a lot of issue 
what is color?
a vanilla colorWell is not callable, most vanilla controls have .get() to retrieve the data of the control.
import vanilla
import drawBot
from AppKit import NSColor
# create a custom controller calss
class MyController:
def __init__(self):
# use vanilla to create a window
self.w = vanilla.Window((800, 800), minSize=(200, 200))
# add a text box
self.w.textSizeText = vanilla.TextBox((10, 10, -10, 22), "Text Size:")
# add a slider
self.w.textSize = vanilla.Slider((80, 10, -10, 22), value=20, minValue=8, maxValue=50)
# add a button and set the hit callback to `drawIt`
self.w.update = vanilla.Button((150, 40, -150, 22), "Update", callback=self.drawIt)
self.w.colors = vanilla.ColorWell((10, 60, -750, -700),color=NSColor.redColor())
self.w.checkBox = vanilla.CheckBox((60, 80, -10, 20), "use color", value=True)
# add a drawBot preview
self.w.preview = drawBot.ui.drawView.DrawView((0, 120, 0, 0))
self.w.open() # open the window
def drawIt(self, sender):
# the callback when ever the button is hit
# get the font size from the slider
fontSize = self.w.textSize.get()
# start a new drawing
drawBot.newDrawing()
# add a page
drawBot.newPage(100, 100)
# set a font size
drawBot.fontSize(fontSize)
# draw some thext
drawBot.text(f"{fontSize}pt Hello foo bar", (10, 10))
if self.w.checkBox.get():
color = self.w.colors.get()
else:
color = 0
fill(color)
rect(0,50,self.w.textSize.get(), 30)
# get the pdf document
pdf = drawBot.pdfImage()
# set the pdf document in the preview
self.w.preview.setPDFDocument(pdf)
# clean up
drawBot.endDrawing()
# open your controller
MyController()
