使用日志功能个性化Matplotlib工具栏

Question

我有一个带有工具栏的简单绘图。我添加了一个小部件，但是无法找到方法告诉这个按钮将主绘图从普通视图切换到日志视图。我不知道如何从这个按钮事件（pickerToggled（self，checked））访问给绘图的数据。在

这是我目前掌握的密码。在

import sys, os, math
from PyQt4.QtCore import *
from PyQt4.QtGui import *

import matplotlib
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg
from matplotlib.figure import Figure

class NavigationToolbar( NavigationToolbar2QTAgg ):

    picked=pyqtSignal(int,name='picked')

    def __init__(self, canvas, parent ):
        NavigationToolbar2QTAgg.__init__(self,canvas,parent)
        self.clearButtons=[]
        # Search through existing buttons
        # next use for placement of custom button
        next=None
        for c in self.findChildren(QToolButton):
            if next is None:
                next=c
            # Don't want to see subplots and customize
            if str(c.text()) in ('Subplots','Customize'):
                c.defaultAction().setVisible(False)
                continue
            # Need to keep track of pan and zoom buttons
            # Also grab toggled event to clear checked status of picker button
            if str(c.text()) in ('Pan','Zoom'):
                c.toggled.connect(self.clearPicker)
                self.clearButtons.append(c)
                next=None

        # create custom button
        pm=QPixmap(32,32)
        pm.fill(QApplication.palette().color(QPalette.Normal,QPalette.Button))
        painter=QPainter(pm)
        painter.fillRect(6,6,20,20,Qt.red)
        painter.fillRect(15,3,3,26,Qt.blue)
        painter.fillRect(3,15,26,3,Qt.blue)
        painter.end()
        icon=QIcon(pm)
        picker=QAction("Pick",self)
        picker.setIcon(icon)
        picker.setCheckable(True)
        picker.setToolTip("Pick data point")
        self.picker = picker
        button=QToolButton(self)
        button.setDefaultAction(self.picker)

        # Add it to the toolbar, and connect up event
        self.insertWidget(next.defaultAction(),button)
        picker.toggled.connect(self.pickerToggled)

        # Grab the picked event from the canvas
        canvas.mpl_connect('pick_event',self.canvasPicked)

    def clearPicker( self, checked ):
        if checked:
            self.picker.setChecked(False)

    def pickerToggled( self, checked ):
        if checked:
            #### code to add to display plot in logscale


            for c in self.clearButtons:
                c.defaultAction().setChecked(False)
            self.set_message('Reject/use observation')

        else: # linear plot
           #### code to come back to linear scale plot

    def canvasPicked( self, event ):
        if self.picker.isChecked():
            self.picked.emit(event.ind)

class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        QMainWindow.__init__(self, parent)
        self.x=[i*0.1 for i in range(30)]
        self.y=[math.sin(x) for x in self.x]
        self.picked=[]
        self.setWindowTitle('Custom toolbar')

        self.frame = QWidget()

        self.fig = Figure((4.0, 4.0))
        self.canvas = FigureCanvasQTAgg(self.fig)
        self.canvas.setParent(self.frame)

        self.axes = self.fig.add_subplot(111)

        # Create the navigation toolbar, tied to the canvas
        # and link the clicked event
        self.toolbar = NavigationToolbar(self.canvas, self.frame)
        self.toolbar.picked.connect(self.addPoint)

        vbox = QVBoxLayout()
        vbox.addWidget(self.canvas)
        vbox.addWidget(self.toolbar)
        self.frame.setLayout(vbox)
        self.setCentralWidget(self.frame)
        self.draw()

    def draw(self):
        while self.axes.lines:
            self.axes.lines[0].remove()
        self.axes.plot(self.x,self.y,'b+',picker=5)
        xp=[self.x[i] for i in self.picked] 
        yp=[self.y[i] for i in self.picked] 
        self.axes.plot(xp,yp,'rs')
#        self.axes.set_xscale('log')
        self.canvas.draw()

    def addPoint(self,index):
        if index in self.picked:
            self.picked.remove(index)
        else:
            self.picked.append(index)
        self.draw()

if __name__ == "__main__":
    app = QApplication(sys.argv)
    form = MainWindow()
    form.show()
    app.exec_()

Answer 1

这是设计上的一个选择，但这里有一个我可能会做的概要，这可能不一定是最好的，但会起作用。您已经有了一个draw函数，它可以根据某些参数重新绘制绘图，所以对于linear/log，我会在您的MainWindow中添加一个表示日志切换的属性。在

在主窗口中

# In the __init__ before the call to self.draw
self.islog = False

# Connect the new signal (defined below)
self.toolbar.picked.connect(self.addPoint)
self.toolbar.logtog.connect(self.logtoggle) # new

然后在self.draw中，我将把绘图代码放入一个处理线性或对数的if语句中。在

^{pr2}$

并构造切换设置的新方法：

def logtoggle(self, checked):
    self.islog = checked
    self.draw()

在导航工具栏中

至于从工具栏返回信号，您已经发送了一个自定义信号，所以您已经有了它的公式。比如：

picked=pyqtSignal(int,name='picked')
logtog = pyqtSignal(bool) # new signal

然后添加一个自定义按钮，就像你做的其他，使它可以检查一样。。。在

# New button stuff
pm=QPixmap(32,32)
pm.fill(QColor(0,0,255)) # Uniform fill just for demonstration
ic = QIcon(pm)
ac = self.addAction(ic, "Toggle Log") # This will end up on the far right - you can place it wherever you want
ac.setCheckable(True)
ac.toggled.connect(self.logtoggle)

当然，编写toolbar方法来发出信号：

def logtoggle(self, checked):
    self.logtog.emit(checked)

我在你提供的代码中添加了以上所有的内容，它运行得很好。你已经有了所有的原料，我只是添加了一些类似的东西。在