Introduction

I longed for a professor's drawing app and wondered if I could do something myself.

Complete system

How to make

Canvas method

import tkinter class Scribble:

--Left-click to draw a dot --Sx.sy is currently located

   
    def on_pressed(self, event):
        self.sx = event.x
        self.sy = event.y
        self.canvas.create_oval(self.sx, self.sy, event.x, event.y,
                                outline = self.color.get(),
                                width = self.width.get())

--Draw a line between the coordinates just before dragging


　　def on_dragged(self, event):
        self.canvas.create_line(self.sx, self.sy, event.x, event.y,
                            fill = self.color.get(),
                            width = self.width.get())
        self.sx = event.x
        self.sy = event.y

--Click in the middle to make a circle, right-click to make an ellipse


    def click1(self,event):
        self.canvas.create_oval(self.sx-20,self.sy-20,self.sx+20,self.sy+20,
                            fill = self.color.get(),
                            width = self.width.get())

    def click2(self,event):
        self.canvas.create_oval(self.sx-40,self.sy-30,self.sx+40,self.sy+30,
                           fill = self.color.get(),
                           width = self.width.get())

Make a window

--End program with button object


    def create_window(self):
        window = tkinter.Tk()
        window.title("Drawing software")
        self.canvas = tkinter.Canvas(window, bg = "black", 
                                 width = 600, height = 400)                             
        self.canvas.pack()
        quit_button = tkinter.Button(window, text = "End",
                                 command = window.quit)
        quit_button.pack(side = tkinter.RIGHT)

        self.canvas.bind("<ButtonPress-1>", self.on_pressed)
        self.canvas.bind("<B1-Motion>", self.on_dragged)
        self.canvas.bind("<ButtonPress-2>",self.click1)
        self.canvas.bind("<ButtonPress-3>",self.click2)

Color change

--Place option menu object in window


        COLORS = ["red", "white", "blue", "pink", "green","black"]
        self.color = tkinter.StringVar()                    
        self.color.set(COLORS[1])                             
        b = tkinter.OptionMenu(window, self.color, *COLORS) 
        b.pack(side = tkinter.LEFT)

Change line thickness

--Place scale object in window


        self.width = tkinter.Scale(window, from_ = 1, to = 10,
                               orient = tkinter.HORIZONTAL) 
        self.width.set(5)                                       
        self.width.pack(side = tkinter.LEFT)

        return window;

    def __init__(self):
        self.window = self.create_window();  

    def run(self):
        self.window.mainloop()
Scribble().run()

Complete program


import tkinter

class Scribble:
    
    def on_pressed(self, event):
        self.sx = event.x
        self.sy = event.y
        self.canvas.create_oval(self.sx, self.sy, event.x, event.y,
                                outline = self.color.get(),
                                width = self.width.get())


    def on_dragged(self, event):
        self.canvas.create_line(self.sx, self.sy, event.x, event.y,
                            fill = self.color.get(),
                            width = self.width.get())
        self.sx = event.x
        self.sy = event.y

    def click1(self,event):
        self.canvas.create_oval(self.sx-20,self.sy-20,self.sx+20,self.sy+20,
                            fill = self.color.get(),
                            width = self.width.get())

    def click2(self,event):
        self.canvas.create_oval(self.sx-40,self.sy-30,self.sx+40,self.sy+30,
                           fill = self.color.get(),
                           width = self.width.get())



    def create_window(self):
        window = tkinter.Tk()
        window.title("Drawing software")
        self.canvas = tkinter.Canvas(window, bg = "black", 
                                 width = 600, height = 400)                             
        self.canvas.pack()
        quit_button = tkinter.Button(window, text = "End",
                                 command = window.quit)
        quit_button.pack(side = tkinter.RIGHT)

        self.canvas.bind("<ButtonPress-1>", self.on_pressed)
        self.canvas.bind("<B1-Motion>", self.on_dragged)
        self.canvas.bind("<ButtonPress-2>",self.click1)
        self.canvas.bind("<ButtonPress-3>",self.click2)



        COLORS = ["red", "white", "blue", "pink", "green","black"]
        self.color = tkinter.StringVar()                    
        self.color.set(COLORS[1])                             
        b = tkinter.OptionMenu(window, self.color, *COLORS) 
        b.pack(side = tkinter.LEFT)


        self.width = tkinter.Scale(window, from_ = 1, to = 10,
                               orient = tkinter.HORIZONTAL) 
        self.width.set(5)                                       
        self.width.pack(side = tkinter.LEFT)

        return window;

    def __init__(self):
        self.window = self.create_window();  

    def run(self):
        self.window.mainloop()
Scribble().run()

https://www.nslabs.jp/monkey-python-02b.rhtml I was allowed to refer to.

I tried to draw with three mouse buttons.

Finally

I wanted to add a button to go back one step and a freehand correction function, but I couldn't add the code very much because I couldn't understand the code. I want to focus on Python during the summer vacation and enjoy the fun I can do on my own.

References

https://www.nslabs.jp/monkey-python-02b.rhtml