Xcode 5.1-按钮禁用/启用不起作用？

Question

App with 4 buttons - just want to control their behavior - ie push a button and it is disabled while others are enabled.

From other questions/answers here, I've created the following .h entries:

@interface TestButtonsViewController : UIViewController
- (IBAction)b1:(id)sender;
- (IBAction)b2:(id)sender;
- (IBAction)b3:(id)sender;
- (IBAction)b4:(id)sender;

@property (retain, nonatomic) IBOutlet UIButton *b1;
@property (retain, nonatomic) IBOutlet UIButton *b2;
@property (retain, nonatomic) IBOutlet UIButton *b3;
@property (retain, nonatomic) IBOutlet UIButton *b4;

and the .m

- (IBAction)b1:(id)sender {

UIButton *b1 = (UIButton *) sender;
b1.enabled = NO;
UIButton *b2 = (UIButton *) sender;
b2.enabled = YES;
UIButton *b3 = (UIButton *) sender;
b3.enabled = NO;
UIButton *b4 = (UIButton *) sender;
b4.enabled = NO;
}

- (IBAction)b2:(id)sender {

UIButton *b1 = (UIButton *) sender;
b1.enabled = NO;
UIButton *b2 = (UIButton *) sender;
b2.enabled = NO;
UIButton *b3 = (UIButton *) sender;
b3.enabled = YES;
UIButton *b4 = (UIButton *) sender;
b4.enabled = NO;
}

- (IBAction)b3:(id)sender {

UIButton *b1 = (UIButton *) sender;
b1.enabled = NO;
UIButton *b2 = (UIButton *) sender;
b2.enabled = NO;
UIButton *b3 = (UIButton *) sender;
b3.enabled = NO;
UIButton *b4 = (UIButton *) sender;
b4.enabled = YES;
}

- (IBAction)b4:(id)sender {

UIButton *b1 = (UIButton *) sender;
b1.enabled = YES;
UIButton *b2 = (UIButton *) sender;
b2.enabled = YES;
UIButton *b3 = (UIButton *) sender;
b3.enabled = YES;
UIButton *b4 = (UIButton *) sender;
b4.enabled = NO;
}

When I save, build, run and push the buttons starting at 1 and going down the buttons 1 and 2 do disable after I push them; but when I press 3 it doesn't; furthermore when I press 4 it doesn't enable 1 and 2.

Answer 1

Your logic is incorrect behavior for what you want to do, you can't cast multiple buttons from the same sender and expect them to behave properly. Use your properties you already have instead and try this:

- (IBAction)b1:(id)sender 
{
    self.b1.enabled = NO;
    self.b2.enabled = YES;
    self.b3.enabled = NO;
    self.b4.enabled = NO;
}

- (IBAction)b2:(id)sender 
{
    self.b1.enabled = NO;
    self.b2.enabled = NO;
    self.b3.enabled = YES;
    self.b4.enabled = NO;
}

- (IBAction)b3:(id)sender 
{
    self.b1.enabled = NO;
    self.b2.enabled = NO;
    self.b3.enabled = NO;
    self.b4.enabled = YES;
}

- (IBAction)b4:(id)sender 
{
    self.b1.enabled = YES;
    self.b2.enabled = YES;
    self.b3.enabled = YES;
    self.b4.enabled = NO;
}

Answer 2

What you are looking for is Button. userInteractionEnabled = NO