res.py

import tkinter as tk

class gradientFrame(tk.Frame):
    def __init__(self, parent):
        tk.Frame.__init__(self, parent)
        gradientBackground = GradientFrame(self, "green", "blue", borderwidth=1, relief="none")
        gradientBackground.pack(side="bottom", fill="both", expand=True)

class GradientFrame(tk.Canvas):
    '''A gradient frame which uses a canvas to draw the background'''
    def __init__(self, parent, color1="red", color2="black", **kwargs):
        tk.Canvas.__init__(self, parent, **kwargs)
        self._color1 = color1
        self._color2 = color2
        self.bind("<Configure>", self._draw_gradient)

    def _draw_gradient(self, event=None):
        '''Draw the gradient'''
        self.delete("gradient")
        width = self.winfo_width()
        height = self.winfo_height()
        limit = width
        (r1,g1,b1) = self.winfo_rgb(self._color1)
        (r2,g2,b2) = self.winfo_rgb(self._color2)
        r_ratio = float(r2-r1) / limit
        g_ratio = float(g2-g1) / limit
        b_ratio = float(b2-b1) / limit

        for i in range(limit):
            nr = int(r1 + (r_ratio * i))
            ng = int(g1 + (g_ratio * i))
            nb = int(b1 + (b_ratio * i))
            color = "#%4.4x%4.4x%4.4x" % (nr,ng,nb)
            self.create_line(i,0,i,height, tags=("gradient",), fill=color)
        self.lower("gradient")