from tkinter import *

class GUI :
    def __init__(self) :
        window = Tk()
        self.canvas = Canvas(window, height=300, width=400, bg="white")
        self.canvas.bind("<Button-1>", self.do_mousepress)
        self.canvas.bind("<ButtonRelease-1>", self.do_mouserelease)
        self.canvas.pack()
        button1 = Button(window, text="Action 1", command=self.do_action1)
        button1.pack()
        name_label = Label(window, text="Enter name").pack()
        self.name_field = Entry(window)
        self.name_field.pack()
        self.slider1 = Scale(window, from_=1, to=100, orient=HORIZONTAL, command=self.do_slider1)
        self.slider1.pack()
        window.mainloop()

    def do_mousepress(self,event) :
        # respond to mouse press event  (position at event.x, event.y)
        self.canvas.create_oval(event.x, event.y, event.x+20, event.y+20, fill="green")
        self.canvas.update()

    def do_mouserelease(self,event) :
        # respond to mouse press event  (position at event.x, event.y)
        self.canvas.create_rectangle(event.x, event.y, event.x+10, event.y+10, fill="red")
        self.canvas.update()

    def do_action1(self) :
        # respond to button 1
        # possibly accessing the text entry using: name_field.get()
        self.canvas.create_text(30, 200, text=self.name_field.get())
        self.canvas.update()

    def do_slider1(self,event) :
       # respond to slider being changed, using new value: slider1.get()
        self.canvas.delete(ALL)
        size = self.slider1.get()
        self.canvas.create_rectangle(10, 10, 10+size, 10+size, fill="blue")
        self.canvas.update()

GUI()