1 from Tkinter import *

     2 

     3 # this is the same as simple-demo-1.py, but uses

     4 # subclassing.

     5 # note that there is no explicit call to start Tk.

     6 # Tkinter is smart enough to start the system if it's not already going.

     7 

     8 class Test(Frame):

     9     def printit(self):

    10         print "hi"

    11 

    12     def createWidgets(self):

    13         self.QUIT = Button(self, text='QUIT',

    14                                   background='red',

    15                                   foreground='white',

    16                                   height=3,

    17                                   command=self.quit)

    18         self.QUIT.pack(side=BOTTOM, fill=BOTH)

    19 

    20         self.canvasObject = Canvas(self, width="5i", height="5i")

    21         self.canvasObject.pack(side=LEFT)

    22 

    23     def mouseDown(self, event):

    24         # canvas x and y take the screen coords from the event and translate

    25         # them into the coordinate system of the canvas object

    26         self.startx = self.canvasObject.canvasx(event.x, self.griddingSize)

    27         self.starty = self.canvasObject.canvasy(event.y, self.griddingSize)

    28 

    29     def mouseMotion(self, event):

    30         # canvas x and y take the screen coords from the event and translate

    31         # them into the coordinate system of the canvas object

    32         x = self.canvasObject.canvasx(event.x, self.griddingSize)

    33         y = self.canvasObject.canvasy(event.y, self.griddingSize)

    34 

    35         if (self.startx != event.x)  and (self.starty != event.y) :

    36             self.canvasObject.delete(self.rubberbandBox)

    37             self.rubberbandBox = self.canvasObject.create_rectangle(

    38                 self.startx, self.starty, x, y)

    39             # this flushes the output, making sure that

    40             # the rectangle makes it to the screen

    41             # before the next event is handled

    42             self.update_idletasks()

    43 

    44     def __init__(self, master=None):

    45         Frame.__init__(self, master)

    46         Pack.config(self)

    47         self.createWidgets()

    48 

    49         # this is a "tagOrId" for the rectangle we draw on the canvas

    50         self.rubberbandBox = None

    51 

    52         # this is the size of the gridding squares

    53         self.griddingSize = 50

    54 

    55         Widget.bind(self.canvasObject, "<Button-1>", self.mouseDown)

    56         Widget.bind(self.canvasObject, "<Button1-Motion>", self.mouseMotion)

    57 

    58 

    59 test = Test()

    60 

    61 test.mainloop()