绘图API: 绘制各种图形 的案例
弧形
圆形
椭圆
矩形（正方形）
多边形

import math
import sys
from PyQt5.QtCore import Qt, QRegExp, QDir, QRect, QPoint
from PyQt5.QtGui import QIcon, QFont, QPalette, QPixmap, QIntValidator, QDoubleValidator, QRegExpValidator, QPainter, \
    QColor, QPen, QPolygon, QImage
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QToolTip, QHBoxLayout, QMainWindow, QLabel, QVBoxLayout, \
    QDialog, QLineEdit, QGridLayout, QFormLayout, QTextEdit, QRadioButton, QCheckBox, QSlider, QSpinBox, QMessageBox, \
    QInputDialog, QFontDialog, QColorDialog, QFileDialog

'''
绘图API: 绘制各种图形 的案例
弧形
圆形
椭圆
矩形（正方形）
多边形

'''


class drawDemo(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        # 设置定位和左上角坐标
        self.setGeometry(300, 300, 400, 520)
        # 设置窗口标题
        self.setWindowTitle('在窗口上绘制不同的各种图形 的演示')
        # 设置窗口图标
        # self.setWindowIcon(QIcon('../web.ico'))

    def paintEvent(self,event):
        qp = QPainter(self)
        qp.begin(self)
        print("- - -")
        qp.setPen(Qt.blue)
        # 画弧线
        rect = QRect(0,10,100,100)
        # alen : 1个alen 等于 1/16度 45*16
        qp.drawArc(rect,0,50*16)
        #通过弧绘制圆形
        qp.setPen(Qt.red)
        qp.drawArc(120,10,100,100,0,360*16)
        # 绘制带弦的弧
        qp.drawChord(10,120,100,100,12,130*16)
        # 绘制扇形
        qp.drawPie(10,240,100,100,12,130*16)
        # 绘制椭圆
        qp.drawEllipse(120,120,150,100)
        # 绘制五边形
        point1 = QPoint(140,380)
        point2 = QPoint(270,380)
        point3 = QPoint(290,510)
        point4 = QPoint(290,580)
        point5 = QPoint(200,530)
        polygon = QPolygon([point1,point2,point3,point4,point5])
        qp.drawPolygon(polygon)

        # 绘制图像
        image = QImage('../web.ico')
        rect = QRect(10,400,image.width()*3,image.height()*3)
        qp.drawImage(rect,image)



        qp.end()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    # 设置应用图标
    app.setWindowIcon(QIcon('../web.ico'))
    w = drawDemo()
    w.show()
    sys.exit(app.exec_())