基于pyQt5的界面动态绘图（提供实时动态风画图）
本文提供了一个基于pyqt5的界面绘图，主要原理就是设计一个类，继承于QWidget控件，然后重写绘图事件paintEvent，在其内部实现重新绘图，利用update()函数动态更新
画图类
下面作者给出了这个类
class PaintArea(QWidget):
def __init__(self,parent = None, *args, **kwargs):
super().__init__(parent, *args, **kwargs)
self.setPalette(QPalette(QColor(240,240,240)))#设置背景颜色
self.setAutoFillBackground(True)#设置窗口自动填充背景
def paintEvent(self, event):#重写事件
self.resize(self.width(),self.width())
self.painter = QPainter()#创建绘图类
self.painter.begin(self)#开始
#在这里画图
self.painter.end()#结束
基于pyQt5的界面绘图
下面是一个基于pyqt5的画图实践，作者画了一个边缘为黑色，内部填充蓝色的园
from PyQt5.Qt import *
class PaintArea(QWidget):
def __init__(self,parent = None, *args, **kwargs):
super().__init__(parent, *args, **kwargs)
self.setPalette(QPalette(QColor(240,240,240)))#设置背景颜色
self.setAutoFillBackground(True)#设置窗口自动填充背景
def paintEvent(self, event):#重写事件
self.resize(self.width(),self.width())
self.rect_base = QRect(20,20,self.width()-40,self.width()-40)
self.painter = QPainter()#创建绘图类
self.painter.begin(self)#开始
self.painter.setBrush(QColor(100,100,255))#设置画刷用于填充
self.painter.setPen(QPen(QColor(0,0,0),10,Qt.SolidLine))#设置画笔，画边缘
self.painter.drawEllipse(self.rect_base)#画园
self.painter.end()#结束
class Window(QWidget):
def __init__(self):
super().__init__()
self.setWindowTitle("pyqt5画图类")
self.resize(500,500)
self.setup_ui()
def setup_ui(self):
#子控件加这里
self.area = PaintArea(self)#添加画图控件
self.area.resize(300,300)#设置大小
self.area.move(100,100)#设置位置
if __name__ == "__main__":
import sys
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())
拓展实践（实时动态风）
利用update()函数，实现动态绘制风向风速，为了方便动态布局，里面的所有长度信息均是动态的，随绘图尺寸改变而改变。
#好处在于可以把子控件放在一起，且重复使用，只需调用这个包就好了
from PyQt5.Qt import *
import math
import random
class PaintArea(QWidget):#画图类
def __init__(self,parent = None, *args, **kwargs):
super().__init__(parent, *args, **kwargs)
self.setPalette(QPalette(QColor(240,240,240)))#设置背景颜色
self.setAutoFillBackground(True)#设置窗口自动填充背景
self.runway_direction = 45#跑道角度
self.wind_direction = 90#初始风向
self.wind_speed = 0#初始风速
def paintEvent(self, event):#重写绘图事件
self.rect_base = QRect(20,20,self.width()-40,self.width()-40)#设置了画图的区域
self.painter_base = QPainter()#底图绘图类
self.painter_base.begin(self)
#底图
self.painter_base.setBrush(QColor(100,100,255))
self.painter_base.setPen(QPen(QColor(255,255,255),10,Qt.SolidLine))
self.painter_base.drawEllipse(self.rect_base)
self.painter_base.end()
#计算跑道起始结束坐标
self.fromX_runway_direction, self.fromY_runway_direction, self.toX_runway_direction, self.toY_runway_direction = self.calculatePoint(self.runway_direction)
self.painter = QPainter()#画图类
self.painter.begin(self)
#画刻度盘
self.drowLines(self.fromX_runway_direction, self.fromY_runway_direction, self.toX_runway_direction, self.toY_runway_direction,width = self.width()/5)#画跑道
self.drowLines(20, int(self.height()/2), self.width()-20,int(self.height()/2), width=2, color=QColor(145,146,171))#画水平线
self.drowLines(int(self.width()/2),20, int(self.width()/2),self.height() - 20, width=2, color=QColor(145,146,171))#画垂直线
self.drawEllipses(self.rect_base)#画边界园
self.drawTexts(QRect(5,0,self.width(),30),"0°",fontsize=int(self.width()/15))#画0°
self.drawTexts(QRect(5,self.height()-30,self.width(),30),"180°",fontsize=int(self.width()/15))#画180°
self.drawTexts(QRect(0,0,70,self.height()),"270°",fontsize=int(self.width()/15))#画270°
self.drawTexts(QRect(self.width()-40,0,40,self.height()),"90°",fontsize=int(self.width()/15))#画90°
self.drawTexts(self.rect_base, self.wind_speed, fontsize= int(self.width()/3))#画风速
#计算风向箭头四个点坐标
po1_x, po1_y, a, b = self.calculatePoint1(self.wind_direction-7)
po3_x, po3_y, a, b = self.calculatePoint1(self.wind_direction+7)
a, b, po4_x, po4_y = self.calculatePoint(self.wind_direction)
po1 = QPoint(po1_x, po1_y)
po2 = QPoint(int(self.width()/2), int(self.height()/2))
po3 = QPoint(po3_x, po3_y)
po4 = QPoint(po4_x, po4_y)
points = [po1,po2,po3,po4]
#画风向箭头
self.drawPolygons(points)
self.painter.end()#结束
#从外部获取风向
def setWindDirection(self, wind_direction):
self.wind_direction = wind_direction
#从外部获取风速
def setWindSpeed(self, wind_speed):
self.wind_speed = wind_speed
#画线
def drowLines(self, fromX, fromY, toX, toY, width = 10, color = QColor(91,91,170)):
pen = QPen(color,width,Qt.SolidLine)
self.painter.setPen(pen)
self.painter.drawLine(fromX, fromY, toX, toY)
#画圆
def drawEllipses(self, rect, width = 10, color = QColor(180,180,220)):
pen = QPen(color,width, Qt.DashLine)
self.painter.setPen(pen)
self.painter.drawEllipse(rect)
#画字
def drawTexts(self, rect, ws, fontsize = 100):
self.painter.setPen(QColor(0,255,0))
self.painter.setFont(QFont('Arial', fontsize))
self.painter.drawText(rect, Qt.AlignCenter, str(ws))
#画区域
def drawPolygons(self,points):
self.painter.setPen(QColor(255,172,39))
self.painter.setBrush(QColor(211,211,39))
self.painter.drawPolygon(QPolygon(points), Qt.WindingFill)
#计算坐标
def calculatePoint(self,angle_old):
angle = math.radians(angle_old)
toX = int(((self.width()-40)/2 - self.width()/9) * math.sin(angle) +self.width()/2)
toY = int(((self.height()-40)/2 - self.height()/9) * math.cos(angle) * -1 +self.height()/2)
fromX = self.width() - toX
fromY = self.height() - toY
return fromX, fromY, toX, toY
#计算坐标
def calculatePoint1(self,angle_old):
angle = math.radians(angle_old)
toX = int((self.width()/2 - self.width()/20) * math.sin(angle) +self.width()/2)
toY = int((self.height()/2 - self.height()/20) * math.cos(angle) * -1 +self.height()/2)
fromX = self.width() - toX
fromY = self.height() - toY
return toX, toY,fromX, fromY
#窗口类
class Window(QWidget):
def __init__(self):
super().__init__()
self.setWindowTitle("pyqt5画图类")
self.resize(500,500)
self.setup_ui()
#定时器
self.timer = QTimer(self)
self.timer.timeout.connect(self.get_wind)
self.timer.start(3000)
def setup_ui(self):
#子控件加这里
self.area = PaintArea(self)
self.area.resize(300,300)
self.area.move(100,100)
#随机产生风向风速，动态绘图
def get_wind(self):
wind_direction = random.randint(0,359)
wind_speed = random.randint(0,18)
self.area.setWindDirection(wind_direction)
self.area.setWindSpeed(wind_speed)
self.area.update()#动态刷新风
if __name__ == "__main__":
import sys
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())