pyqtgraph 中的多个叠加图（无法绑定轴）

Question

我的图表有点问题。我可以同时绘制两条曲线，但第二条曲线似乎也绑定到左轴，有谁知道我是否可以用第二条曲线绘制右轴比例？ 这是一个有效的简短示例：

from PyQt4 import QtCore, QtGui
import pyqtgraph as pg
import random

class MainWindow(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.central_widget = QtGui.QStackedWidget()
        self.setCentralWidget(self.central_widget)
        self.login_widget = LoginWidget(self)
        self.login_widget.button.clicked.connect(self.plotter)
        self.central_widget.addWidget(self.login_widget)

    def plotter(self):
        self.data =[0]
        self.data2 = [0]
        self.curve = self.login_widget.plot.getPlotItem().plot()
        self.curve2 =self.login_widget.plot.getPlotItem().plot()
        self.timer = QtCore.QTimer()
        self.timer.timeout.connect(self.updater)
        self.timer.start(0)

    def updater(self):

        self.data.append(self.data[-1]+0.2*(0.5-random.random()) )
        self.curve.setData(self.data, pen=pg.mkPen('b', width=1))
        self.data2.append(self.data2[-1]+0.2*(0.5-random.random()) )
        self.curve2.setData(self.data2, pen=pg.mkPen('r', width=1))

class LoginWidget(QtGui.QWidget):
    def __init__(self, parent=None):
        super(LoginWidget, self).__init__(parent)
        layout = QtGui.QVBoxLayout()
        pg.setConfigOption('background', 'w')
        pg.setConfigOption('foreground', 'k')
        self.button = QtGui.QPushButton('Start Plotting')
        layout.addWidget(self.button)
        self.plot = pg.PlotWidget(title='Force and Extension vs. Time')
        #self.plot.showGrid(x=True,y=True)
        self.plot.showAxis('right')
        p2 = pg.ViewBox()
        self.plot.scene().addItem(p2)
        p2.setXLink(self.plot)
        ax2 = self.plot.getAxis('right').linkToView(p2)
        ax = self.plot.getAxis('bottom')
        ax3 = self.plot.getAxis('right')
        ax3.setLabel('Extension', units='in.')
        ax.setLabel('Time', units='s')
        ay = self.plot.getAxis('left')
        ay.setLabel('Force', units='lbf')
        layout.addWidget(self.plot)
        self.setLayout(layout)
    def pg_clear(self):
        self.plot.clear()

if __name__ == '__main__':
    app = QtGui.QApplication([])
    window = MainWindow()
    window.show()
    app.exec_()

Answer 1

基于link 中显示的示例，我实现了以下解决方案，我为每个轴的标签添加了必要的颜色以轻松识别数据，我还实现了 updateViews() 函数，以便当我改变了屏幕的大小就可以正常显示了。

注意：我已经修改了生成数据的函数，以便观察到变化。

class MainWindow(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.central_widget = QtGui.QStackedWidget()
        self.setCentralWidget(self.central_widget)
        self.login_widget = LoginWidget(self)
        self.login_widget.button.clicked.connect(self.plotter)
        self.central_widget.addWidget(self.login_widget)

        self.curve = self.login_widget.it1
        self.curve2 =self.login_widget.it2

    def plotter(self):
        self.data =[0]
        self.data2 = [0]
        self.timer = QtCore.QTimer()
        self.timer.timeout.connect(self.updater)
        self.timer.start(0)

    def updater(self):
        self.data.append(self.data[-1]+10*(0.5-random.random())) 
        self.curve.setData(self.data, pen=pg.mkPen('b', width=1))
        self.data2.append(self.data2[-1]+0.1*(0.5-random.random()))
        self.curve2.setData(self.data2, pen=pg.mkPen('r', width=1))

class LoginWidget(QtGui.QWidget):
    def __init__(self, parent=None):
        super(LoginWidget, self).__init__(parent)
        layout = QtGui.QVBoxLayout()
        pg.setConfigOption('background', 'w')
        pg.setConfigOption('foreground', 'k')
        self.button = QtGui.QPushButton('Start Plotting')
        layout.addWidget(self.button)
        self.plot = pg.PlotWidget(title='Force and Extension vs. Time')
        layout.addWidget(self.plot)
        self.setLayout(layout)

        p1 = self.plot.plotItem
        p2 = pg.ViewBox()
        p1.showAxis('right')
        p1.scene().addItem(p2)
        p1.getAxis('right').linkToView(p2)
        p2.setXLink(p1)

        self.plot.getAxis('bottom').setLabel('Time', units='s')
        self.plot.getAxis('left').setLabel('Force', units='lbf', color="#0000ff")
        p1.getAxis('right').setLabel('Extension', units='in.', color="#ff0000")

        def updateViews():
            p2.setGeometry(p1.vb.sceneBoundingRect())
            p2.linkedViewChanged(p1.vb, p2.XAxis)

        updateViews()
        p1.vb.sigResized.connect(updateViews)

        self.it1 = p1.plot()
        self.it2 = pg.PlotCurveItem()
        p2.addItem(self.it2)