Qt Designer与pglive集成实时绘图报错求助

已通过pglive实现实时正弦曲线和Arduino串口数据绘图，现在想集成Qt Designer制作的GUI，将ui中的plot1提升为LivePlotWidget后，运行代码出现以下报错：

Traceback (most recent call last):
  File "C:\Users\New Wyss User\AppData\Roaming\Python\Python311\site-packages\pglive\sources\live_plot.py", line 134, in <lambda>
    plot.slot_roll_tick = lambda data_connector, tick: plot.plot_widget.slot_roll_tick(data_connector, tick)
                                                       ^^^^^^^^^^^^^^^^
AttributeError: plot_widget
Traceback (most recent call last):
  File "C:\Users\New Wyss User\AppData\Roaming\Python\Python311\site-packages\pglive\sources\live_plot.py", line 121, in <lambda>
    plot.slot_new_data = lambda y, x, kwargs: plot.setData(x, y, **kwargs)
                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: setData(self, key: int, value: Any): argument 1 has unexpected type 'numpy.ndarray'

使用的代码如下：

import sys
from math import sin
from threading import Thread
from time import sleep
from PyQt5.QtWidgets import QApplication
from PyQt5 import QtWidgets, QtCore, uic
from pglive.sources.data_connector import DataConnector
from pglive.sources.live_plot import LiveLinePlot
from pglive.sources.live_plot_widget import LivePlotWidget
import serial

arduino = serial.Serial(port='COM17', baudrate=9600, timeout=.1) 

app = QApplication(sys.argv)
running = True

ui = uic.loadUi('test.ui')

plot_widget = ui.plot1 # LivePlotWidget(title="Line Plot @ 100Hz")
# plot_curve = LiveLinePlot()
# plot_widget.addItem(plot_curve)
# DataConnector holding 600 points and plots @ 100Hz
data_connector = DataConnector(ui.plot1, max_points=600, update_rate=100)
# data_connector = DataConnector(plot_curve, max_points=600, update_rate=100)

def sin_wave_generator(connector):
    """Sine wave generator"""
    x = 0
    while running:
        x += 1
        data = arduino.readline().decode("utf-8") # retrieve serial data from feather
        values = data.split(",") # split at commas
        data_point = float(values[0])
        # Callback to plot new data point
        connector.cb_append_data_point(data_point, x)
        sleep(0.01)

plot_widget.show()
Thread(target=sin_wave_generator, args=(data_connector,)).start()
app.exec()
running = False

核心问题 #

DataConnector的初始化参数需要的是**LivePlot子类对象（比如LiveLinePlot）**，而不是LivePlotWidget容器。直接把ui.plot1（LivePlotWidget）传给DataConnector，会导致内部调用曲线相关方法时出错。

修正步骤 #

1. 恢复创建LiveLinePlot曲线对象的代码，并将其添加到LivePlotWidget中
2. 将DataConnector关联到LiveLinePlot对象，而非LivePlotWidget
3. 增加串口数据的有效性判断，避免空数据或格式错误导致崩溃

修正后的代码 #

import sys
from threading import Thread
from time import sleep
from PyQt5.QtWidgets import QApplication
from PyQt5 import uic
from pglive.sources.data_connector import DataConnector
from pglive.sources.live_plot import LiveLinePlot
import serial

arduino = serial.Serial(port='COM17', baudrate=9600, timeout=.1) 

app = QApplication(sys.argv)
running = True

ui = uic.loadUi('test.ui')

# 获取Qt Designer中提升的LivePlotWidget
plot_widget = ui.plot1
# 创建LiveLinePlot曲线并添加到widget中
plot_curve = LiveLinePlot()
plot_widget.addItem(plot_curve)
# 将DataConnector关联到LiveLinePlot对象
data_connector = DataConnector(plot_curve, max_points=600, update_rate=100)

def serial_data_generator(connector):
    x = 0
    while running:
        x += 1
        data = arduino.readline().decode("utf-8").strip() # 去除首尾空白字符
        if not data:
            sleep(0.01)
            continue
        try:
            values = data.split(",")
            data_point = float(values[0])
            connector.cb_append_data_point(data_point, x)
        except (IndexError, ValueError):
            # 处理数据格式错误的情况
            print(f"无效数据: {data}")
        sleep(0.01)

# 显示整个UI窗口（而非单独的plot_widget）
ui.show()
Thread(target=serial_data_generator, args=(data_connector,)).start()
app.exec()
running = False
arduino.close() # 关闭串口连接

额外注意事项 #

• 确保Qt Designer中plot1的提升设置正确：类名是LivePlotWidget，头文件是pglive.sources.live_plot_widget
• 串口数据读取时加入异常捕获，避免Arduino发送空数据或格式错误导致程序崩溃
• 程序退出时记得关闭串口连接，释放资源

内容的提问来源于stack exchange，提问作者Sfrow