feat(tooltip): add target attribute

src/components/popover/bl-popover.ts

@@ -13,6 +13,7 @@ import {
   Middleware,
   MiddlewareState,
 } from "@floating-ui/dom";
+import { getTarget } from "../../utilities/elements";
 import { event, EventDispatcher } from "../../utilities/event";
 import style from "./bl-popover.css";
 
@@ -176,15 +177,16 @@ export default class BlPopover extends LitElement {
   }
 
   set target(value: string | Element) {
-    if (typeof value === "string") {
-      this._target = document.getElementById(value) as Element;
-    } else if (value instanceof Element) {
-      this._target = value;
-    } else {
+    const target = getTarget(value);
+
+    if (!target) {
       console.warn(
         "BlPopover target only accepts an Element instance or a string id of a DOM element."
       );
+      return;
     }
+
+    this._target = target;
   }
 
   /**

src/components/tooltip/bl-tooltip.stories.mdx

@@ -44,6 +44,13 @@ export const PlacementTemplate = (args) => html`
   You can use this section to cancel your order.
 </bl-tooltip>`
 
+export const TargetAttrTemplate = (args) => html`
+<bl-tooltip placement="${ifDefined(args.placement)}" target="trigger-btn">
+  Target Attribute
+</bl-tooltip>
+<bl-button id="trigger-btn">With Target</bl-button>
+`;
+
 # Tooltip
 
 <bl-badge icon="document">ADR</bl-badge>
@@ -153,6 +160,14 @@ For example, if there is not enough room on the top, the tooltip is shown on the
   </Story>
 </Canvas>
 
+## Target Attribute
+
+By using the target attribute, we can add a tooltip to the element.
+
+<Canvas>
+  <Story name="Usage With Target Attribute" play={tooltipOpener}>{TargetAttrTemplate.bind({})}</Story>
+</Canvas>
+
 ## Reference
 
 <ArgsTable of="bl-tooltip" />

src/components/tooltip/bl-tooltip.test.ts

@@ -202,4 +202,54 @@ describe("bl-tooltip", () => {
     expect(ev).to.exist;
     expect(el.visible).to.be.false;
   });
+
+  it("should work with target attribute", async () => {
+    // given
+    const el = await fixture(html`
+      <div><bl-tooltip target="btn">Tooltip Text</bl-tooltip><button type="button" id="btn">Test</button></div>`);
+
+    const tooltipEl = el.querySelector("bl-tooltip")!;
+    const trigger = el.querySelector<HTMLButtonElement>("#btn")!;
+
+    // when
+    const { x, y } = getMiddleOfElement(trigger);
+
+    setTimeout(() => sendMouse({ type: "move", position: [x, y] }));
+
+    // then
+    const ev = await oneEvent(tooltipEl, "bl-tooltip-show");
+
+    expect(ev).to.exist;
+    expect(ev.detail).to.be.equal("");
+  });
+
+  it("should remove previous target elements", async () => {
+    // given
+    const el = await fixture(html`
+      <div><bl-tooltip target="btn">Tooltip Text</bl-tooltip><button type="button" id="btn">Test</button><button type="button" id="new-btn">Test</button></div>`);
+
+    const tooltipEl = el.querySelector("bl-tooltip")!;
+    const triggerPrev = el.querySelector<HTMLButtonElement>("#btn")!;
+
+    // when
+    tooltipEl.target = "new-btn";
+    const { x, y } = getMiddleOfElement(triggerPrev);
+
+    setTimeout(() => sendMouse({ type: "move", position: [x, y] }));
+
+    // then
+    const ev = await new Promise(resolve => {
+      function listener(ev: Event) {
+        resolve(ev);
+        tooltipEl.removeEventListener("bl-tooltip-show", listener);
+      }
+      tooltipEl.addEventListener("bl-tooltip-show", listener);
+      setTimeout(() => {
+        resolve(null);
+        tooltipEl.removeEventListener("bl-tooltip-show", listener);
+      }, 200);
+    });
+
+    expect(ev).to.be.eq(null);
+  });
 });

src/components/tooltip/bl-tooltip.ts

@@ -1,7 +1,8 @@
-import { CSSResultGroup, html, LitElement, TemplateResult } from "lit";
+import { CSSResultGroup, html, LitElement, PropertyValues, TemplateResult } from "lit";
 import { customElement, property, query } from "lit/decorators.js";
 import { ifDefined } from "lit/directives/if-defined.js";
 import { ReferenceElement } from "@floating-ui/core";
+import { getTarget } from "../../utilities/elements";
 import { event, EventDispatcher } from "../../utilities/event";
 import "../popover/bl-popover";
 import BlPopover, { Placement } from "../popover/bl-popover";
@@ -39,11 +40,64 @@ export default class BlTooltip extends LitElement {
    */
   @event("bl-tooltip-hide") private onHide: EventDispatcher<string>;
 
+  @property() target: string | Element;
+
+  protected update(changedProperties: PropertyValues) {
+    if (changedProperties.has("target")) {
+      const prev = changedProperties.get("target");
+
+      if (prev) {
+        this._removeEvents(prev);
+      }
+
+      this._addEvents();
+    }
+
+    super.update(changedProperties);
+  }
+
+  private _addEvents() {
+    const target = getTarget(this.target);
+
+    if (target) {
+      target.addEventListener("focus", this.show, { capture: true });
+      target.addEventListener("mouseover", this.show);
+      target.addEventListener("blur", this.hide, { capture: true });
+      target.addEventListener("mouseleave", this.hide);
+    }
+  }
+
+  private _removeEvents(value: string | Element) {
+    const target = getTarget(value);
+
+    if (target) {
+      target.removeEventListener("focus", this.show, { capture: true });
+      target.removeEventListener("mouseover", this.show);
+      target.removeEventListener("blur", this.hide, { capture: true });
+      target.removeEventListener("mouseleave", this.hide);
+    }
+  }
+
+  connectedCallback() {
+    super.connectedCallback();
+
+    this.show = this.show.bind(this);
+    this.hide = this.hide.bind(this);
+
+    this._addEvents();
+  }
+
+  disconnectedCallback() {
+    super.disconnectedCallback();
+
+    this._removeEvents(this.target);
+  }
+
   /**
    * Shows tooltip
    */
   show() {
-    this._popover.target = this.trigger;
+    this._popover.target = this.target ?? this.trigger;
     this._popover.show();
     this.onShow("");
   }
@@ -78,9 +132,9 @@ export default class BlTooltip extends LitElement {
 
   render(): TemplateResult {
     return html`
-      ${this.triggerTemplate()}
+      ${this.target ? "" : this.triggerTemplate()}
       <bl-popover
-        .target="${this.trigger}"
+        .target="${this.target ?? this.trigger}"
         placement="${ifDefined(this.placement)}"
         @bl-popover-hide="${() => this.onHide("")}"
       >

src/utilities/elements.ts

@@ -6,3 +6,13 @@ export function getMiddleOfElement(element: Element) {
     y: Math.floor(y + window.pageYOffset + height / 2),
   };
 }
+
+export function getTarget(value: string | Element): Element | null {
+  if (typeof value === "string") {
+    return document.getElementById(value) as Element;
+  } else if (value instanceof Element) {
+    return value;
+  }
+
+  return null;
+}