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<text-editable>click to edit</text-editable>
class TextEditable extends HTMLElement {
// Your element is being constructed. It is not connected to the page yet!
// It will also be called when you use `document.createElement`
constructor() {
// you must call super(). The browser will remind you if you don't ;-)
super();
// We prepare the shadow dom so that all the inner elements are private
// and don't interfere with the page
this.shadow = this.attachShadow({ mode: "open" });
}
connectedCallback() {
// populate our shadow dom with our style and html
this.shadow.innerHTML = `
<style>${this.getStyle()}</style>
${this.getHtml()}
`;
// keep a reference of the main elements in the html
this.span = this.shadow.querySelector("span");
this.input = this.shadow.querySelector("input");
this.div = this.shadow.querySelector("div");
// Add listeners to the different elements
this.span.addEventListener(
"click",
(this.onTextClickedListener = this.onTextClicked.bind(this))
);
this.input.addEventListener(
"blur",
(this.onInputBlurListener = this.onInputBlur.bind(this))
);
this.input.addEventListener(
"keyup",
(this.onKeyPressListener = this.onKeyPress.bind(this))
);
}
onTextClicked() {
// copy the text to the input element
this.input.value = this.textContent;
// show the input field
this.switchMode("edit");
}
onInputBlur() {
// just restore the normal text without changing it
this.switchMode("normal");
}
onKeyPress(e) {
if (e.code === "Enter") {
this.commitValue();
} else if (e.code === "Escape") {
this.switchMode("normal");
}
}
// Save the value from the field
commitValue() {
// copy the text from the input field to the element itself
this.textContent = this.input.value;
// dispatch an event to let the outside world we updated the text
this.dispatchEvent(new CustomEvent("update"));
// show the normal text
this.switchMode("normal");
}
// Show the input field or the static text according to the passed parameter
switchMode(mode) {
if (mode === "edit") {
this.span.style.display = "none";
this.div.style.display = "inline-block";
this.input.focus();
} else {
this.span.style.display = "inline-block";
this.div.style.display = "none";
}
}
// Return the HTML to populate our component. Note the usage of the `<slot>`
// tag: it references the child nodes of our web components
getHtml() {
return `
<span>
<slot></slot>
</span>
<div>
<input class="field"/>
</div>
`;
}
// Returns the style to use inside the shadow DOM. These rules will only affect
// the elements inside the shadow DOM!
getStyle() {
return `
:host {
cursor: pointer;
}
div {
display: none;
}
`;
}
// Nicely cleanup the event listeners when the node get disconnected
disconnectedCallback() {
this.span.removeEventListener("click", this.onTextClickedListener);
this.input.removeEventListener("blur", this.onInputBlurListener);
this.input.removeEventListener("keyup", this.onKeyPressListener);
}
}
// Declare our new web component
customElements.define("text-editable", TextEditable);
Also see: Tab Triggers