Ext JS Observable Method Events

MethodEvents.js

(function() {

    // Private
    function addMethodEvent(options) {
        var method = this[options.method];
        var event = (options.prefix ? options.prefix + '_' : '') + options.method;
        function wrap() {
            this.fireEvent(event + '_start', this, arguments);
            this.fireEvent(event + '_end', this, arguments,
                method.apply(this, arguments));
        }
        this[options.method] = wrap;
    }

    Ext.define('Common.mixins.MethodEvents', {
        addMethodEvents: function() {
            var options;
            var argument;
            for (var i = 0, n = arguments.length; i < n; i++) {
                options = {
                    method: null,
                    prefix: ''
                }
                argument = arguments[i];
                if (Ext.isString(argument)) {
                    options.method = argument;
                } else {
                    Ext.apply(options, argument);
                }
                addMethodEvent.call(this, options);
            }
        }
    });

})();