kendo-ui for Angular customizing LegendItemComponent

Question

Good morning, everyone. I need to customize my legend-item in donut chart. As I read in documentation I need to define the LegendItemVisualArgs object and initialize the createVisual() method.

Here I'm showing the way I've done it:

export class CustomLegendItemViewModel implements LegendItemVisualArgs {
options: any;
pointIndex: any;
sender: ChartComponent;
series: any;

createVisual(): Circle {
    const geometry = new GeomCircle([10, 10], 10);

    return new Circle(geometry);
}

After That I create this object in my Angular component:

export class ChartItemComponent implements OnInit, OnDestroy {
  visual: CustomLegendItemViewModel = new CustomLegendItemViewModel();
}

And in HTML code I try to bind my custom legend-item view to my object:

<kendo-chart>
            <kendo-chart-series>
                <kendo-chart-series-item [holeSize]="100"
                        type="donut" [data]="data2" [size]="20"
                        categoryField="kind" field="share">
                </kendo-chart-series-item>
            </kendo-chart-series>
            <kendo-chart-legend [visible]="true">
                <kendo-chart-legend-item [visual]="visual"></kendo-chart-legend-item>
            </kendo-chart-legend>
        </kendo-chart>

And I've faced with error that

Uncaught TypeError: customVisual is not a function
at LegendItem.renderVisual (legend-item.js:112)
at LegendLayout.render (legend-layout.js:33)
at Legend.createItems (legend.js:101)
at new Legend (legend.js:27)
at Chart._getModel (chart.js:463)
at Chart._redraw (chart.js:279)
at Chart._noTransitionsRedraw (chart.js:1284)
at Chart._resize (chart.js:134)
at Chart.resize (chart.js:128)
at ChartComponent.push../node_modules/@progress/kendo-angular-charts/dist/es/chart.component.js.ChartComponent.resize (chart.component.js:389)

Does anyone have any ideas how can I solve it? Or just send some reference to customizing example.

Thanks!

Answer 1

Based on the API you need to provide a function to the visual input. (API Reference)

In the code below I am binding the function visualFn to the input visual. (Working example)

html

<kendo-chart>
    ...
    <kendo-chart-legend [visible]="true">
        <kendo-chart-legend-item [visual]="visualFn"></kendo-chart-legend-item>
    </kendo-chart-legend>
</kendo-chart>

component

public visualFn(e: SeriesVisualArgs): Group {
    const geometry = new GeomCircle([10, 10], 10);
    return new Circle(geometry);
}