Back in ExtJS 5 Sencha rolled out a rather cool concept of declarative listeners, where you could write something like this:
{ xtype: 'button', handler: 'onButtonClick' } |
…note that onButtonClick is a string, rather than a function reference. The idea here is that the actual function would be resolved at runtime and will be located somewhere in the ViewController world. It was described well by Don Griffin in his blog post: https://www.sencha.com/blog/using-viewcontrollers-in-ext-js-5/.
However, what was omitted in this blog post and the guides, is the potentially powerful and risky “up the component tree” resolution of the ViewController. Read on to learn more with a Sencha Fiddle example…