/Demo/tkinter/matt/rubber-line-demo-1.py

 1from Tkinter import *
 2
 3class Test(Frame):
 4    def printit(self):
 5        print "hi"
 6
 7    def createWidgets(self):
 8        self.QUIT = Button(self, text='QUIT',
 9                                  background='red',
10                                  foreground='white',
11                                  height=3,
12                                  command=self.quit)
13        self.QUIT.pack(side=BOTTOM, fill=BOTH)
14
15        self.canvasObject = Canvas(self, width="5i", height="5i")
16        self.canvasObject.pack(side=LEFT)
17
18    def mouseDown(self, event):
19        # canvas x and y take the screen coords from the event and translate
20        # them into the coordinate system of the canvas object
21        self.startx = self.canvasObject.canvasx(event.x)
22        self.starty = self.canvasObject.canvasy(event.y)
23
24    def mouseMotion(self, event):
25        # canvas x and y take the screen coords from the event and translate
26        # them into the coordinate system of the canvas object
27        x = self.canvasObject.canvasx(event.x)
28        y = self.canvasObject.canvasy(event.y)
29
30        if (self.startx != event.x)  and (self.starty != event.y) :
31            self.canvasObject.delete(self.rubberbandLine)
32            self.rubberbandLine = self.canvasObject.create_line(
33                self.startx, self.starty, x, y)
34            # this flushes the output, making sure that
35            # the rectangle makes it to the screen
36            # before the next event is handled
37            self.update_idletasks()
38
39    def __init__(self, master=None):
40        Frame.__init__(self, master)
41        Pack.config(self)
42        self.createWidgets()
43        # this is a "tagOrId" for the rectangle we draw on the canvas
44        self.rubberbandLine = None
45        Widget.bind(self.canvasObject, "<Button-1>", self.mouseDown)
46        Widget.bind(self.canvasObject, "<Button1-Motion>", self.mouseMotion)
47
48
49test = Test()
50
51test.mainloop()