473,326 Members | 2,134 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,326 software developers and data experts.

how to use property

My question is how should I use "property" which wraps up
__get_channel() and __set_channel()in the following program.
I tried the program that written below, and it worked. Then I tried:
channel = property(__get_channel,__set_channel) as in comment 1, 2,
and 3,

but it generates the error:
Traceback (most recent call last):
File "C:/WINDOWS/desktop/test.py", line 41, in -toplevel-
main()
File "C:/WINDOWS/desktpo/test.py", line 37, in main
tv.change_channel(choice)
File "C:/WINDOWS/desktop/test.py", line 27, in change_channel
self.channel(choice)
TypeError: 'int' object is not callable

I am now studying class, so want to use property.
This program simulates changing channel number 1 through 10 on TV.
How should I use property here?

---------------------------------------
##simulating a TV

##defining class
class TV(object):
def __init__(self, channel = 1):
self.__channel = channel
self.__volume = volume
print "the default channel is", self.__channel

def __get_channel(self):
return self.__channel

def __set_channel(self, choice):
if choice == "+":
self.__channel += 1
elif choice == "-":
self.__channel -= 1
if self.__channel == 0:
self.__channel = 10
elif self.__channel == 11:
self.__channel = 1

#comment1: channel = property(__get_channel, __set_channel)

def change_channel(self, choice):
self.__set_channel(choice)
print self.__get_channel()

#comment2: self.channel(choice)
#comment3: print "channel: ", self.channel
##main part
def main():
tv = TV()
choice = " "
while choice:
choice = raw_input("choice (+ / -): ")
tv.change_channel(choice)
##starting program
main()

Jul 18 '05 #1
2 1693
try this: self.channel = choice

Jul 18 '05 #2
ne********@myrealbox.com said the following on 2/25/2005 5:25 AM:
My question is how should I use "property" which wraps up
__get_channel() and __set_channel()in the following program.
I tried the program that written below, and it worked. Then I tried:
channel = property(__get_channel,__set_channel) as in comment 1, 2,
and 3,

but it generates the error:
Traceback (most recent call last):
File "C:/WINDOWS/desktop/test.py", line 41, in -toplevel-
main()
File "C:/WINDOWS/desktpo/test.py", line 37, in main
tv.change_channel(choice)
File "C:/WINDOWS/desktop/test.py", line 27, in change_channel
self.channel(choice)
TypeError: 'int' object is not callable

I am now studying class, so want to use property.
This program simulates changing channel number 1 through 10 on TV.
How should I use property here?

def change_channel(self, choice):
self.__set_channel(choice)
print self.__get_channel()

#comment2: self.channel(choice)

You see comment#2... You say self.channel(choice). self.channel is an
int object that you are trying to call - channel(choice) - and that is
what your exception states when it says 'int object is not callable'.

You probably meant self.channel = choice

Also, there is a problem in your posted version. You have not defined
volume before usage. So I added it to __init__(..,.., volume=120) to
make it work.

Cheers,
-Kartic
Jul 18 '05 #3

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

3
by: Johnny M | last post by:
using Access 2003 Pardon the subject line, but I don't have a better word for this strange behavior (or behavior I don't understand!!!) I have a class module named DepreciationFactor. One of...
2
by: Edward Diener | last post by:
How does one specify in a component that a property is a pointer to another component ? How is this different from a property that is actually an embedded component ? Finally how is one notified in...
0
by: Brian Young | last post by:
Hi all. I'm using the Property Grid control in a control to manage a windows service we have developed here. The windows service runs a set of other jobs that need to be managed. The control...
3
by: Marty McFly | last post by:
Hello, I have a control class that inherits from System.Web.UI.WebControls.Button. When I drag this control from the "My User Controls" tab in the toolbox onto the form, I want it to reflect the...
15
by: Sam Kong | last post by:
Hello! I got recently intrigued with JavaScript's prototype-based object-orientation. However, I still don't understand the mechanism clearly. What's the difference between the following...
15
by: Lauren Wilson | last post by:
Owning your ideas: An essential tool for freedom By Daniel Son Thinking about going into business? Have an idea that you think will change the world? What if you were told that there was no way...
0
by: Memfis | last post by:
While I was looking through the group's archives I came across a discussion on doing properties (as known from Delphi/C#/etc) in C++. It inspired me to do some experimenting. Here's what I came up...
0
ADezii
by: ADezii | last post by:
The motivation for this Tip was a question asked by one of our Resident Experts, FishVal. The question was: How to Declare Default Method/Property in a Class Module? My response to the question was...
1
by: cday119 | last post by:
I have a Class with about 10 properties. All properties return right except for one. It is real annoying and I can't see why its not working. Maybe someone else can see something. It is the...
10
by: Derek Hart | last post by:
I can set focus to my property grid by using propgrid.Focus - but how can I set the default property that is always first? Or just set focus to the default property? Can this be done?
0
by: ryjfgjl | last post by:
ExcelToDatabase: batch import excel into database automatically...
0
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
0
by: Vimpel783 | last post by:
Hello! Guys, I found this code on the Internet, but I need to modify it a little. It works well, the problem is this: Data is sent from only one cell, in this case B5, but it is necessary that data...
0
by: jfyes | last post by:
As a hardware engineer, after seeing that CEIWEI recently released a new tool for Modbus RTU Over TCP/UDP filtering and monitoring, I actively went to its official website to take a look. It turned...
0
by: ArrayDB | last post by:
The error message I've encountered is; ERROR:root:Error generating model response: exception: access violation writing 0x0000000000005140, which seems to be indicative of an access violation...
1
by: PapaRatzi | last post by:
Hello, I am teaching myself MS Access forms design and Visual Basic. I've created a table to capture a list of Top 30 singles and forms to capture new entries. The final step is a form (unbound)...
1
by: CloudSolutions | last post by:
Introduction: For many beginners and individual users, requiring a credit card and email registration may pose a barrier when starting to use cloud servers. However, some cloud server providers now...
1
by: Shællîpôpï 09 | last post by:
If u are using a keypad phone, how do u turn on JavaScript, to access features like WhatsApp, Facebook, Instagram....
0
by: Faith0G | last post by:
I am starting a new it consulting business and it's been a while since I setup a new website. Is wordpress still the best web based software for hosting a 5 page website? The webpages will be...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.