Python/tkinter window manager

WindowManager.py

# The MIT License (MIT)

# Copyright (c) 2014 Alex Zylstra

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# THE SOFTWARE.

__author__ = 'Alex Zylstra'
__date__ = '2014-03-26'
__version__ = '1.0.0'

import tkinter as tk
import numpy as np
import scipy, scipy.signal
import re

def parseGeometry(geometry):
"""Parse a tkinter geometry string.

:param geometry: A geometry string from `Toplevel.geometry`
:returns: A list containing [width, height, x, y]
"""
m = re.match("(\d+)x(\d+)([-+]\d+)([-+]\d+)", geometry)
if not m:
    raise ValueError("failed to parse geometry string")
return list(map(int, m.groups()))

class WindowManager:
"""Window management functionality. This class acts as a manager for placement of all windows
created by modules and implosions via one of a few methods.

:param screenWidth: The width of the screen in pixels
:param screenHeight: The height of the screen in pixels
:author: Alex Zylstra
:date: 2014-03-26
"""
#: Step size in horizontal placement [pixels]
dx = 10
#: Step size in vertical placement [pixels]
dy = 10

def __init__(self, screenWidth, screenHeight):
    """Constructor for a new window manager."""
    self.windows = []
    self.screenWidth = screenWidth
    self.screenHeight = screenHeight

def getLocation(self, width, height):
    """Get a location for a new window of specified size. Units in pixels.

    :param width: The width of the window
    :param height: The height of the window
    :returns: tuple containing coordinates (x,y)
    """
    usageMatrix = np.ones((self.screenHeight/20,self.screenWidth/20), dtype=np.float32)

    for w in self.windows:
        # Wrap in try/except block in case windows are totally deleted
        try:
            assert isinstance(w, tk.Toplevel) or isinstance(w, tk.Tk)
            if w.wm_state() == 'normal':
                g = parseGeometry(w.geometry())
                # width of extra window stuff including title bar:
                borderx = w.winfo_rootx() - g[2]
                bordery = w.winfo_rooty() - g[3]

                x = np.floor(g[2]/20)
                y = np.floor((g[3])/20)
                w = np.ceil((g[0]+borderx)/20)
                h = np.ceil((g[1]+bordery)/20)
                usageMatrix[y:y+h,x:x+w] = 0
        except tk.TclError:
            self.windows.remove(w)
        except Exception as e:
            print('An exception occurred in WindowManager.getLocation: ', e)
            pass
         
    b = np.ones((height/20,width/20), dtype=np.float32)
    loc_ok = (scipy.signal.convolve2d(usageMatrix, b, 'valid') == int(width/20)*int(height/20))
    try:
        new_loc = np.argwhere(loc_ok)[0]
        return 20*new_loc[1], 20*new_loc[0]
    except Exception as e:
        print('An exception occurred in WindowManager.getLocation: ', e)
        return 0,0

def addWindow(self, w, passive=False):
    """Add a new window.

    :param w: The new window (must be a :py:class:`tkinter.Toplevel` object)
    :param passive: (optional) if set to True, the `WindowManager` will not change the current placement of w.
    """
    assert isinstance(w, tk.Toplevel) or isinstance(w, tk.Tk)

    w.update_idletasks()

    # if requested, place the window:
    if not passive:
        # Get the width and height, then use the other function in this class to get a spot to put it:
        g = parseGeometry(w.geometry())
        width = g[0]
        height = g[1]
        x,y = self.getLocation(width, height)
        # place:
        w.geometry("%dx%d%+d%+d" % (width, height, x, y))
        w.update_idletasks()

    # add to the internal list of managed windows:
    self.windows.append(w)