts

@@ -0,0 +1,43 @@
+import { BuildOutput } from "@src/windows/buildOutput";
+import { ParentControl } from "@src/windows/parentControl";
+import { WidgetCreator } from "@src/windows/widgets/widgetCreator";
+import { ElementParams } from "../elementParams";
+import { AbsolutePosition } from "../layouts/absolute/absolutePosition";
+import { FlexiblePosition } from "../layouts/flexible/flexiblePosition";
+import { Control } from "./control";
+
+/**
+ * The parameters for configuring the custom graphics drawing widget.
+ */
+export interface GraphicsParams extends ElementParams
+{
+    /**
+     * Use for drawing custom graphics. See {@link GraphicsContext} for more information.
+     * @default undefined
+     */
+    onDraw?: (g: GraphicsContext) => void;
+}
+
+/**
+ * Create a custom widget for drawing.
+ */
+export function graphics(params: GraphicsParams & FlexiblePosition): WidgetCreator<FlexiblePosition>;
+export function graphics(params: GraphicsParams & AbsolutePosition): WidgetCreator<AbsolutePosition>;
+export function graphics<I, P>(params: GraphicsParams & I): WidgetCreator<I, P>
+{
+    return (parent, output) => new GraphicsControls<I, P>(parent, output, params);
+}
+
+/**
+ * A controller class for a graphics drawing widget.
+ */
+export class GraphicsControls<I, P> extends Control<CustomDesc, I, P> implements CustomDesc, GraphicsParams
+{
+    onDraw?: ((g: GraphicsContext) => void);
+
+    constructor(parent: ParentControl<I, P>, output: BuildOutput, params: GraphicsParams & I)
+    {
+        super("custom", parent, output, params);
+        this.onDraw = params.onDraw;
+    }
+}

src/index.ts

@@ -30,6 +30,7 @@ export { dropdown, DropdownParams, DropdownDisableMode } from "./elements/contro
 export { dropdownButton, DropdownButtonParams, DropdownButtonAction } from "./elements/controls/dropdownButton";
 export { dropdownSpinner, DropdownSpinnerParams } from "./elements/controls/dropdownSpinner";
 export { flexible, horizontal, vertical, FlexibleLayoutParams, FlexibleLayoutContainer } from "./elements/layouts/flexible/flexible";
+export { graphics, GraphicsParams } from "./elements/controls/graphics";
 export { groupbox, GroupBoxParams } from "./elements/controls/groupbox";
 export { label, LabelParams } from "./elements/controls/label";
 export { listview, ListViewParams, ListViewColumnParams } from "./elements/controls/listview";