macOS I would like to make a widget clock, any source, books or tips?

[blueroom]

I'd like to make a widget clock, very much like the clock that comes with OSX but a 24 hr and variable colored background depending on the time of day.
Any suggestions on where to start?

 

[kainjow]

What do you mean by widget? Dashboard widget?

 

[applerocks123]

Dashboard

if your talking about a dashboard wiget you have to download xcode