在你的代碼中有很多所以我只列出它們：
如果您打算使用 FigureCanvasQTAgg，那么您不應該再使用 pyplot。
“mplWidget”是一個唯一任務是重繪畫布的類，那么它必須是一個 QWidget 嗎？。
例如，如果您要比較布爾值，請不要使用“is”，我if self.plotSnap is False:也if not self.plotSnap:認為認為“plotSnap”為 False 是不合邏輯的，如果您想禁用，則設置一個不可能的值，例如 0 或負數。
考慮到上面我已經讓 MplWidget 繼承自 FigureCanvasQTAgg，我已經消除了 pyplot 的使用：
import numpy as np
from PyQt5 import QtCore, QtGui, QtWidgets
from matplotlib.backends.backend_qt5agg import (
FigureCanvasQTAgg,
NavigationToolbar2QT as NavigationToolbar,
)
from matplotlib.figure import Figure
class MplWidget(FigureCanvasQTAgg):
def __init__(self, parent=None):
fig = Figure()
super(MplWidget, self).__init__(fig)
self.setParent(parent)
# Set default colors array
self.defaultColors = np.array(
[
[0, 0.4470, 0.7410],
[0.8500, 0.3250, 0.0980],
[0.9290, 0.6940, 0.1250],
[0.4660, 0.6740, 0.1880],
[0.6350, 0.0780, 0.1840],
[0.4940, 0.1840, 0.5560],
[0.3010, 0.7450, 0.9330],
]
)
# Create a figure with axes
self.ax = self.figure.add_subplot(111)
# Form the plot and shading
self.bottomLeftX = 0
self.bottomLeftY = 0
self.topRightX = 0
self.topRightY = 0
self.x = np.array(
[
self.bottomLeftX,
self.bottomLeftX,
self.topRightX,
self.topRightX,
self.bottomLeftX,
]
)
self.y = np.array(
[
self.bottomLeftY,
self.topRightY,
self.topRightY,
self.bottomLeftY,
self.bottomLeftY,
]
)
(self.myPlot,) = self.ax.plot(self.x, self.y, color=self.defaultColors[0, :])
self.aspan = self.ax.axvspan(
self.bottomLeftX, self.topRightX, color=self.defaultColors[0, :], alpha=0
)
self.ax.set_xlim((-100, 100))
self.ax.set_ylim((-100, 100))
# Set moving flag false (determines if mouse is being clicked and dragged inside plot). Set graph snap
self.moving = False
self.plotSnap = 5
# Set up connectivity
self.cid1 = self.mpl_connect("button_press_event", self.onclick)
self.cid2 = self.mpl_connect("button_release_event", self.onrelease)
self.cid3 = self.mpl_connect("motion_notify_event", self.onmotion)
def setSnapBase(self, base):
return lambda value: int(base * round(float(value) / base))
def onclick(self, event):
if self.plotSnap <= 0:
self.bottomLeftX = event.xdata
self.bottomLeftY = event.ydata
else:
self.calculateSnapCoordinates = self.setSnapBase(self.plotSnap)
self.bottomLeftX = self.calculateSnapCoordinates(event.xdata)
self.bottomLeftY = self.calculateSnapCoordinates(event.ydata)
try:
self.aspan.remove()
except:
pass
self.moving = True
def onrelease(self, event):
if self.plotSnap <= 0:
self.topRightX = event.xdata
self.topRightY = event.ydata
else:
try:
calculateSnapCoordinates = self.setSnapBase(self.plotSnap)
self.topRightX = calculateSnapCoordinates(event.xdata)
self.topRightY = calculateSnapCoordinates(event.ydata)
except:
pass
self.x = np.array(
[
self.bottomLeftX,
self.bottomLeftX,
self.topRightX,
self.topRightX,
self.bottomLeftX,
]
)
self.y = np.array(
[
self.bottomLeftY,
self.topRightY,
self.topRightY,
self.bottomLeftY,
self.bottomLeftY,
]
)
self.myPlot.set_xdata(self.x)
self.myPlot.set_ydata(self.y)
# ax.fill_between(x, y, color=defaultColors[0, :], alpha=.25)
ylimDiff = self.ax.get_ylim()[1] - self.ax.get_ylim()[0]
self.aspan = self.ax.axvspan(
self.bottomLeftX,
self.topRightX,
(self.bottomLeftY - self.ax.get_ylim()[0]) / ylimDiff,
(self.topRightY - self.ax.get_ylim()[0]) / ylimDiff,
color=self.defaultColors[0, :],
alpha=0.25,
)
self.moving = False
self.draw()
def onmotion(self, event):
if not self.moving:
return
if event.inaxes is None:
return
if event.button != 1:
return
if self.plotSnap <= 0:
self.topRightX = event.xdata
self.topRightY = event.ydata
else:
self.calculateSnapCoordinates = self.setSnapBase(self.plotSnap)
self.topRightX = self.calculateSnapCoordinates(event.xdata)
self.topRightY = self.calculateSnapCoordinates(event.ydata)
self.x = np.array(
[
self.bottomLeftX,
self.bottomLeftX,
self.topRightX,
self.topRightX,
self.bottomLeftX,
]
)
self.y = np.array(
[
self.bottomLeftY,
self.topRightY,
self.topRightY,
self.bottomLeftY,
self.bottomLeftY,
]
)
self.myPlot.set_xdata(self.x)
self.myPlot.set_ydata(self.y)
self.draw()
class TopLevelWindow(QtWidgets.QMainWindow):
def __init__(self):
super().__init__()
self.canvas = MplWidget()
self.setCentralWidget(self.canvas)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
w = TopLevelWindow()
w.show()
sys.exit(app.exec_())
