Staff

Example Python program Staff.py This program creates a PyQt GUI

Modules

• from PyQt5.QtWidgets import *
• from PyQt5.QtGui import *
• from PyQt5.QtCore import *
• from random import random, randint
• import sys

Classes

• class StaffMainWindow(QWidget):

Methods

• def init(self):
• def initUI(self):
• def draw_note(self, qp, hl, pos_n, pos_x):
• def paintEvent(self, e):
• def keyPressEvent(self, e):

Code

Example Python PyQt program :

from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
from PyQt5.QtCore import *

from random import random, randint

import sys


class StaffMainWindow(QWidget):
    def __init__(self):
        super().__init__()

        self.request_width = 1000
        self.request_height = 500

        self.line_width = 1
        self.line_spacing = 10
        self.hl_spacing = 120
        self.stub_width = 20
        self.stf_top = 100

        self.h_mid = self.stf_top + self.line_spacing * 2
        self.l_mid = self.stf_top + self.line_spacing * 6 + self.hl_spacing

        self.s_name = ['do', 're', 'mi', 'fa', 'so', 'la', 'si']
        self.n_name = ['C', 'D', 'E', 'F', 'G', 'A', 'B']

        self.is_h = True
        self.is_show = False
        self.pos_x = 0
        self.level = 0

        self.cur_s_name = 'do'
        self.cur_n_name = 'C'
        self.cur_level_name = 1

        self.initUI()

    def initUI(self):
        self.setGeometry(0, 0, self.request_width, self.request_height)
        self.setWindowTitle('Staff')
        self.show()

    def draw_note(self, qp, hl, pos_n, pos_x):
        if hl == 'h':
            cur_mid = self.h_mid
        else:
            cur_mid = self.l_mid

        if pos_n > 0:
            for i in range(7):
                if i <= pos_n:
                    qp.drawRect(pos_x, cur_mid - i*self.line_spacing, self.stub_width, self.line_width)
                else:
                    break
        else:
            for i in range(7):
                if -i >= pos_n:
                    qp.drawRect(pos_x, cur_mid + i * self.line_spacing, self.stub_width, self.line_width)
                else:
                    break
        qp.drawEllipse(pos_x + int(self.stub_width*0.1), cur_mid - int(pos_n * self.line_spacing)
                       - int(self.line_spacing*0.5),
                       int(self.stub_width*0.8), int(self.line_spacing*0.9))

    def paintEvent(self, e):
        qp = QPainter(self)
        qp.setBrush(QColor(0,0, 0, 255))
        for i in range(5):
            qp.drawRect(0, self.stf_top + self.line_spacing * i, self.width(), self.line_width)
        for i in range(5):
            qp.drawRect(0, self.stf_top + self.line_spacing * (i+4) + self.hl_spacing, self.width(), self.line_width)
        if self.is_h:
            self.draw_note(qp, 'h', self.level / 2, self.pos_x)
        else:
            self.draw_note(qp, 'l', self.level / 2, self.pos_x)

        qp.setFont(QFont("", 60))
        qp.setPen(QColor(0, 0, 0, 255))
        if self.is_show:
            qp.drawText(420, 400, self.cur_s_name + " " + str(self.cur_level_name) + " " + self.cur_n_name)

    def keyPressEvent(self, e):
        if e.key() == Qt.Key_N:
            self.level = self.level + randint(-3, 3) if randint(0, 7) else randint(-10, 10)
            if self.level > 12:
                self.level = 12
            if self.level < -12:
                self.level = -12
            self.pos_x = int(random()*self.request_width)
            self.is_h = randint(0, 6) if self.is_h else not randint(0, 6)
            if self.is_h:
                self.cur_s_name = self.s_name[(self.level + 6) % 7]
                self.cur_n_name = self.n_name[(self.level + 6) % 7]
                self.cur_level_name = (self.level + 6) % 7 + 1
            else:
                self.cur_s_name = self.s_name[(self.level + 1) % 7]
                self.cur_n_name = self.n_name[(self.level + 1) % 7]
                self.cur_level_name = (self.level + 1) % 7 + 1
        if e.key() == Qt.Key_S:
            self.is_show = True
        if e.key() == Qt.Key_X:
            self.is_show = False
        self.update()




if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = StaffMainWindow()
    sys.exit(app.exec_())

Useful Links

• Articles: https://python-commandments.org/
• PyQt: https://pythonpyqt.com/
• Tutorial: https://pythonprogramminglanguage.com/