Added new kb article htmlchart-keyboard-accessibility-for-series-items (#664)

Co-authored-by: KB Bot <[email protected]>

Author: github-actions[bot]

knowledge-base/htmlchart-keyboard-accessibility-for-series-items.md

@@ -0,0 +1,73 @@
+---
+title: Enabling Keyboard Accessibility for RadHtmlChart Series
+description: Learn how to make RadHtmlChart series focusable and clickable via the Enter key for keyboard navigation and accessibility.
+type: how-to
+page_title: Making RadHtmlChart Bar Series Accessible with Keyboard
+slug: htmlchart-keyboard-accessibility-for-series-items
+tags: radhtmlchart, accessibility, keyboard, focus, click, asp.net ajax
+res_type: kb
+ticketid: 1680317
+---
+
+## Description
+
+In web development, ensuring accessibility for all users, including those relying on keyboard navigation, is crucial. This knowledge base article provides a guide on making the series in a RadHtmlChart focusable and clickable via the Enter key. This functionality is essential for implementing drill-down features accessible through keyboard navigation, in line with WCAG 2.1 guidelines.
+
+This knowledge base article also answers the following questions:
+- How can I make the RadHtmlChart series focusable using keyboard navigation?
+- How do I enable clicking on RadHtmlChart series with the Enter key for drill-down functionality?
+- What are the steps to achieve keyboard accessibility for RadHtmlChart in ASP.NET AJAX applications?
+
+## Solution
+
+To enable keyboard navigation and accessibility for the RadHtmlChart series, follow these steps:
+
+1. Ensure each bar in the RadHtmlChart is focusable by setting its `tabindex` to `"0"`.
+2. Add a keydown event listener to each focusable bar.
+3. In the event listener, check if the Enter key is pressed. If so, manually trigger the desired click action.
+
+### Updated JavaScript Code
+
+````JavaScript
+function onChartLoad(sender, args) {
+    setTimeout(function () {
+        var chart = $find("<%= AssetRadChart.ClientID %>");
+        if (chart) {
+            var kendoChart = chart.get_kendoWidget ? chart.get_kendoWidget() : null;
+            if (kendoChart) {
+                var bars = kendoChart.element.find("svg path[fill]:not([fill='none'])");
+                if (bars.length > 0) {
+                    bars.attr("tabindex", "0"); // Make bars focusable
+                    bars.first().focus();
+
+                    // Add keydown event listener to make bars clickable via Enter key
+                    bars.on('keydown', function (e) {
+                        if (e.key === 'Enter') {
+                            var seriesIndex = $(this).index();
+                            var dataItem = kendoChart.dataSource.view()[seriesIndex];
+                            var sender = {
+                                series: { field: kendoChart.options.series[seriesIndex].field },
+                                dataItem: dataItem
+                            };
+                            OnClientSeriesClicked(sender);
+                        }
+                    });
+                }
+            }
+        }
+    }, 1000);
+}
+````
+
+### Explanation
+
+- **Tabindex:** By setting `tabindex="0"`, the SVG path elements become focusable, allowing for navigation through chart bars using the Tab key.
+- **Keydown Event:** The keydown event listener on each bar checks for the Enter key press (`e.key === 'Enter'`).
+- **Simulate Click:** Upon detecting the Enter key press, the code constructs a `sender` object, mimicking the one during a mouse click, and invokes the `OnClientSeriesClicked` function.
+
+Implementing this solution will make the RadHtmlChart series not only focusable but also clickable via the Enter key, enhancing accessibility in compliance with WCAG 2.1 guidelines.
+
+## See Also
+
+- [RadHtmlChart Documentation](https://docs.telerik.com/devtools/aspnet-ajax/controls/htmlchart/overview)
+- [Keyboard Accessibility in Web Applications](https://www.w3.org/WAI/standards-guidelines/wcag/)