jQuery widget call private function from event handler

jQuery widget call private function from event handler

I have a jQuery ui widget which has a link in it's content
<a href="test" data-foo="clickThis">Click me</a>
in _create function I attach click event handler and create instance variable
_create: function () {
//*this* here refers to widget
this.$elem.on('click', 'a[data-foo]', this._clickHandler);
this.instanceVariable = "someValue";
}
_clickHandler: function (event) {
//**this** in here refers to link, not to widget
//Question: How to call _otherPrivateFunction from here
}
_otherPrivateFunction(){
//I want to access this.instanceVariable in here
}
I have multiple instances of widget on one page, so each one should access
it's own instanceVariable. One way I found to do this, is to pass this as
event.data to the click handler, however I don't like this solution, as
this is just some workaround.
this.$elem.on('click', 'a[data-foo]', this, this._clickHandler);
I would appreciate some better solution.