Question

I Have a textfield and I need the user to put a number in there, this number I need to transform into a float value and take it to another view. I can’t find my error… Xcode says it is on the “float valor = [[_inserir.text ] floatvalue];“line. If somebody could find where is my error, thanks.

first view .h:

#import <UIKit/UIKit.h>

@interface CedulasFirstViewController : UIViewController
@property (strong, nonatomic) IBOutlet UITextField *inserir;
- (IBAction)calc:(id)sender;

@end

first view .m: (the underline before my variable name, xcode put it by itself, taking it out doesn’t change anything)

#import "CedulasFirstViewController.h"
#import "CedulasSecondViewController.h"

@interface CedulasFirstViewController ()

@end

@implementation CedulasFirstViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (IBAction)calc:(id)sender {

    float valor = [[_inserir.text ] floatvalue];

    CedulasSecondViewController *second [[[CedulasSecondViewController alloc] init]];

    second.valor = self.valor;

}
@end

second view .h:

#import <UIKit/UIKit.h>

@interface CedulasSecondViewController : UIViewController{


}

@end

second view .m:

#import "CedulasSecondViewController.h"

@interface CedulasSecondViewController ()

@end

@implementation CedulasSecondViewController

- (void)viewDidLoad
{

    NSString *numberFromTF [[NSString alloc] initWithFormat:@"%.2f", valor];

    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

Thanks

EDIT:

if someone could explain me why xcode says to put this underline before the variable

Answer 1

There are a few things you need to do here.

First, you’ve created a property in CedulasFirstViewController.h, so you need to synthesize it in CedulasFirstViewController.m. In CedulasFirstViewController.m, beneath the line @implementation CedulasFirstViewController, type

@synthesize inserir;

Then, in the line float valor = [[_inserir.text ] floatvalue];, there are a couple errors. You’re treating your property like an instance variable, so instead of _inserir.text you should use self.inserir.text. Also, you should remove the inner pair of brackets, because brackets are used for when functions are being performed, and there’s no function being performed in self.inserir.text. self.inserir.text (or _inserir.text, for that matter) is simply an object.

All this means that the line producing the error should look like this:

float valor = [self.inserir.text floatvalue];

There seem to be some other problems with this code, but if you ask about them those should be a separate question.