Trouble with NSTimer

Question

I am having so much trouble with NSTimers. I have used them before, but this timer just does not want to fire.

-(void) enqueueRecordingProcess
{
    NSLog(@"made it!");
    NSTimer *time2 = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(warnForRecording) userInfo:nil repeats:YES];

}

-(void) warnForRecording
{
    NSLog(@"timer ticked!");
    if (trv > 0) {
        NSLog(@"Starting Recording in %i seconds.", trv);
    }
}

I don't see why this won't run. I even tried this:

- (void)enqueueRecordingProcess
{
    NSLog(@"made it!");
    [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(warnForRecording) userInfo:nil repeats:YES];
}

 - (void)warnForRecording
{
    NSLog(@"timer ticked!");
}

What is wrong?

score 2 · Accepted Answer · answered Jun 03 '12 at 23:38

2

Not sure if this fixes it but from the docs:

The message to send to target when the timer fires. The selector must have the following signature:
- (void)timerFireMethod:(NSTimer*)theTimer
The timer passes itself as the argument to this method.

answered Jun 03 '12 at 23:38

kevboh

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I tried this as well. It still is not running. The only way I can make it run is using [timer fire], but that only makes it run once. – Ben Reed Jun 03 '12 at 23:45
4

@rbvcode are you running this via a command line app or through a Cocoa app? NSTimer won't work in a Command line app because there is no runloop. – Richard J. Ross III Jun 03 '12 at 23:46
@RichardJ.RossIII ok... that explains it. Thank you so much. Nobody explained to me that their is no run loop in a Command line app. I will need to process my app in a completely different way. Sorry for not knowing this. This is the first time that I have ever developed a command line app that needed a timer. Once again, Thanks for your assistance. – Ben Reed Jun 03 '12 at 23:56
1

To run the run loop, you can just call [[NSRunLoop runloop] run] or something like that at the end of main. – Ken Aspeslagh Jun 04 '12 at 02:24
Re: using the run loop in a command line program: see http://stackoverflow.com/questions/2154600/command-line-cocoa-app-no-gui – Jon Gauthier May 22 '13 at 04:37

score 0 · Answer 2 · answered Jun 04 '12 at 04:12

0

I am not sure about you specifics, but you need to service the runloop in order to get events, including timers.

answered Jun 04 '12 at 04:12

Grady Player

14,399
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score 0 · Answer 3 · answered Jun 13 '13 at 04:00

// Yes.  Here is sample code (tested on OS X 10.8.4, command-line).
// Using ARC:
// $ cc -o timer timer.m -fobjc-arc -framework Foundation
// $ ./timer
//

#include <Foundation/Foundation.h>

@interface MyClass : NSObject
@property NSTimer *timer;
-(id)init;
-(void)onTick:(NSTimer *)aTimer;
@end

@implementation MyClass
-(id)init {
    id newInstance = [super init];
    if (newInstance) {
        NSLog(@"Creating timer...");
        _timer = [NSTimer scheduledTimerWithTimeInterval:1.0
            target:self
            selector:@selector(onTick:)
            userInfo:nil
            repeats:YES];
    }
    return newInstance;
}

-(void)onTick:(NSTimer *)aTimer {
    NSLog(@"Tick");
}
@end

int main() {
    @autoreleasepool {
        MyClass *obj = [[MyClass alloc] init];
        [[NSRunLoop currentRunLoop] run];
    }
    return 0;
}

Trouble with NSTimer

3 Answers3