| Guido van Rossum | 35820f7 | 1994-10-07 09:55:26 +0000 | [diff] [blame^] | 1 | from Tkinter import * |
| 2 | |
| 3 | # allows moving dots with multiple selection. |
| 4 | |
| 5 | SELECTED_COLOR = "red" |
| 6 | UNSELECTED_COLOR = "blue" |
| 7 | |
| 8 | class Test(Frame): |
| 9 | ################################################################### |
| 10 | ###### Event callbacks for THE CANVAS (not the stuff drawn on it) |
| 11 | ################################################################### |
| 12 | def mouseDown(self, event): |
| 13 | # see if we're inside a dot. If we are, it |
| 14 | # gets tagged as "current" for free by tk. |
| 15 | |
| 16 | if not event.widget.find_withtag("current"): |
| 17 | # we clicked outside of all dots on the canvas. unselect all. |
| 18 | |
| 19 | # re-color everything back to an unselected color |
| 20 | self.draw.itemconfig("selected", {"fill" : UNSELECTED_COLOR}) |
| 21 | # unselect everything |
| 22 | self.draw.dtag("selected") |
| 23 | else: |
| 24 | # mark as "selected" the thing the cursor is under |
| 25 | self.draw.addtag("selected", "withtag", "current") |
| 26 | # color it as selected |
| 27 | self.draw.itemconfig("selected", {"fill": SELECTED_COLOR}) |
| 28 | |
| 29 | self.lastx = event.x |
| 30 | self.lasty = event.y |
| 31 | |
| 32 | |
| 33 | def mouseMove(self, event): |
| 34 | self.draw.move("selected", event.x - self.lastx, event.y - self.lasty) |
| 35 | self.lastx = event.x |
| 36 | self.lasty = event.y |
| 37 | |
| 38 | def makeNewDot(self): |
| 39 | # create a dot, and mark it as current |
| 40 | fred = self.draw.create_oval(0, 0, 20, 20, |
| 41 | {"fill" : SELECTED_COLOR, "tag" : "current"}) |
| 42 | # and make it selected |
| 43 | self.draw.addtag("selected", "withtag", "current") |
| 44 | |
| 45 | def createWidgets(self): |
| 46 | self.QUIT = Button(self, {'text': 'QUIT', |
| 47 | 'fg': 'red', |
| 48 | 'command': self.quit}) |
| 49 | |
| 50 | ################ |
| 51 | # make the canvas and bind some behavior to it |
| 52 | ################ |
| 53 | self.draw = Canvas(self, {"width" : "5i", "height" : "5i"}) |
| 54 | Widget.bind(self.draw, "<1>", self.mouseDown) |
| 55 | Widget.bind(self.draw, "<B1-Motion>", self.mouseMove) |
| 56 | |
| 57 | |
| 58 | # and other things..... |
| 59 | self.button = Button(self, {"text" : "make a new dot", |
| 60 | "command" : self.makeNewDot, |
| 61 | "fg" : "blue"}) |
| 62 | |
| 63 | self.label = Message(self, |
| 64 | {"width" : "5i", |
| 65 | "text" : SELECTED_COLOR + " dots are selected and can be dragged.\n" + |
| 66 | UNSELECTED_COLOR + " are not selected.\n" + |
| 67 | "Click in a dot to select it.\n" + |
| 68 | "Click on empty space to deselect all dots." }) |
| 69 | |
| 70 | self.QUIT.pack({'side': 'bottom', 'fill': 'both'}) |
| 71 | self.label.pack({"side" : "bottom", "fill" : "x", "expand" : 1}) |
| 72 | self.button.pack({"side" : "bottom", "fill" : "x"}) |
| 73 | self.draw.pack({'side': 'left'}) |
| 74 | |
| 75 | |
| 76 | def __init__(self, master=None): |
| 77 | Frame.__init__(self, master) |
| 78 | Pack.config(self) |
| 79 | self.createWidgets() |
| 80 | |
| 81 | test = Test() |
| 82 | test.mainloop() |
| 83 | |
| 84 | |
| 85 | |