@surface/custom-element/internal/directives/event-directive.js

Provides support of directives and data binding on custom elements.

import { throwTemplateEvaluationError, tryEvaluateExpression, } from "../common.js";
export default class EventDirective {
    constructor(scope, element, descriptor) {
        this.name = descriptor.name;
        this.element = element;
        this.action = this.evaluate(scope, descriptor);
        this.element.addEventListener(this.name, this.action);
    }
    evaluate(scope, directive) {
        const action = tryEvaluateExpression(scope, directive.expression, directive.rawExpression, directive.stackTrace);
        if (!action) {
            throwTemplateEvaluationError(`Evaluation error in ${directive.rawExpression}: ${directive.expression} is not defined`, directive.stackTrace);
        }
        if (!(action instanceof Function)) {
            throwTemplateEvaluationError(`Evaluation error in ${directive.rawExpression}: ${directive.expression} is not a function`, directive.stackTrace);
        }
        return action;
    }
    dispose() {
        this.element.removeEventListener(this.name, this.action);
    }
}