Question

我正在使用Enthought的Traits在python中开发GUI。我一直得到一个“运行错误：cmp中超出了最大递归深度”如果我翻转我的MainWindow类中使用“Item”标签的顺序，代码执行正常。我似乎无法找到有关为什么会发生这种情况的任何文档。这似乎与Chaco情节有关。以下是我的测试代码。

from chaco.api import ArrayPlotData, Plot
from traits.api import HasTraits, Instance, String, Float, Enum, Button, Str
from traitsui.api import Handler, View, Item, Group, HSplit, NoButtons, VGroup, VGrid
from pyface.api import GUI
from threading import Thread
from time import sleep
from enthought.enable.component_editor import ComponentEditor
from scipy import rand, indices, exp, sqrt, sum
import numpy as np
from PIL import Image
import matplotlib.image as mpimg
from enthought.chaco.api import gray
from enthought.savage.traits.ui.svg_button import SVGButton


class User_Input_Panel(HasTraits):

    User = Str(name='User', label="User Name")
    Sample_Name = Str(name='Sample_Name',label="Sample Name")
    Path = Str(name='Path', label="Save Location", style = 'readonly')

    #I use this to create a folder icon on the button
    #~ Save_Folder_Button = SVGButton(label='Choose save Location', \
                            #~ filename=Folder-drag-accept.svg', \
                            #~ width=28, \
                            #~ height=28 \
                           #~ )



    #~ #Create the User Information panel
    User_Information_Panel = View(VGroup(
                                    VGrid(
                                          Item('User'), 
                                          Item('Sample_Name'), 
                                          Item('Path', width=.700, visible_when = 'Save_Visible == True'),                              
                                          #Item('Save_Folder_Button', show_label=False),
                                          ),
                                    show_border=True, label="User Information"
                                    ))

    def _Save_Folder_Button_fired(self, event):

        print("Pushed the Save Folder")
        #self.file, self.dir = wxOpenFile(multi=False)
        #fdir = GUI_tools.wxOpenFile()
        #fdir = GUI_tools.wxSavePath()


#I'm planning on setting up threading later
class MainWindowHandler(Handler):

    def close(self, info, is_OK):
        #~ if (info.object.user_input.acquisition_thread and \
            #~ info.object.user_input.acquisition_thread.isAlive()):
            #~ info.object.user_input.acquisition_thread.wants_abort = True
            #~ while info.object.user_input.acquisition_thread.isAlive():
                #~ sleep(0.1)
            #~ GUI.process_events()
        return True


class MainWindow(HasTraits):

    plot = Instance(Plot)
    plotdata = Instance(ArrayPlotData, ())
    user_input = Instance(User_Input_Panel, ())


    def _user_input_default(self):
        return User_Input_Panel(plotdata = self.plotdata)

    Save_Folder_Button = SVGButton(label='Choose save Location', \
                            filename='C:\Python27\Examples\Mill_GUI\Tescan_BatchScan\Folder-drag-accept.svg', \
                            width=28, \
                            height=28 \
                           )

    def _plot_default(self):
        self.plotdata = ArrayPlotData(imagedata=np.zeros((100,100)))
        plot = Plot(self.plotdata)
        plot.img_plot('imagedata')
        self.plot = plot
        return plot

    # If I flip the "Item('user_input'" with "Item('plot') the code will run...
    view = View(VGroup(Item('user_input', style = 'custom', show_label = False), 
                       Item('plot', editor = ComponentEditor(), dock = 'vertical'),
                       show_labels = False),
                       resizable = True, handler = MainWindowHandler(),
                       buttons = NoButtons)

if __name__ == '__main__':
    MainWindow().configure_traits()

有人知道为什么你会用这段代码得到递归错误？我必须在user_input面板下方显示图表，以便用户可以看到他们正在收集的实时数据。

干杯， Shivels

Answer 1

您需要从_plot_default方法中删除以下行： self.plot = plot 为了在traits中发生这种情况，你只需要返回该绘图对象，并且将通过Traits完成对self.plot的赋值。发生递归错误是因为您尝试访问尝试设置它的方法内的对象的plot属性。

Python Traits GUI递归深度

1 个答案: