34-arrows.py

#

(C) Copyright 2024 Pavel Tisnovsky

All rights reserved. This program and the accompanying materials are made available under the terms of the Eclipse Public License v1.0 which accompanies this distribution, and is available at http://www.eclipse.org/legal/epl-v10.html

Contributors: Pavel Tisnovsky

link to source: https://github.com/tisnik/most-popular-python-libs/blob/master/PySimpleGUI/34-arrows.py

link to source in literate programming format: https://tisnik.github.io/most-popular-python-libs/PySimpleGUI/34-arrows.html

import tkinter

import PySimpleGUI as sg
#

kreslicí plátno

canvas = sg.Canvas(background_color="#ccffcc", size=(400, 400))


button_size = (10, 0)
#

ovládací prvky, které se mají zobrazit v okně

left_column = [
    [sg.Button("Draw lines", size=button_size)],
    [sg.Button("Draw ellipse", size=button_size)],
    [sg.Button("Draw polyline", size=button_size)],
    [sg.Button("Draw spline", size=button_size)],
    [sg.Button("Draw pieslices", size=button_size)],
    [sg.Button("Draw chords", size=button_size)],
    [sg.Button("Draw arrows", size=button_size)],
    [sg.Button("Clear canvas", size=button_size)],
    [sg.Button("Exit", size=button_size)],
]

right_column = [
    [canvas],
]

layout = [
    [
        sg.Frame("Commands", left_column),
        sg.Frame("Canvas", right_column),
    ],
]
#

Vykreslení úseček na plátno.

def draw_lines(canvas, tkcanvas):
#

zjistit aktuální velikost plátna

    size = canvas.get_size()
#

vykreslení tvarů

    tkcanvas.create_line(0, 0, size[0] - 1, size[1] - 1)
    tkcanvas.create_line(0, size[1] - 1, size[0] - 1, 0)
#

Vykreslení oválu na plátno.

def draw_ellipse(canvas, tkcanvas):
# 
    border = 5
#

zjistit aktuální velikost plátna

    size = canvas.get_size()
#

vykreslení tvarů

    tkcanvas.create_oval(border, border, size[0] - border, size[1] - border)
#

Vykreslení kruhových výsečí na plátno.

def draw_pieslices(canvas, tkcanvas):
# 
    tkcanvas.create_arc(1, 1, 100, 100, fill="#ff8080")
    tkcanvas.create_arc(100, 100, 200, 200, fill="#8080ff", start=45)
    tkcanvas.create_arc(200, 1, 300, 100, fill="#80ffff", extent=180)
    tkcanvas.create_arc(300, 100, 399, 199, fill="#ffff80", start=45, extent=270)

    tkcanvas.create_arc(1, 200, 100, 300, fill="#ff8080", start=90, extent=270)
    tkcanvas.create_arc(100, 300, 199, 399, fill="#8080ff", start=90 + 45, extent=270)
    tkcanvas.create_arc(200, 200, 299, 299, fill="#80ffff", start=180, extent=180)
    tkcanvas.create_arc(300, 300, 399, 399, fill="#ffff80", start=-45, extent=90)
#

Vykreslení kruhových úsečí na plátno.

def draw_chords(canvas, tkcanvas):
# 
    tkcanvas.create_arc(0, 0, 100, 100, fill="#ff8080", style=tkinter.CHORD)
    tkcanvas.create_arc(
        100, 100, 200, 200, fill="#8080ff", start=45, style=tkinter.CHORD
    )
    tkcanvas.create_arc(
        200, 0, 300, 100, fill="#80ffff", extent=180, style=tkinter.CHORD
    )
    tkcanvas.create_arc(
        300, 100, 399, 199, fill="#ffff80", start=45, extent=270, style=tkinter.CHORD
    )

    tkcanvas.create_arc(
        0, 200, 100, 300, fill="#ff8080", start=90, extent=270, style=tkinter.CHORD
    )
    tkcanvas.create_arc(
        100,
        300,
        199,
        399,
        fill="#8080ff",
        start=90 + 45,
        extent=270,
        style=tkinter.CHORD,
    )
    tkcanvas.create_arc(
        200, 200, 299, 299, fill="#80ffff", start=180, extent=180, style=tkinter.CHORD
    )
    tkcanvas.create_arc(
        300, 300, 399, 399, fill="#ffff80", start=-45, extent=90, style=tkinter.CHORD
    )
#

Vykreslení šipek.

def draw_arrows(canvas, tkcanvas):
# 
    tkcanvas.create_line(10, 50, 90, 50)
    tkcanvas.create_line(110, 50, 190, 50, arrow=tkinter.FIRST)
    tkcanvas.create_line(210, 50, 290, 50, arrow=tkinter.LAST)
    tkcanvas.create_line(310, 50, 390, 50, arrow=tkinter.BOTH)

    tkcanvas.create_line(10, 150, 90, 150, width=5)

    tkcanvas.create_line(110, 150, 190, 150, width=5, arrow=tkinter.FIRST)
    tkcanvas.create_line(210, 150, 290, 150, width=5, arrow=tkinter.LAST)
    tkcanvas.create_line(310, 150, 390, 150, width=5, arrow=tkinter.BOTH)

    tkcanvas.create_line(
        10, 250, 90, 250, width=2, arrow=tkinter.LAST, arrowshape=(10, 10, 10)
    )
    tkcanvas.create_line(
        110, 250, 190, 250, width=2, arrow=tkinter.LAST, arrowshape=(10, 20, 10)
    )
    tkcanvas.create_line(
        210, 250, 290, 250, width=2, arrow=tkinter.LAST, arrowshape=(10, 5, 10)
    )
    tkcanvas.create_line(
        310, 250, 390, 250, width=2, arrow=tkinter.LAST, arrowshape=(10, 0, 10)
    )

    tkcanvas.create_line(
        10, 350, 90, 350, width=2, arrow=tkinter.BOTH, arrowshape=(10, 10, 10)
    )
    tkcanvas.create_line(
        110, 350, 190, 350, width=2, arrow=tkinter.BOTH, arrowshape=(10, 20, 10)
    )
    tkcanvas.create_line(
        210, 350, 290, 350, width=2, arrow=tkinter.BOTH, arrowshape=(10, 5, 10)
    )
    tkcanvas.create_line(
        310, 350, 390, 350, width=2, arrow=tkinter.BOTH, arrowshape=(10, 0, 10)
    )
#

Vykreslení polyčáry na plátno.

def draw_polyline(canvas, tkcanvas, smooth):
# 
    border = 1
#

zjistit aktuální velikost plátna

    size = canvas.get_size()
#

vykreslení tvarů

    tkcanvas.create_line(
        border,
        size[1] - border,
        size[0] / 3,
        border,
        size[0] * 2 / 3,
        size[1] - border,
        size[0] - border,
        border,
        smooth=smooth,
    )
#

Vymazání všech objektů z kreslicího plátna.

def clear_canvas(tkcanvas):
# 
    tkcanvas.delete("all")
#

vytvoření okna s ovládacími prvky

window = sg.Window("Window #34", layout, use_custom_titlebar=False, finalize=True)
#

reference na plátno z knihovny Tk

tkcanvas = canvas.TKCanvas
#

obsluha smyčky událostí (event loop)

while True:
#

přečtení jediné události

    event, values = window.read()
    print("Event: ", event, "    Values: ", values)
#

reakce na událost “uzavření okna”

    if event in {"Exit", sg.WIN_CLOSED}:
        break
    elif event == "Draw lines":
        draw_lines(canvas, tkcanvas)
    elif event == "Draw ellipse":
        draw_ellipse(canvas, tkcanvas)
    elif event == "Draw polyline":
        draw_polyline(canvas, tkcanvas, False)
    elif event == "Draw spline":
        draw_polyline(canvas, tkcanvas, True)
    elif event == "Draw pieslices":
        draw_pieslices(canvas, tkcanvas)
    elif event == "Draw chords":
        draw_chords(canvas, tkcanvas)
    elif event == "Draw arrows":
        draw_arrows(canvas, tkcanvas)
    elif event == "Clear canvas":
        clear_canvas(tkcanvas)
    window.refresh()
#

po přečtení události okno zavřeme

window.close()