PyQT5之PyQtGraph实时数据显示

实例1：CPU使用率实时展示

from PyQt5 import QtWidgets,QtCore,QtGui
import pyqtgraph as pg
import sys
import traceback
import psutil


class MainUi(QtWidgets.QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("CPU使用率监控")
        self.main_widget = QtWidgets.QWidget()  # 创建一个主部件
        self.main_layout = QtWidgets.QGridLayout()  # 创建一个网格布局
        self.main_widget.setLayout(self.main_layout)  # 设置主部件的布局为网格
        self.setCentralWidget(self.main_widget)  # 设置窗口默认部件

        self.plot_widget = QtWidgets.QWidget()  # 实例化一个widget部件作为K线图部件
        self.plot_layout = QtWidgets.QGridLayout()  # 实例化一个网格布局层
        self.plot_widget.setLayout(self.plot_layout)  # 设置K线图部件的布局层
        self.plot_plt = pg.PlotWidget()  # 实例化一个绘图部件
        self.plot_plt.showGrid(x=True,y=True) # 显示图形网格
        self.plot_layout.addWidget(self.plot_plt)  # 添加绘图部件到K线图部件的网格布局层
        # 将上述部件添加到布局层中
        self.main_layout.addWidget(self.plot_widget, 1, 0, 3, 3)

        self.setCentralWidget(self.main_widget)
        self.plot_plt.setYRange(max=100,min=0)
        self.data_list = []
        self.timer_start()

    # 启动定时器 时间间隔秒
    def timer_start(self):
        self.timer = QtCore.QTimer(self)
        self.timer.timeout.connect(self.get_cpu_info)
        self.timer.start(1000)

    # 获取CPU使用率
    def get_cpu_info(self):
        try:
            cpu = "%0.2f" % psutil.cpu_percent(interval=1)
            self.data_list.append(float(cpu))
            print(float(cpu))
            self.plot_plt.plot().setData(self.data_list,pen='g')
        except Exception as e:
            print(traceback.print_exc())


def main():
    app = QtWidgets.QApplication(sys.argv)
    gui = MainUi()
    gui.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

实例2：气温数据实时展示

from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
import pyqtgraph as pg
import sys
from random import randint


class MainWindow(QMainWindow):

    def __init__(self):
        super().__init__()

        self.setWindowTitle('pyqtgraph作图')

        # 创建 PlotWidget 对象
        self.pw = pg.PlotWidget()

        # 设置图表标题
        self.pw.setTitle("气温趋势",
                         color='#008080',
                         size='12pt')

        # 设置上下左右的label
        self.pw.setLabel("left","气温(摄氏度)")
        self.pw.setLabel("bottom","时间")

        # 设置Y轴 刻度 范围
        self.pw.setYRange(min=-10, # 最小值
                          max=50)  # 最大值

        # 显示表格线
        self.pw.showGrid(x=True, y=True)

        # 背景色改为白色
        self.pw.setBackground('w')

        # 设置Y轴 刻度 范围
        self.pw.setYRange(min=-10, # 最小值
                          max=50)  # 最大值

        # 居中显示 PlotWidget
        self.setCentralWidget(self.pw)

        # 实时显示应该获取 PlotDataItem对象, 调用其setData方法，
        # 这样只重新plot该曲线，性能更高
        self.curve = self.pw.plot(
            pen=pg.mkPen('r', width=1)
        )

        self.i = 0
        self.x = [] # x轴的值
        self.y = [] # y轴的值

        # 启动定时器，每隔1秒通知刷新一次数据
        self.timer = QTimer()   # QtCore
        self.timer.timeout.connect(self.updateData)
        self.timer.start(1000)

    def updateData(self):
        self.i += 1
        self.x.append(self.i)
        # 创建随机温度值
        self.y.append(randint(10, 30))

        # plot data: x, y values
        self.curve.setData(self.x, self.y)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = MainWindow()
    main.show()
    app.exec_()