如何运行 nfcpy card reader system on wxPython GUI application

Question

我是 wxPython GUI 应用程序的新手

我想创建我的 python 脚本作为 GUI 应用程序

This is my sample script

import binascii
import nfc

class MyCardReader(object):

   def on_connect(self, tag):
      print "touched"
      self.idm = binascii.hexlify(tag.idm)
      return True

   def read_id(self):
      clf = nfc.ContactlessFrontend('usb')
      try:
         clf.connect(rdwr={'on-connect': self.on_connect})
      finally:
         clf.close()

if __name__ == '__main__':
  cr = MyCardReader()
  while True:
    print "touch card:"
    cr.read_id()
    print "released"
    print cr.idm

how to run the above script as GUI app using wxPython, i was already try but it doesnt work, what is wrong in my code.

#-*- encoding: utf-8 -*-
import wx
import nfc
import binascii
class MyFrame(wx.Frame):

   def __init__(self, parent, title):
      wx.Frame.__init__(self, parent, title=title, size=(400, 500))
      panel = wx.Panel(self)
      self.Show(True)
      while True:
        clf = nfc.ContactlessFrontend('usb')
        clf.connect(rdwr={'on-connect': self.on_connect})
        self.text = wx.StaticText(panel, label='i want to print the return value here', pos=(100, 100))

  def on_connect(self, tag):
      self.idm = binascii.hexlify(tag.idm)
      return self.idm

app = wx.App(False)
frame = MyFrame(None, 'card reader app')
app.MainLoop()

Answer 1

您已将您的代码投入无限的 While True 循环，这意味着 Gui 主循环永远不会到达运行。
您应该根据来自卡片 reader 的输入添加一个 event，或者为了让您开始，只需添加一个按钮并在按下按钮时访问 reader。这会让您快速起床运行。
这是您的代码，经过调整后可以在我的电脑上运行，只是为了证明它可以正常工作。
注意 self.text.SetLabel()

的使用

import wx
#import nfc
import binascii
class MyFrame(wx.Frame):

    def __init__(self, parent, title):
        wx.Frame.__init__(self, parent, title=title, size=(400, 500))
        panel = wx.Panel(self)
        self.text = wx.StaticText(panel, label='i want to print the return value here', pos=(100, 100))
        self.read = wx.Button(panel, -1, label="Read Card", pos=(100, 200))
        self.read.Bind(wx.EVT_BUTTON, self.on_button)
        self.Show()
        self.n = 0

    def on_button(self,event):
#        clf = nfc.ContactlessFrontend('usb')
#        clf.connect(rdwr={'on-connect': self.on_connect})
        self.n+=1
        self.on_connect("abc")
        self.text.SetLabel("Card Value "+self.idm+" "+str(self.n))

    def on_connect(self, tag):
        self.idm = binascii.hexlify(tag)#.idm)
        return self.idm

app = wx.App()
frame = MyFrame(None, 'card reader app')
app.MainLoop()

Answer 2

nfc.ContactlessFrontend.connect() 方法在调用者线程上下文中运行，因此在至少连接一个标签之前不会返回（如果 'on-connect' 回调 returns True 它将进一步等待直到标签消失）。 wx.App.mainLoop() 也在调用者线程上下文中运行分派 window 事件。因此，正确的方法是运行在单独的线程中发现标签并将事件发送到渲染帧。下面是一个示例，当标签靠近 reader.

时显示标签标识符

#!/usr/bin/env python
import wx
import wx.lib.newevent
import nfc
import threading
from binascii import hexlify

ShowCardEvent, SHOW_CARD_EVENT = wx.lib.newevent.NewEvent()
GoneCardEvent, GONE_CARD_EVENT = wx.lib.newevent.NewEvent()


class TagReader(threading.Thread):
    def __init__(self, wx_frame):
        super(TagReader, self).__init__(name="TagReader")
        self.terminate = False
        self.wx_frame = wx_frame

    def run(self):
        clf = nfc.ContactlessFrontend('usb')
        rdwr_options = {
            'on-connect': self.on_tag_connect,
            'on-release': self.on_tag_release
        }
        while not self.terminate:
            clf.connect(rdwr=rdwr_options, terminate=lambda: self.terminate)

    def on_tag_connect(self, tag):
        wx.PostEvent(self.wx_frame, ShowCardEvent(tag=tag))
        return True

    def on_tag_release(self, tag):
        wx.PostEvent(self.wx_frame, GoneCardEvent())


class Frame(wx.Frame):
    def __init__(self, title):
        super(Frame, self).__init__(None, title=title, size=(500, 200))
        self.text = wx.StaticText(wx.Panel(self), pos=(100, 100))
        self.Bind(SHOW_CARD_EVENT, self.show_card_event)
        self.Bind(GONE_CARD_EVENT, self.gone_card_event)
        self.Bind(wx.EVT_CLOSE, self.close_window_event)
        wx.PostEvent(self, GoneCardEvent())
        self.Show()

    def close_window_event(self, event):
        self.Destroy()

    def show_card_event(self, event):
        self.text.SetLabel("Card ID {}".format(hexlify(event.tag.identifier)))

    def gone_card_event(self, event):
        self.text.SetLabel("no card")


app = wx.App()
reader = TagReader(Frame('card reader app'))
reader.start()
app.MainLoop()
reader.terminate = True  # tell the reader to terminate
reader.join()  # and wait for the reader thread to finish

如何运行 nfcpy card reader system on wxPython GUI application

how to run nfcpy card reader system on wxPython GUI application

python

user-interface

wxpython

nfc-p2p