Question

I am creating a calculator view that uses sliders to set textbox values. Each textbox has a slider that corresponds to it. The code for updating textbox values is as follows:

- (void) updateAlphaTextField:(id)sender 
{
    int value = [alphaSlider value];

    NSString *stringValue = [NSString stringWithFormat:@"%d",value];

    [alphaTextField setText:stringValue];    
}

However I have about 20 textboxes (and 20 corresponding sliders) that I would like to demonstrate this behavior and I don’t want to write 20 of these update functions.

Is there a function that I can write that could watch all the sliders and update a corresponding textbox with the right value? If so, how do I make my IB connections to get it to work? (The above function required 1 IB connection to be made)

Or even better is there a Cocoa Touch function that would allow me to do this easily?

Answer 1

Put tags in your UITextFields and UISliders. For instance: UITextField 1, would have tag 1 and the UISlider 1, would also have tag 1. Then, create an IBOutlet collection with all your UITextFields. You can use this to help you out:

http://www.bobmccune.com/2011/01/31/using-ios-4s-iboutletcollection/

In your function do this:

- (void) updateAlphaTextField:(id)sender 
{
    int value = [alphaSlider value];

    NSString *stringValue = [NSString stringWithFormat:@"%d",value];

    UISlider *senderSlider = (UISlider*)sender;

    for(UITextField *textField in textFieldCollection){
       if(textField.tag==senderSlider.tag){
           [textField setText:stringValue];   
       }
    }

}