前几天，我估摸着做一个能生成qr code小程序，并能用wxpython在屏幕上显示出来。当然，我想用纯python实现，观望了一会后，我找到了三个候选：
github 上的 python-qrcode
sourceforge上的 pyqrcode
goolge code 上的 pyqrnative
我尝试了python-qrcode以及pyqrnative，因为它们能够运行在windows/mac/linux。也不需要依赖额外的其他库除了python图像库。pyqrcode项目需要其他一些先决条件，并且不能在windows上运行，所以我不想与之纠缠了。我最后使用了一些以前写过的一个photo viewer程序的代码，然后稍微地修改了一下，就成了qrcode的查看器了。
开始
正如我上面提到的，你只需要python图像库，gui部分我们将使用wxpython。python-qrcode相比pyqrnative生成图片更快，并包含了你见过的大多数qr码类型。
生成 qr codes
当你准备好所有需要的以后，你可以运行以下代码，看看python做了些啥：
import osimport wx try: import qrcodeexcept importerror: qrcode = none try: import pyqrnativeexcept importerror: pyqrnative = none ########################################################################class qrpanel(wx.panel): #---------------------------------------------------------------------- def __init__(self, parent): constructor wx.panel.__init__(self, parent=parent) self.photo_max_size = 240 sp = wx.standardpaths.get() self.defaultlocation = sp.getdocumentsdir() img = wx.emptyimage(240,240) self.imagectrl = wx.staticbitmap(self, wx.id_any, wx.bitmapfromimage(img)) qrdatalbl = wx.statictext(self, label=text to turn into qr code:) self.qrdatatxt = wx.textctrl(self, value=http://www.mousevspython.com, size=(200,-1)) instructions = name qr image file instructlbl = wx.statictext(self, label=instructions) self.qrphototxt = wx.textctrl(self, size=(200,-1)) browsebtn = wx.button(self, label='change save location') browsebtn.bind(wx.evt_button, self.onbrowse) deflbl = default save location: + self.defaultlocation self.defaultlocationlbl = wx.statictext(self, label=deflbl) qrcodebtn = wx.button(self, label=create qr with qrcode) qrcodebtn.bind(wx.evt_button, self.onuseqrcode) pyqrnativebtn = wx.button(self, label=create qr with pyqrnative) pyqrnativebtn.bind(wx.evt_button, self.onusepyqr) # create sizer self.mainsizer = wx.boxsizer(wx.vertical) qrdatasizer = wx.boxsizer(wx.horizontal) locationsizer = wx.boxsizer(wx.horizontal) qrbtnsizer = wx.boxsizer(wx.vertical) qrdatasizer.add(qrdatalbl, 0, wx.all, 5) qrdatasizer.add(self.qrdatatxt, 1, wx.all|wx.expand, 5) self.mainsizer.add(wx.staticline(self, wx.id_any), 0, wx.all|wx.expand, 5) self.mainsizer.add(qrdatasizer, 0, wx.expand) self.mainsizer.add(self.imagectrl, 0, wx.all, 5) locationsizer.add(instructlbl, 0, wx.all, 5) locationsizer.add(self.qrphototxt, 0, wx.all, 5) locationsizer.add(browsebtn, 0, wx.all, 5) self.mainsizer.add(locationsizer, 0, wx.all, 5) self.mainsizer.add(self.defaultlocationlbl, 0, wx.all, 5) qrbtnsizer.add(qrcodebtn, 0, wx.all, 5) qrbtnsizer.add(pyqrnativebtn, 0, wx.all, 5) self.mainsizer.add(qrbtnsizer, 0, wx.all|wx.center, 10) self.setsizer(self.mainsizer) self.layout() #---------------------------------------------------------------------- def onbrowse(self, event): dlg = wx.dirdialog(self, choose a directory:, style=wx.dd_default_style) if dlg.showmodal() == wx.id_ok: path = dlg.getpath() self.defaultlocation = path self.defaultlocationlbl.setlabel(save location: %s % path) dlg.destroy() #---------------------------------------------------------------------- def onuseqrcode(self, event): https://github.com/lincolnloop/python-qrcode qr = qrcode.qrcode(version=1, box_size=10, border=4) qr.add_data(self.qrdatatxt.getvalue()) qr.make(fit=true) x = qr.make_image() qr_file = os.path.join(self.defaultlocation, self.qrphototxt.getvalue() + .jpg) img_file = open(qr_file, 'wb') x.save(img_file, 'jpeg') img_file.close() self.showqrcode(qr_file) #---------------------------------------------------------------------- def onusepyqr(self, event): http://code.google.com/p/pyqrnative/ qr = pyqrnative.qrcode(20, pyqrnative.qrerrorcorrectlevel.l) qr.adddata(self.qrdatatxt.getvalue()) qr.make() im = qr.makeimage() qr_file = os.path.join(self.defaultlocation, self.qrphototxt.getvalue() + .jpg) img_file = open(qr_file, 'wb') im.save(img_file, 'jpeg') img_file.close() self.showqrcode(qr_file) #---------------------------------------------------------------------- def showqrcode(self, filepath): img = wx.image(filepath, wx.bitmap_type_any) # scale the image, preserving the aspect ratio w = img.getwidth() h = img.getheight() if w > h: neww = self.photo_max_size newh = self.photo_max_size * h / w else: newh = self.photo_max_size neww = self.photo_max_size * w / h img = img.scale(neww,newh) self.imagectrl.setbitmap(wx.bitmapfromimage(img)) self.refresh() ########################################################################class qrframe(wx.frame): #---------------------------------------------------------------------- def __init__(self): constructor wx.frame.__init__(self, none, title=qr code viewer, size=(550,500)) panel = qrpanel(self) if __name__ == __main__: app = wx.app(false) frame = qrframe() frame.show() app.mainloop()
python-qrcode生成效果图：
pyqrnative生成效果图：