gui/qt/qrcodewidget.py

   1 from PyQt4.QtGui import *
   2 from PyQt4.QtCore import *
   3 import PyQt4.QtCore as QtCore
   4 import PyQt4.QtGui as QtGui
   5
   6 from electrum import bmp, pyqrnative
   7
   8
   9 class QRCodeWidget(QWidget):
  10
  11     def __init__(self, data = None):
  12         QWidget.__init__(self)
  13         self.addr = None
  14         self.qr = None
  15         if data:
  16             self.set_addr(data)
  17             self.update_qr()
  18
  19     def set_addr(self, addr):
  20         if self.addr != addr:
  21             if len(addr) < 128:
  22                 MinSize = 210
  23             else:
  24                 MinSize = 500
  25             self.setMinimumSize(MinSize, MinSize)
  26             self.addr = addr
  27             self.qr = None
  28             self.update()
  29
  30     def update_qr(self):
  31         if self.addr and not self.qr:
  32             for size in range(len(pyqrnative.QRUtil.PATTERN_POSITION_TABLE)): # [4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32]:
  33                 try:
  34                     self.qr = pyqrnative.QRCode(size, pyqrnative.QRErrorCorrectLevel.L)
  35                     self.qr.addData(self.addr)
  36                     self.qr.make()
  37                     break
  38                 except:
  39                     self.qr=None
  40                     continue
  41             self.update()
  42
  43     def paintEvent(self, e):
  44
  45         if not self.addr:
  46             return
  47
  48         black = QColor(0, 0, 0, 255)
  49         white = QColor(255, 255, 255, 255)
  50
  51         if not self.qr:
  52             qp = QtGui.QPainter()
  53             qp.begin(self)
  54             qp.setBrush(white)
  55             qp.setPen(white)
  56             qp.drawRect(0, 0, 198, 198)
  57             qp.end()
  58             return
  59
  60         k = self.qr.getModuleCount()
  61         qp = QtGui.QPainter()
  62         qp.begin(self)
  63         r = qp.viewport()
  64         boxsize = min(r.width(), r.height())*0.8/k
  65         size = k*boxsize
  66         left = (r.width() - size)/2
  67         top = (r.height() - size)/2
  68
  69         # Make a white margin around the QR in case of dark theme use:
  70         margin = 10
  71         qp.setBrush(white)
  72         qp.drawRect(left-margin, top-margin, size+(margin*2), size+(margin*2))
  73
  74         for r in range(k):
  75             for c in range(k):
  76                 if self.qr.isDark(r, c):
  77                     qp.setBrush(black)
  78                     qp.setPen(black)
  79                 else:
  80                     qp.setBrush(white)
  81                     qp.setPen(white)
  82                 qp.drawRect(left+c*boxsize, top+r*boxsize, boxsize, boxsize)
  83         qp.end()
  84