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📄 EventDispatcher.js

📊 Analysis Summary

Metric	Count
🔧 Functions	4
🧱 Classes	1
📊 Variables & Constants	6

📚 Table of Contents

• Variables & Constants
• Functions
• Classes

🛠️ File Location:

📂 src/core/EventDispatcher.js

Variables & Constants

Name	Type	Kind	Value	Exported
listeners	{}	let/var	this._listeners	✗
listeners	{}	let/var	this._listeners	✗
listeners	{}	let/var	this._listeners	✗
listenerArray	any	let/var	listeners[ type ]	✗
listeners	{}	let/var	this._listeners	✗
listenerArray	any	let/var	listeners[ event.type ]	✗

---

Functions

EventDispatcher.addEventListener(type: string, listener: Function): void

JSDoc:

/**
     * Adds the given event listener to the given event type.
     *
     * @param {string} type - The type of event to listen to.
     * @param {Function} listener - The function that gets called when the event is fired.
     */

Parameters:

• type string
• listener Function

Returns: void

Calls:

• listeners[ type ].indexOf
• listeners[ type ].push

Code

addEventListener( type, listener ) {

        if ( this._listeners === undefined ) this._listeners = {};

        const listeners = this._listeners;

        if ( listeners[ type ] === undefined ) {

            listeners[ type ] = [];

        }

        if ( listeners[ type ].indexOf( listener ) === - 1 ) {

            listeners[ type ].push( listener );

        }

    }

EventDispatcher.hasEventListener(type: string, listener: Function): boolean

JSDoc:

/**
     * Returns `true` if the given event listener has been added to the given event type.
     *
     * @param {string} type - The type of event.
     * @param {Function} listener - The listener to check.
     * @return {boolean} Whether the given event listener has been added to the given event type.
     */

Parameters:

• type string
• listener Function

Returns: boolean

Calls:

• listeners[ type ].indexOf

Code

hasEventListener( type, listener ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return false;

        return listeners[ type ] !== undefined && listeners[ type ].indexOf( listener ) !== - 1;

    }

EventDispatcher.removeEventListener(type: string, listener: Function): void

JSDoc:

/**
     * Removes the given event listener from the given event type.
     *
     * @param {string} type - The type of event.
     * @param {Function} listener - The listener to remove.
     */

Parameters:

• type string
• listener Function

Returns: void

Calls:

• listenerArray.indexOf
• listenerArray.splice

Code

removeEventListener( type, listener ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return;

        const listenerArray = listeners[ type ];

        if ( listenerArray !== undefined ) {

            const index = listenerArray.indexOf( listener );

            if ( index !== - 1 ) {

                listenerArray.splice( index, 1 );

            }

        }

    }

EventDispatcher.dispatchEvent(event: any): void

JSDoc:

/**
     * Dispatches an event object.
     *
     * @param {Object} event - The event that gets fired.
     */

Parameters:

• event any

Returns: void

Calls:

• listenerArray.slice
• array[ i ].call

Internal Comments:

// Make a copy, in case listeners are removed while iterating. (x2)

Code

dispatchEvent( event ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return;

        const listenerArray = listeners[ event.type ];

        if ( listenerArray !== undefined ) {

            event.target = this;

            // Make a copy, in case listeners are removed while iterating.
            const array = listenerArray.slice( 0 );

            for ( let i = 0, l = array.length; i < l; i ++ ) {

                array[ i ].call( this, event );

            }

            event.target = null;

        }

    }

---

Classes

EventDispatcher

Class Code

class EventDispatcher {

    /**
     * Adds the given event listener to the given event type.
     *
     * @param {string} type - The type of event to listen to.
     * @param {Function} listener - The function that gets called when the event is fired.
     */
    addEventListener( type, listener ) {

        if ( this._listeners === undefined ) this._listeners = {};

        const listeners = this._listeners;

        if ( listeners[ type ] === undefined ) {

            listeners[ type ] = [];

        }

        if ( listeners[ type ].indexOf( listener ) === - 1 ) {

            listeners[ type ].push( listener );

        }

    }

    /**
     * Returns `true` if the given event listener has been added to the given event type.
     *
     * @param {string} type - The type of event.
     * @param {Function} listener - The listener to check.
     * @return {boolean} Whether the given event listener has been added to the given event type.
     */
    hasEventListener( type, listener ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return false;

        return listeners[ type ] !== undefined && listeners[ type ].indexOf( listener ) !== - 1;

    }

    /**
     * Removes the given event listener from the given event type.
     *
     * @param {string} type - The type of event.
     * @param {Function} listener - The listener to remove.
     */
    removeEventListener( type, listener ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return;

        const listenerArray = listeners[ type ];

        if ( listenerArray !== undefined ) {

            const index = listenerArray.indexOf( listener );

            if ( index !== - 1 ) {

                listenerArray.splice( index, 1 );

            }

        }

    }

    /**
     * Dispatches an event object.
     *
     * @param {Object} event - The event that gets fired.
     */
    dispatchEvent( event ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return;

        const listenerArray = listeners[ event.type ];

        if ( listenerArray !== undefined ) {

            event.target = this;

            // Make a copy, in case listeners are removed while iterating.
            const array = listenerArray.slice( 0 );

            for ( let i = 0, l = array.length; i < l; i ++ ) {

                array[ i ].call( this, event );

            }

            event.target = null;

        }

    }

}

Methods

addEventListener(type: string, listener: Function): void

Code

addEventListener( type, listener ) {

        if ( this._listeners === undefined ) this._listeners = {};

        const listeners = this._listeners;

        if ( listeners[ type ] === undefined ) {

            listeners[ type ] = [];

        }

        if ( listeners[ type ].indexOf( listener ) === - 1 ) {

            listeners[ type ].push( listener );

        }

    }

hasEventListener(type: string, listener: Function): boolean

Code

hasEventListener( type, listener ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return false;

        return listeners[ type ] !== undefined && listeners[ type ].indexOf( listener ) !== - 1;

    }

removeEventListener(type: string, listener: Function): void

Code

removeEventListener( type, listener ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return;

        const listenerArray = listeners[ type ];

        if ( listenerArray !== undefined ) {

            const index = listenerArray.indexOf( listener );

            if ( index !== - 1 ) {

                listenerArray.splice( index, 1 );

            }

        }

    }

dispatchEvent(event: any): void

Code

dispatchEvent( event ) {

        const listeners = this._listeners;

        if ( listeners === undefined ) return;

        const listenerArray = listeners[ event.type ];

        if ( listenerArray !== undefined ) {

            event.target = this;

            // Make a copy, in case listeners are removed while iterating.
            const array = listenerArray.slice( 0 );

            for ( let i = 0, l = array.length; i < l; i ++ ) {

                array[ i ].call( this, event );

            }

            event.target = null;

        }

    }

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