Attribute

function

Attribute()

Option name	Type	Description
el	Element	DOM element where attribute is attached
name	String	Optional name of the attribute, usually supplied by subclass via `attrName` method

An absctract class for parsing and validation of element attributes.
Subclasses should define methods attrName, parse, validate and render.

function Attribute(el, name) {
    this.name = name || this.attrName();
    this.el = el;

    // attribute node
    this.node = el.attributes[this.name];
}


_.extend(Attribute, {
    remove: Attribute$$remove
});

####Attribute instance methods####

get
set
decorate

The following instance methods should be defined by subclass

attrName - should return attribute name
parse - should parse attribute value
validate - should validate attribute value, throwing exception if it is incorrect
render - should return attribute value for a given attribute state (other properties, as defined in subclass)

_.extendProto(Attribute, {
    get: Attribute$get,
    set: Attribute$set,
    remove: Attribute$remove,
    decorate: Attribute$decorate,

    destroy: Attribute$destroy,

    // should be defined in subclass
    attrName: toBeImplemented,
    parse: toBeImplemented,
    validate: toBeImplemented,
    render: toBeImplemented
});


function Attribute$$remove(el, deep) {
    var name = this.prototype.attrName();
    el.removeAttribute(name);

    if (deep) {
        var selector = '[' + name + ']';
        var children = el.querySelectorAll(selector);
        _.forEach(children, function(childEl) {
            childEl.removeAttribute(name);
        });
    }
}


function Attribute$remove() {
    delete this.node;
}


function Attribute$destroy() {
    delete this.el;
    delete this.node;
}

Attribute$get

function

Attribute$get()

Attribute instance method that returns attribute value as string.

function Attribute$get() {
    return this.el.getAttribute(this.name);
}

Attribute$set

function

Attribute$set()

Option name	Type	Description
value	String

Attribute instance method that sets attribute value.

function Attribute$set(value) {
    this.el.setAttribute(this.name, value);
}

Attribute$decorate

function

Attribute$decorate()

Attribute instance method that decorates element with its rendered value.
Uses render method that should be defiend in subclass.

function Attribute$decorate() {
    this.set(this.render());
}


function toBeImplemented() {
    throw new Error('calling the method of an absctract class');
}