cpython/Demo/tkinter/matt/canvas-moving-or-creating.py

71 lines
2.2 KiB
Python

from Tkinter import *
# this file demonstrates a more sophisticated movement --
# move dots or create new ones if you click outside the dots
class Test(Frame):
###################################################################
###### Event callbacks for THE CANVAS (not the stuff drawn on it)
###################################################################
def mouseDown(self, event):
# see if we're inside a dot. If we are, it
# gets tagged as "current" for free by tk.
if not event.widget.find_withtag("current"):
# there is no dot here, so we can make one,
# and bind some interesting behavior to it.
# ------
# create a dot, and mark it as current
fred = self.draw.create_oval(event.x - 10, event.y -10, event.x +10, event.y + 10,
{"fill" : "green", "tag" : "current"})
self.draw.bind(fred, "<Any-Enter>", self.mouseEnter)
self.draw.bind(fred, "<Any-Leave>", self.mouseLeave)
self.lastx = event.x
self.lasty = event.y
def mouseMove(self, event):
self.draw.move("current", event.x - self.lastx, event.y - self.lasty)
self.lastx = event.x
self.lasty = event.y
###################################################################
###### Event callbacks for canvas ITEMS (stuff drawn on the canvas)
###################################################################
def mouseEnter(self, event):
# the "current" tag is applied to the object the cursor is over.
# this happens automatically.
self.draw.itemconfig("current", {"fill" : "red"})
def mouseLeave(self, event):
# the "current" tag is applied to the object the cursor is over.
# this happens automatically.
self.draw.itemconfig("current", {"fill" : "blue"})
def createWidgets(self):
self.QUIT = Button(self, {'text': 'QUIT',
'fg': 'red',
'command': self.quit})
self.QUIT.pack({'side': 'left', 'fill': 'both'})
self.draw = Canvas(self, {"width" : "5i", "height" : "5i"})
self.draw.pack({'side': 'left'})
Widget.bind(self.draw, "<1>", self.mouseDown)
Widget.bind(self.draw, "<B1-Motion>", self.mouseMove)
def __init__(self, master=None):
Frame.__init__(self, master)
Pack.config(self)
self.createWidgets()
test = Test()
test.mainloop()