How to decide between _init and _create in jQuery UI widget?

Luke Maurer picture Luke Maurer · Dec 30, 2010 · Viewed 11k times · Source

I think I understand the difference between _create and _init in widget definitions (see for instance this question), but I'm still not certain about the purpose for the distinction. What sorts of setup tasks go in _create() or in _init()? What goes wrong if the widget author chooses the wrong one?

Answer

Dave Jarvis picture Dave Jarvis · Jan 3, 2011

From:

Use _create to build and inject markup, bind events, etc. Place default functionality in _init(). The dialog widget, for example, provides an autoOpen parameter denoting whether or not the dialog should be open once the widget is initialized; a perfect spot for _init()!

Also:

The widget factory automatically fires the _create() and _init() methods during initialization, in that order. At first glance it appears that the effort is duplicated, but there is a sight difference between the two. Because the widget factory protects against multiple instantiations on the same element, _create() will be called a maximum of one time for each widget instance, whereas _init() will be called each time the widget is called without arguments...

If the author uses _init() when _create() should have been coded, the result will be that the code in _init() will be executed once per widget instantiation.