python 两个类之间传递消息 python 类之间传递数据

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mob64ca140e0490 2024-05-15 14:01:13

文章标签 python 两个类之间传递消息 python传递类的实例 hg 工作线程 Test 文章分类 Python 后端开发

我在将一个类实例中定义的变量传递到另一个类实例时遇到问题。我对使用类比较陌生，但据我所知，变量可以通过简单地定义为类实例的一部分(例如在下面的示例中)从一个实例传递到另一个实例。虽然我以前使用过这个模型，但我从未尝试过使用像wxPython这样的GUI框架来实现这一点。class Foo(object):

def __init__(self, var):
self.var = var
class Bar(object):
def do_something(self, var):
print var*3
if __name__ == '__main__':
f = Foo(3)
b = Bar()
b.do_something(f.var)

我遇到的问题是wxPython实例似乎是预定义的，不接受任何附加参数(允许我只向类实例传递标题、大小等内容)。

我面临的另一个问题是，我试图通过调用一个对话框窗口来深入传递变量三个类，并从对话框中调用一个单独的类来启动一个工作线程。

所以我的问题是：如何将变量从一级实例传递到三级实例？

如何重写wxPython实例以允许定义其他变量？

或者，是否可以创建自定义事件处理程序来传递必要的数据？

澄清。。。

我正在使用Python，我想我理解使用类和带有Tkinter和wxPython(在这个项目中使用)框架的GUI编程的基本原理。我已经编写了一个从用户那里获取一些数据的主类/实例，我希望能够传递self.main_instance_var中存储的信息，并将其传递给第二个类/实例(在本例中，是从第一个类调用的进度对话框窗口)。

当我试图在进度对话框中使用上述模型时，出现了一个非常不格式化的语法错误(“关键字arg之后是非关键字arg”)。阻止我进一步将变量从“进度”对话框窗口传递到工作线程。如果我得到一个异常，那将是一件事，但语法错误我不明白。下面是一个简短的例子：class ProgressDialog(wx.Dialog):

def __init__(self, parent, title, myVar): # Generates syntax error on this line
super(ProgressDialog, self).__init__(parent=parent,
title=title, size=(500, 110))
self.var = myVar
基本来源(按要求，很抱歉这么脏)：import time
import os, sys, wx
from ftplib import FTP_TLS
from threading import Thread
from wx.lib.pubsub import Publisher
########################################################################
class FtpValues(object):
""" Returns a property attribute - called by FtpFileTransfer
Used to set values/variables for Host, USERID, PASSWD, FILE """
#----------------------------------------------------------------------
def __init__(self):
self.varList = None
#----------------------------------------------------------------------
def GetValues(self):
return self.varList
#----------------------------------------------------------------------
def SetValues(self, HOST, USERID, PASSWD, FILE):
self.varList = [HOST, USERID, PASSWD, FILE]
#----------------------------------------------------------------------
def DelValues(self):
del self.valList
Values = property(GetValues, SetValues, DelValues, "Set/Get FtpValues")
# http://docs.python.org/library/functions.html#property
########################################################################
class FtpFileTransfer(Thread):
"""Test Worker Thread Class."""
#----------------------------------------------------------------------
def __init__(self):
"""Init Worker Thread Class."""
Thread.__init__(self)
self.StartTransfer() # start the thread
#----------------------------------------------------------------------
def StartTransfer(self): # was named run - started automatically
"""Run Worker Thread.""" # when called by the start method
# This is the code executing in the new thread.
HOST, USERID, PASSWD, FILE = FtpValues.Values
BLOCKSIZE = 57344
try:
ftp = FTP_TLS(HOST)
ftp.login(USERID, PASSWD)
ftp.prot_p()
ftp.voidcmd("TYPE I")
f = open(FILE, 'rb')
datasock, esize = ftp.ntransfercmd(
'STOR %s' % os.path.basename(FILE))
size = os.stat(FILE)[6]
bytes_so_far = 0
while 1:
buf = f.read(BLOCKSIZE)
if not buf:
break
datasock.sendall(buf)
bytes_so_far += len(buf)
msg = [bytes_so_far, size]
Publisher().sendMessage("update", msg)
except: raise
finally:
try:
datasock.close()
f.close()
ftp.voidresp()
ftp.quit()
print 'Complete...'
except: pass
wx.CallAfter(Publisher().sendMessage, "update", "Database Transfer Complete!")
########################################################################
class ProgressDialog(wx.Dialog):
def __init__(self, parent, title):
super(ProgressDialog, self).__init__(parent=parent,
title=title, size=(500, 110))
self.displayLbl = wx.StaticText(self, -1, 'Verifying Database Files... ', (20, 20)) #Preparing for Transfer...
self.gauge = wx.Gauge(self, -1, 100, (20, 45), (370, 24))
self.btn = btn = wx.Button(self, -1, 'Cancel', (400, 45), (-1, 25))
btn.Bind(wx.EVT_BUTTON, self.OnClose)
# listens for response from worker thread
Publisher().subscribe(self.updateDisplay, "update")
FtpFileTransfer()#.StartTransfer(HOST, USERID, PASSWD, FILE) #Start the FTP Worker Thread
#self.OnStart()
#----------------------------------------------------------------------
def run(self):
FtpFileTransfer(HOST, USERID, PASSWD, FILE)
#----------------------------------------------------------------------
def OnClose(self, event):
""" Place Holder """
if self.btn.GetLabel() == 'Finish':
# Do Something!
pass
return None
#----------------------------------------------------------------------
def updateDisplay(self, msg):
""" Receives data from thread and updates the display """
if isinstance(msg.data, list):
bytes_so_far, size = msg.data
k = 100 * bytes_so_far / size
self.displayLbl.SetLabel("Sent %d of %d bytes %.1f%%" % (bytes_so_far, size, 100 * bytes_so_far / size))
self.gauge.SetValue(k)
else:
self.displayLbl.SetLabel("%s" % msg.data)
#self.btn.Enable()
self.btn.SetLabel('Finish')
########################################################################
class MyForm(wx.Frame):
#----------------------------------------------------------------------
def __init__(self):
wx.Frame.__init__(self, None, wx.ID_ANY, "Tutorial")
# Add a panel so it looks the correct on all platforms
panel = wx.Panel(self, wx.ID_ANY)
self.displayLbl = wx.StaticText(panel, label="Amount of time since thread started goes here")
self.btn = btn = wx.Button(panel, label="Start Thread")
self.gauge = wx.Gauge(panel, -1, 100, size=(370, 24))
btn.Bind(wx.EVT_BUTTON, self.onButton)
sizer = wx.BoxSizer(wx.VERTICAL)
sizer.Add(self.displayLbl, 0, wx.ALL|wx.CENTER, 5)
sizer.Add(btn, 0, wx.ALL|wx.CENTER, 5)
sizer.Add(self.gauge, 0, wx.ALL|wx.CENTER, 5)
panel.SetSizer(sizer)
self.VarData()
# create a pubsub receiver
Publisher().subscribe(self.updateDisplay, "update")
#----------------------------------------------------------------------
def onButton(self, event):
"""
Runs the thread
"""
chgdep = ProgressDialog(None, title='File Transfer. . .')
chgdep.ShowModal()
#chgdep.Destroy()
#----------------------------------------------------------------------
def updateDisplay(self, msg):
"""
Receives data from thread and updates the display
"""
if isinstance(msg.data, list):
bytes_so_far, size = msg.data
k = 100 * bytes_so_far / size
self.displayLbl.SetLabel("Sent %d of %d bytes %.1f%%" % (bytes_so_far, size, 100 * bytes_so_far / size))
self.gauge.SetValue(k)
else:
self.displayLbl.SetLabel("%s" % msg.data)
self.btn.Enable()
#----------------------------------------------------------------------
def VarData(self):
HOST = '127.0.0.1'
USERID = 'test'
PASSWD = 'P@ssw0rd'
FILE = r'F:\Programming\temp\Test.zip'
varList = [HOST, USERID, PASSWD, FILE]
FtpValues.Values = HOST, USERID, PASSWD, FILE
#----------------------------------------------------------------------
# Run the program
if __name__ == "__main__":
app = wx.PySimpleApp()
frame = MyForm().Show()
app.MainLoop()

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