fix(radio-button-group): no longer focus first radio button on label click and adds setFocus method. (#7050)

**Related Issue:**  #6698

## Summary

This PR will remove the focus flash from the first
`calcite-radio-button` in group on label click

Additional enhancements:
- Adds `setFocus( )` method in `calcite-radio-button-group`
- Users will be able to select label text in chrome. #6357 

Note:
With this PR, `delegateFocus` is removed from
`calcite-radio-button-group` which is causing #6698. Because the
tabIndex is set to 0 for the first focusable element on page load to
enable keyboard navigation into the group it makes `delegateFocus` to
apply focus styles on the first focusable element when the user clicks
on the label (invokes .focus( )) resulting in the behavior mentioned in
the issue 6698. To resolve this, `delegateFocus` is removed and added
`setFocus( )` method.

Author: anveshmekala

packages/calcite-components/src/components/radio-button-group/radio-button-group.e2e.ts

@@ -1,6 +1,7 @@
 import { newE2EPage } from "@stencil/core/testing";
-import { accessible, defaults, hidden, reflects, renders } from "../../tests/commonTests";
+import { accessible, defaults, focusable, hidden, reflects, renders } from "../../tests/commonTests";
 import { html } from "../../../support/formatting";
+import { getFocusedElementProp } from "../../tests/utils";
 
 describe("calcite-radio-button-group", () => {
   describe("renders", () => {
@@ -20,6 +21,22 @@ describe("calcite-radio-button-group", () => {
     ]);
   });
 
+  describe("is focusable", () => {
+    focusable(
+      html`<calcite-radio-button-group name="Options" layout="vertical">
+        <calcite-label layout="inline">
+          <calcite-radio-button value="flowers" disabled></calcite-radio-button>
+          Flowers
+        </calcite-label>
+        <calcite-label layout="inline">
+          <calcite-radio-button value="trees"></calcite-radio-button>
+          Trees
+        </calcite-label>
+      </calcite-radio-button-group>`,
+      { focusTargetSelector: "calcite-radio-button" }
+    );
+  });
+
   describe("honors hidden attribute", () => {
     hidden("calcite-radio-button");
 
@@ -452,4 +469,52 @@ describe("calcite-radio-button-group", () => {
     expect(changeEvent).toHaveReceivedEventTimes(3);
     expect(await getSelectedItemValue()).toBe("three");
   });
+
+  it("should focus the checked radio-button on setFocus()", async () => {
+    const page = await newE2EPage();
+    await page.setContent(html`
+      <calcite-radio-button-group name="Options" layout="vertical">
+        <calcite-label layout="inline">
+          <calcite-radio-button value="trees" disabled id="trees"></calcite-radio-button>
+          Trees
+        </calcite-label>
+        <calcite-label layout="inline">
+          <calcite-radio-button value="shrubs" id="shrubs"></calcite-radio-button>
+          Shrubs
+        </calcite-label>
+        <calcite-label layout="inline">
+          <calcite-radio-button value="flowers" id="flowers" checked></calcite-radio-button>
+          Flowers
+        </calcite-label>
+      </calcite-radio-button-group>
+    `);
+    const group = await page.find("calcite-radio-button-group");
+    await group.callMethod("setFocus");
+    await page.waitForChanges();
+    expect(await getFocusedElementProp(page, "id")).toBe("flowers");
+  });
+
+  it("should focus the first focusable radio-button on setFocus()", async () => {
+    const page = await newE2EPage();
+    await page.setContent(html`
+      <calcite-radio-button-group name="Options" layout="vertical">
+        <calcite-label layout="inline">
+          <calcite-radio-button value="trees" disabled id="trees"></calcite-radio-button>
+          Trees
+        </calcite-label>
+        <calcite-label layout="inline">
+          <calcite-radio-button value="shrubs" id="shrubs"></calcite-radio-button>
+          Shrubs
+        </calcite-label>
+        <calcite-label layout="inline">
+          <calcite-radio-button value="flowers" id="flowers"></calcite-radio-button>
+          Flowers
+        </calcite-label>
+      </calcite-radio-button-group>
+    `);
+    const group = await page.find("calcite-radio-button-group");
+    await group.callMethod("setFocus");
+    await page.waitForChanges();
+    expect(await getFocusedElementProp(page, "id")).toBe("shrubs");
+  });
 });

packages/calcite-components/src/components/radio-button-group/radio-button-group.tsx

@@ -6,24 +6,30 @@ import {
   h,
   Host,
   Listen,
+  Method,
   Prop,
+  State,
   VNode,
   Watch
 } from "@stencil/core";
 import { createObserver } from "../../utils/observers";
 import { Layout, Scale } from "../interfaces";
+import {
+  componentLoaded,
+  LoadableComponent,
+  setComponentLoaded,
+  setUpLoadableComponent
+} from "../../utils/loadable";
 
 /**
  * @slot - A slot for adding `calcite-radio-button`s.
  */
 @Component({
   tag: "calcite-radio-button-group",
   styleUrl: "radio-button-group.scss",
-  shadow: {
-    delegatesFocus: true
-  }
+  shadow: true
 })
-export class RadioButtonGroup {
+export class RadioButtonGroup implements LoadableComponent {
   //--------------------------------------------------------------------------
   //
   //  Element
@@ -91,6 +97,8 @@ export class RadioButtonGroup {
 
   mutationObserver = createObserver("mutation", () => this.passPropsToRadioButtons());
 
+  @State() radioButtons: HTMLCalciteRadioButtonElement[] = [];
+
   //--------------------------------------------------------------------------
   //
   //  Lifecycle
@@ -102,6 +110,14 @@ export class RadioButtonGroup {
     this.mutationObserver?.observe(this.el, { childList: true, subtree: true });
   }
 
+  componentWillLoad(): void {
+    setUpLoadableComponent(this);
+  }
+
+  componentDidLoad(): void {
+    setComponentLoaded(this);
+  }
+
   disconnectedCallback(): void {
     this.mutationObserver?.disconnect();
   }
@@ -113,10 +129,11 @@ export class RadioButtonGroup {
   //--------------------------------------------------------------------------
 
   private passPropsToRadioButtons = (): void => {
-    const radioButtons = this.el.querySelectorAll("calcite-radio-button");
-    this.selectedItem = Array.from(radioButtons).find((radioButton) => radioButton.checked) || null;
-    if (radioButtons.length > 0) {
-      radioButtons.forEach((radioButton) => {
+    this.radioButtons = Array.from(this.el.querySelectorAll("calcite-radio-button"));
+    this.selectedItem =
+      Array.from(this.radioButtons).find((radioButton) => radioButton.checked) || null;
+    if (this.radioButtons.length > 0) {
+      this.radioButtons.forEach((radioButton) => {
         radioButton.disabled = this.disabled || radioButton.disabled;
         radioButton.hidden = this.hidden;
         radioButton.name = this.name;
@@ -126,6 +143,10 @@ export class RadioButtonGroup {
     }
   };
 
+  private getFocusableRadioButton(): HTMLCalciteRadioButtonElement | null {
+    return this.radioButtons.find((radiobutton) => !radiobutton.disabled) ?? null;
+  }
+
   //--------------------------------------------------------------------------
   //
   //  Events
@@ -137,6 +158,25 @@ export class RadioButtonGroup {
    */
   @Event({ cancelable: false }) calciteRadioButtonGroupChange: EventEmitter<void>;
 
+  //--------------------------------------------------------------------------
+  //
+  //  Public Method
+  //
+  //--------------------------------------------------------------------------
+
+  /** Sets focus on the fist focusable `calcite-radio-button` element in the component. */
+  @Method()
+  async setFocus(): Promise<void> {
+    await componentLoaded(this);
+    if (this.selectedItem && !this.selectedItem.disabled) {
+      this.selectedItem.setFocus();
+      return;
+    }
+    if (this.radioButtons.length > 0) {
+      this.getFocusableRadioButton()?.setFocus();
+    }
+  }
+
   //--------------------------------------------------------------------------
   //
   //  Event Listeners