1from Tkinter import *
2
3# this file demonstrates the creation of widgets as part of a canvas object
4
5class Test(Frame):
6    ###################################################################
7    ###### Event callbacks for THE CANVAS (not the stuff drawn on it)
8    ###################################################################
9    def mouseDown(self, event):
10        # see if we're inside a dot. If we are, it
11        # gets tagged as CURRENT for free by tk.
12
13        if not event.widget.find_withtag(CURRENT):
14            # there is no dot here, so we can make one,
15            # and bind some interesting behavior to it.
16            # ------
17            # create a dot, and mark it as current
18            fred = self.draw.create_oval(
19                event.x - 10, event.y -10, event.x +10, event.y + 10,
20                fill="green")
21            self.draw.tag_bind(fred, "<Enter>", self.mouseEnter)
22            self.draw.tag_bind(fred, "<Leave>", self.mouseLeave)
23        self.lastx = event.x
24        self.lasty = event.y
25
26    def mouseMove(self, event):
27        self.draw.move(CURRENT, event.x - self.lastx, event.y - self.lasty)
28        self.lastx = event.x
29        self.lasty = event.y
30
31    ###################################################################
32    ###### Event callbacks for canvas ITEMS (stuff drawn on the canvas)
33    ###################################################################
34    def mouseEnter(self, event):
35        # the "current" tag is applied to the object the cursor is over.
36        # this happens automatically.
37        self.draw.itemconfig(CURRENT, fill="red")
38        print self.draw.coords(CURRENT)
39
40    def mouseLeave(self, event):
41        # the "current" tag is applied to the object the cursor is over.
42        # this happens automatically.
43        self.draw.itemconfig(CURRENT, fill="blue")
44
45    def createWidgets(self):
46        self.QUIT = Button(self, text='QUIT', foreground='red',
47                           command=self.quit)
48        self.QUIT.pack(side=LEFT, fill=BOTH)
49        self.draw = Canvas(self, width="5i", height="5i")
50        self.draw.pack(side=LEFT)
51
52        Widget.bind(self.draw, "<1>", self.mouseDown)
53        Widget.bind(self.draw, "<B1-Motion>", self.mouseMove)
54
55    def __init__(self, master=None):
56        Frame.__init__(self, master)
57        Pack.config(self)
58        self.createWidgets()
59
60test = Test()
61test.mainloop()
62