import sys

from PySide.QtCore import *

from PySide.QtGui import *

import urllib2

class Form(QDialog):

def __init__(self, parent=None):

super(Form, self).__init__(parent)

date = self.getdata()

rates = sorted(self.rates.keys())

dateLabel = QLabel(date)

self.fromComboBox = QComboBox()

self.fromComboBox.addItems(rates)

self.fromSpinBox = QDoubleSpinBox()

self.fromSpinBox.setRange(0.01, 10000000.00)

self.fromSpinBox.setValue(1.00)

self.toComboBox = QComboBox()

self.toComboBox.addItems(rates)

self.toLabel = QLabel("1.00")

grid = QGridLayout()

grid.addWidget(dateLabel, 0, 0)

grid.addWidget(self.fromComboBox, 1, 0)

grid.addWidget(self.fromSpinBox, 1, 1)

grid.addWidget(self.toComboBox, 2, 0)

grid.addWidget(self.toLabel, 2, 1)

self.setLayout(grid)

self.connect(self.fromComboBox, SIGNAL("currentIndexChanged(int)"), self.updateUi)

self.connect(self.toComboBox, SIGNAL("currentIndexChanged(int)"), self.updateUi)

self.connect(self.fromSpinBox, SIGNAL("valueChanged(double)"), self.updateUi)

def updateUi(self):

to = self.toComboBox.currentText()

from_ = self.fromComboBox.currentText()

amount = (self.rates[from_] / self.rates[to]) * self.fromSpinBox.value()

self.toLabel.setText("%0.2f" % amount)

def getdata(self):

self.rates = {}

try:

date = "Unknown"

fh = urllib2.urlopen("http://www.bankofcanada.ca/en/markets/csv/exchange_eng.csv")

for line in fh:

line = line.rstrip()

if not line or line.startswith(("#", "Closing")):

continue

fields = line.split(",")

if line.startswith("Date "):

date = fields[-1]

else:

try:

value = float(fields[-1])

self.rates[fields[0]] = value

except ValueError:

pass

return "Exchange rates date: " + date

except Exception, e:

return "Failued to download:\n%s" % e

app = QApplication(sys.argv)

form = Form()

form.show()

app.exec_()