DotView

A simple one-window demo showing how to custom drawing in a custom NSView. Additionally shows how easy it is to embed a view in an NSScrollView, as well as how to use an NSColorWell.

Sources

DotView.py

"""DotView.py -- A one-window app demonstrating how to write a custom NSView.

To build the demo program, run this line in Terminal.app:

    $ python setup.py py2app -A

This creates a directory "dist" containing DotView.app. (The
-A option causes the files to be symlinked to the .app bundle instead
of copied. This means you don't have to rebuild the app if you edit the
sources or nibs.)
"""

# Created by Etienne Posthumus on Thu Dec 26 2002, after Apple's
# ObjC DotView example.
# Edited and enhanced by JvR, 2003.
#
# The main difference with the Apple DotView demo is that our custom view
# is embedded in a scroll view. It turns out that this is almost no work
# in InterfaceBuilder (select the view, then go to Layout -> Make subvies of
# -> Scroll View), and *no* work in the code. It was too easy, so for kicks
# I added zoom functionality and a "Show rulers" checkbox.

import objc
from objc import super
import Cocoa
from PyObjCTools import AppHelper

ZOOM = 2.0


# class defined in MainMenu.nib
class DotView(Cocoa.NSView):
    colorWell = objc.IBOutlet()
    sizeSlider = objc.IBOutlet()

    def initWithFrame_(self, frame):
        self.center = (50.0, 50.0)
        super(DotView, self).initWithFrame_(frame)
        self.radius = 10.0
        self.color = Cocoa.NSColor.redColor()
        return self

    def awakeFromNib(self):
        self.colorWell.setColor_(self.color)
        self.sizeSlider.setFloatValue_(self.radius)
        scrollView = self.superview().superview()
        scrollView.setHasHorizontalRuler_(1)
        scrollView.setHasVerticalRuler_(1)

    @objc.IBAction
    def zoomIn_(self, sender):
        (x, y), (bw, bh) = self.bounds()
        (x, y), (fw, fh) = self.frame()
        self.setBoundsSize_((bw / ZOOM, bh / ZOOM))
        self.setFrameSize_((fw * ZOOM, fh * ZOOM))
        self.setNeedsDisplay_(True)

    @objc.IBAction
    def zoomOut_(self, sender):
        (x, y), (bw, bh) = self.bounds()
        (x, y), (fw, fh) = self.frame()
        self.setBoundsSize_((bw * ZOOM, bh * ZOOM))
        self.setFrameSize_((fw / ZOOM, fh / ZOOM))
        self.setNeedsDisplay_(True)

    @objc.IBAction
    def setRulersVisible_(self, button):
        scrollView = self.superview().superview()
        scrollView.setRulersVisible_(button.state())

    def isOpaque(self):
        return True

    def mouseDown_(self, event):
        eventLocation = event.locationInWindow()
        if event.modifierFlags() & Cocoa.NSCommandKeyMask:
            clipView = self.superview()
            self.originalPoint = eventLocation
            self.originalOffset = clipView.bounds()[0]
        else:
            self.center = self.convertPoint_fromView_(eventLocation, None)
            self.setNeedsDisplay_(True)
            self.autoscroll_(event)

    def mouseDragged_(self, event):
        if event.modifierFlags() & Cocoa.NSCommandKeyMask:
            clipView = self.superview()
            eventLocation = event.locationInWindow()
            ox, oy = self.originalPoint
            x, y = eventLocation
            dx, dy = x - ox, y - oy
            x, y = self.originalOffset
            ox, oy = clipView.constrainScrollPoint_((x - dx, y - dy))
            clipView.scrollToPoint_((ox, oy))
            clipView.superview().reflectScrolledClipView_(clipView)
        else:
            self.mouseDown_(event)

    def drawRect_(self, rect):
        Cocoa.NSColor.whiteColor().set()
        Cocoa.NSRectFill(self.bounds())
        origin = (self.center[0]-self.radius, self.center[1]-self.radius)
        size = (2 * self.radius, 2 * self.radius)
        dotRect = (origin, size)
        self.color.set()
        Cocoa.NSBezierPath.bezierPathWithOvalInRect_(dotRect).fill()

    @objc.IBAction
    def setRadius_(self, sender):
        self.radius = sender.floatValue()
        self.setNeedsDisplay_(True)

    @objc.IBAction
    def setColor_(self, sender):
        self.color = sender.color()
        self.setNeedsDisplay_(True)


if __name__ == "__main__":
    AppHelper.runEventLoop()

setup.py

"""
Script for building the example.

Usage:
    python3 setup.py py2app
"""
from setuptools import setup

setup(
    name="DotView",
    app=["DotView.py"],
    data_files=["English.lproj"],
    setup_requires=[
        "py2app",
        "pyobjc-framework-Cocoa",
    ]
)

Resources