Moving widgets in Tkinter

[Eric Brunel]

Adonis wrote:
> I wish to manually move widgets in Tkinter, now I have successfully done it,
> but with odd results, I would like to move the widgets with a much smoother
> manner, and better precision.
> 
> Any help is greatly appreciated.
> 
> --
> 
> here is snip of working code:
> 
> from Tkinter import *
> 
> class blah:
> 
>     def MoveWindow(self, event):
>         self.root.update_idletasks()
>         self.f.place_configure(x=event.x_root, y=event.y_root-20)

event.x_root & event.y_root will give you the coordinates of the event in the 
*screen*, which is apparently not what you want. The name "root" traditionally 
used for Tkinter main windows is somewhat confusing here: the window called 
"root" in tk/Tkinter methods is the screen, not your main window.

>     def __init__(self):
>         self.root = Tk()
>         self.root.title("...")
>         self.root.resizable(0,0)
>         self.root.geometry("%dx%d%+d%+d"%(640, 480, 0, 0))
> 
>         self.f = Frame(self.root, bd=1, relief=SUNKEN)
>         self.f.place(x=0, y=0, width=200, height=200)
> 
>         self.l = Label(self.f, bd=1, relief=RAISED, text="Test")
>         self.l.pack(fill=X, padx=1, pady=1)
> 
>         self.l.bind('<B1-Motion>', self.MoveWindow)
>         self.f.bind('<B1-Motion>', self.MoveWindow)
> 
>         self.root.mainloop()
> 
> x = blah()

Doing what you want is a bit more complicated than what you've already done: the 
best way to use event.x_root and event.y_root here is relatively to a former 
recorded position. What I'd do would be the following:

-----------------------------------------
from Tkinter import *

class blah:

     def startMoveWindow(self, event):
         ## When the movement starts, record current root coordinates
         self.__lastX, self.__lastY = event.x_root, event.y_root

     def MoveWindow(self, event):
         self.root.update_idletasks()
         ## Use root coordinates to compute offset for inside window coordinates
         self.__winX += event.x_root - self.__lastX
         self.__winY += event.y_root - self.__lastY
         ## Remember last coordinates
         self.__lastX, self.__lastY = event.x_root, event.y_root
         ## Move inside window
         self.f.place_configure(x=self.__winX, y=self.__winY)

     def __init__(self):
         self.root = Tk()
         self.root.title("...")
         self.root.resizable(0,0)
         self.root.geometry("%dx%d%+d%+d"%(640, 480, 0, 0))

         ## Record coordinates for window to avoid asking them every time
         self.__winX, self.__winY = 0, 0
         self.f = Frame(self.root, bd=1, relief=SUNKEN)
         self.f.place(x=self.__winX, y=self.__winY, width=200, height=200)

         self.l = Label(self.f, bd=1, relief=RAISED, text="Test")
         self.l.pack(fill=X, padx=1, pady=1)

         ## When the button is pressed, make sure we get the first coordinates
         self.l.bind('<ButtonPress-1>', self.startMoveWindow)
         self.l.bind('<B1-Motion>', self.MoveWindow)
         self.f.bind('<ButtonPress-1>', self.startMoveWindow)
         self.f.bind('<B1-Motion>', self.MoveWindow)

         self.root.mainloop()

x = blah()
-----------------------------------------

HTH
-- 
- Eric Brunel <eric dot brunel at pragmadev dot com> -
PragmaDev : Real Time Software Development Tools - http://www.pragmadev.com