Question

Allright, I’m completely new to programming but I feel I am picking it up quite quickly, I’ve gone straight into Objective-C and I know some would say that wasn’t wise but anyway.

Heres the sitch, In my ViewController.m I have:

@implementation ViewController

CGPoint Destination;  --->irrelevant for this question just giving a layout
CGFloat xamt, yamt;  ---> irrelevant for this question just giving a layout
CGFloat speed = 30;

so my question is, How/where would I put code to get a UISlider to change the speed value?

Answer 1

Instantiate an UISlider and add it to one of the views that are currently displayed (I’ll assume you use a view controller, and it is self):

UISlider *s = [[UISlider alloc] initWithFrame:CGRectMake(20, 10, 280, 44)];
[s addTarget:self action:@selector(sliderValueChanged:) forControlEvents:UIControlEventValueChanged];
[self.view addSubview:s];
[s release];

Then implement the slider’s action method (still in your view controller’s class):

- (void)sliderValueChanged:(UISlider *)s
{
    speed = 30 * s.value;
}

Hope this helps.

P.s. : good advice: seriously, learn C first and master it before doing serious Objective-C or you’ll get confused later or sooner, and wasting your users’ RAM is not fun 🙂