A simple clock

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

deepstar@gmail.com - 31 Oct 2005 17:42 GMT

I'm trying to create a simple clock and have this code so far:

- (void)awakeFromNib {
scheduler = [NSTimer scheduledTimreWithInterval:1.0
target:self
selector:@selector(timeCheck:)
userInfo:nil
repeats:YES];
[scheduler retain];
{

- (void) timeCheck :(NSTimer *)aTimerl
{
[scheduler invalidate];
[scheduelr release];
scheduler = nil;
[showTime setStringValue:scheduler];
}

But I get this error message "NSTimer discarding exception 'Invalid
parameter not satisfying: aString !=nil". Am I far off target or have I
just gotten the timeCheck function wrong? (I suspect that that's the
culprit). I have tried reading through the Apple documentation for both
NSTimer and NSCalendarDate but they are hard to grasp since they use
too general concepts.

Reply to this Message

deepstar@gmail.com - 31 Oct 2005 17:51 GMT

I just realised that I had a mistake in the timeCheck function, the
revised version now looks like

- (void) timeCheck :(NSTimer *)aTimerl
{
NSCalendarDate *myTime = [NSCalendarDate now];
[scheduler invalidate];
[scheduelr release];
scheduler = nil;
[showTime setStringValue:myTime];
}

The error message I get now is: NSTimer discarding exception '***
+[NSCalendarDate now]: selector not recognized' that raised during
firing of timer with target 3486a0 and selector 'timecheck:'. This
error is displayed once every second so I guess the that at least
NSTimer method is working properly.

Reply to this Message

Tom Harrington - 31 Oct 2005 18:51 GMT

> I just realised that I had a mistake in the timeCheck function, the
> revised version now looks like
[quoted text clipped - 13 lines]
> error is displayed once every second so I guess the that at least
> NSTimer method is working properly.

The error message is pretty clear. NSCalendarDate does not have a
method called +now, so you're getting an exception when you try to call
it.

Signature

Tom "Tom" Harrington
Macaroni, Automated System Maintenance for Mac OS X.
Version 2.0: Delocalize, Repair Permissions, lots more.
See http://www.atomicbird.com/

Reply to this Message

deepstar@gmail.com - 31 Oct 2005 19:07 GMT

Well your comment made me take another look at the code and I instantly
saw that NSCalendarDate *myTime = [NSCalendarDate now]; should be

NSCalendarDate *myTime = [NSCalendarDate date];

Now that that's fixed I don't receive any more error messages but the
textfield won't update! I really hate to bug you guys about small
problems like this one but it has been boggling me for over three days
now.

Reply to this Message

Tom Harrington - 31 Oct 2005 19:52 GMT

> Well your comment made me take another look at the code and I instantly
> saw that NSCalendarDate *myTime = [NSCalendarDate now]; should be
[quoted text clipped - 5 lines]
> problems like this one but it has been boggling me for over three days
> now.

Maybe it's because you invalidate your timer after the first time it
fires? You tell it to repeat when you create it, but then you prevent
it from actually doing so.

Signature

Tom "Tom" Harrington
Macaroni, Automated System Maintenance for Mac OS X.
Version 2.0: Delocalize, Repair Permissions, lots more.
See http://www.atomicbird.com/

Reply to this Message

deepstar@gmail.com - 31 Oct 2005 20:02 GMT

Tom Harrington skrev:

> > Well your comment made me take another look at the code and I instantly
> > saw that NSCalendarDate *myTime = [NSCalendarDate now]; should be
[quoted text clipped - 15 lines]
> Version 2.0: Delocalize, Repair Permissions, lots more.
> See http://www.atomicbird.com/

That seems to have solved the problem Tom, thanks for walking me
through it. I plan to put all of my current and future projects on a
Cocoa site for newbies so you've probably helped more people than you
think!

Reply to this Message

Mac Forum / Programming / Mac Programming / October 2005

A simple clock