self.sums = []
for i in range(numcol):
lab = Label(self, text='?', relief=SUNKEN)
lab.grid(row=numrow+1, column=i, sticky=NSEW)
self.sums.append(lab)
Button(self, text='Sum', command=self.onSum).grid(row=0, column=0)
Button(self, text='Print', command=self.onPrint).grid(row=0, column=1)
Button(self, text='Clear', command=self.onClear).grid(row=0, column=2)
Button(self, text='Load', command=self.onLoad).grid(row=0, column=3)
Quitter(self).grid(row=0, column=4) # fails: Quitter(self).pack()
def onPrint(self):
for row in self.rows:
for col in row:
print(col.get(), end=' ')
print()
print()
def onSum(self):
tots = [0] * self.numcol
for i in range(self.numcol):
for j in range(self.numrow):
tots[i] += eval(self.rows[j][i].get()) # sum current data
for i in range(self.numcol):
self.sums[i].config(text=str(tots[i]))
def onClear(self):
for row in self.rows:
for col in row:
col.delete('0', END) # delete content
col.insert(END, '0.0') # preserve display
for sum in self.sums:
sum.config(text='?')
def onLoad(self):
file = askopenfilename()
if file:
for row in self.rows:
for col in row: col.grid_forget() # erase current gui
for sum in self.sums:
sum.grid_forget()
filelines = open(file, 'r').readlines() # load file data
self.numrow = len(filelines) # resize to data
self.numcol = len(filelines[0].split())
self.makeWidgets(self.numrow, self.numcol)
for (row, line) in enumerate(filelines): # load into gui
fields = line.split()
for col in range(self.numcol):
self.rows[row][col].delete('0', END)
self.rows[row][col].insert(END, fields[col])
578 | Chapter 9: A tkinter Tour, Part 2