feat(chart): add no data template documentation (#673)

Author: P1l3T0

controls/htmlchart/functionality/no-data-template.md

@@ -0,0 +1,114 @@
+---
+title: No Data Template
+page_title: No Data Template - RadHtmlChart
+description: Learn how to use the No Data Template of the RadHtmlChart.
+slug: htmlchart/functionality/no-data-template
+tags: no data, template, no data template, htmlchart, chart, telerik, kendo
+published: True
+position: 7
+---
+
+# No Data Template
+
+The Telerik WebForms Chart component allows to display a message when there is no data to show. This feature is particularly useful when loading data asynchronously, as it reassures users that data may appear after a delay. 
+
+Customizing the No Data Template is simple, enabling to add styling or interactive elements like buttons to improve usability. The No Data Template can be used for all [chart types]({% slug htmlchart/chart-types/overview %}). Here's how to set up a custom message for scenarios where the chart data is unavailable.
+
+
+## Example with Bar Chart
+
+````ASP.NET
+<telerik:RadHtmlChart runat="server" ID="RadHtmlChart1" Width="1000px">
+    <NoDataTemplate>
+        <button onclick="onClick(); return false;">Refetch</button>
+    </NoDataTemplate>
+    <PlotArea>
+        <Series>
+            <telerik:ColumnSeries DataFieldY="nuclear" Name="Nuclear" />
+            <telerik:ColumnSeries DataFieldY="hydro" Name="Hydro" />
+            <telerik:ColumnSeries DataFieldY="wind" Name="Wind" />
+        </Series>
+    </PlotArea>
+</telerik:RadHtmlChart>
+````
+
+````JavaScript
+function onClick() {
+    let chart = $find("<%= RadHtmlChart1.ClientID %>").get_kendoWidget();
+    let dataSource = [{
+            "country": "Spain",
+            "year": "2024",
+            "unit": "GWh",
+            "solar": 2578,
+            "hydro": 26112,
+            "wind": 32203,
+            "nuclear": 58973
+        }, {
+            "country": "Spain",
+            "year": "2023",
+            "unit": "GWh",
+            "solar": 508,
+            "hydro": 30522,
+            "wind": 27568,
+            "nuclear": 55103
+        }, {
+            "country": "Spain",
+            "year": "2022",
+            "unit": "GWh",
+            "solar": 119,
+            "hydro": 29831,
+            "wind": 23297,
+            "nuclear": 60126
+        }, {
+            "country": "Spain",
+            "year": "2021",
+            "unit": "GWh",
+            "solar": 41,
+            "hydro": 23025,
+            "wind": 21176,
+            "nuclear": 57539
+        }, {
+            "country": "Spain",
+            "year": "2020",
+            "unit": "GWh",
+            "solar": 56,
+            "hydro": 34439,
+            "wind": 15700,
+            "nuclear": 63606
+        }, {
+            "country": "Spain",
+            "year": "2019",
+            "unit": "GWh",
+            "solar": 41,
+            "hydro": 43897,
+            "wind": 12075,
+            "nuclear": 61875
+        }, {
+            "country": "Spain",
+            "year": "2018",
+            "unit": "GWh",
+            "solar": 30,
+            "hydro": 26270,
+            "wind": 9342,
+            "nuclear": 63016
+        }, {
+            "country": "Spain",
+            "year": "2017",
+            "unit": "GWh",
+            "solar": 24,
+            "hydro": 43864,
+            "wind": 6759,
+            "nuclear": 63708
+        }, {
+            "country": "Spain",
+            "year": "2016",
+            "unit": "GWh",
+            "solar": 18,
+            "hydro": 31807,
+            "wind": 4727,
+            "nuclear": 62206
+        }];
+
+    chart.setDataSource(dataSource);
+}
+````