An iPhone (Cocoa) segment control that acts like a single toggle button.

AKSingleSegmentedControl.h

// AKSingleSegmentedControl.h
// By Henrik Nyh <http://henrik.nyh.se> 2010-05-14 under the MIT license.
// http://gist.github.com/401670
//
// A segment control that acts like a single toggle button.

#import <UIKit/UIKit.h>

@interface AKSingleSegmentedControl : UISegmentedControl {
}

- (id)initWithItem:(id)item;

@end

AKSingleSegmentedControl.m

#import "AKSingleSegmentedControl.h"

@implementation AKSingleSegmentedControl

- (id)initWithItem:(id)item {
  NSArray *a = [NSArray arrayWithObject:item];
  return [super initWithItems:a];
}

- (void)setSelectedSegmentIndex:(NSInteger)toValue {
  NSInteger newValue = self.selectedSegmentIndex==0 ? -1 : 0;
  [super setSelectedSegmentIndex:newValue];
}

@end