如何在PyQt4中用FigureCanvas创建多个独立弹出式图表？

Got it, let's tackle this problem. You want to replace plt.show() with FigureCanvas to generate 3 independent chart windows (instead of embedding them into one window), while keeping the original button and progress bar functionality. Here's a complete working solution:

Modified Full Code #

import sys
from PyQt4.QtGui import *
from PyQt4.QtCore import *
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure
import pandas as pd

class ChartWindow(QMainWindow):
    def __init__(self, dataframe, parent=None):
        super(ChartWindow, self).__init__(parent)
        self.setWindowTitle("Matplotlib Chart")
        # Create matplotlib figure and Qt canvas widget
        self.figure = Figure()
        self.canvas = FigureCanvas(self.figure)
        self.setCentralWidget(self.canvas)
        # Plot the dataframe on the figure
        ax = self.figure.add_subplot(111)
        dataframe.plot(grid=1, ax=ax)
        # Refresh the canvas to render the plot
        self.canvas.draw()

class App(QMainWindow):
    def __init__(self):
        super(App, self).__init__()
        self.setGeometry(500, 300, 820, 350)
        self.setWindowTitle("Program")
        # Buttons
        btnposx = 30
        btnposy = 50
        self.btn4 = QPushButton('Load', self)
        self.btn4.move(btnposx, btnposy + 220)
        self.btn4.released.connect(self.thread)
        # ProgressBar
        self.pb = QProgressBar(self)
        self.pb.move(btnposx + 150, btnposy + 220)
        self.pb.resize(470, 27)
        self.show()

    @pyqtSlot(float)
    def load(self, val):
        self.pb.setValue(val)

    @pyqtSlot(object)
    def plot(self, pq):
        # Create a new independent chart window for each plot signal
        chart_win = ChartWindow(pq)
        chart_win.show()

    def thread(self):
        self.thread_ = Thread()
        self.thread_.pb_signal.connect(self.load, Qt.QueuedConnection)
        self.thread_.plot_signal.connect(self.plot, Qt.QueuedConnection)
        self.thread_.start()

class Thread(QThread):
    pb_signal = pyqtSignal(float)
    plot_signal = pyqtSignal(object)
    def __init__(self, *args, **kwargs):
        QThread.__init__(self, *args, **kwargs)
    def __del__(self):
        self.wait()

    @pyqtSlot()
    def run(self):
        val = 0
        self.pb_signal.emit(20)
        l = range(50000000)
        for i in l:
            val += 1
        self.pb_signal.emit(60)
        self.pb_signal.emit(100)
        pq = pd.DataFrame(data = {'col1':[1,2,3,4,5,6], 'col2':[6,5,4,3,2,1]})
        self.plot_signal.emit(pq)
        self.plot_signal.emit(pq)
        self.plot_signal.emit(pq)
        return

if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = App()
    ex.show()
    sys.exit(app.exec_())

Key Changes Explained #

• Added ChartWindow Class: This is a standalone QMainWindow subclass—each instance acts as an independent top-level window. Inside it, we create a matplotlib Figure (the plot container) and a FigureCanvas (the PyQt widget that renders the figure), then set the canvas as the window's central widget.
• Updated plot Slot: Instead of relying on plt.show(), we now spawn a new ChartWindow for every incoming plot_signal and call show() on it. This replicates the original behavior of 3 separate chart windows, but uses PyQt's native window system instead of matplotlib's pyplot wrapper.
• Removed matplotlib.pyplot Import: We don't need plt anymore because we're using matplotlib's object-oriented API directly with Figure and FigureCanvas, which integrates cleaner with PyQt.

This solution preserves all your original functionality (button trigger, progress bar updates, independent charts) while using FigureCanvas as requested.

内容的提问来源于stack exchange，提问作者Artur Müller Romanov