A UIActionSheet subclass that customizes the accessibility labels of the options in the sheet.

FTAccessibleActionSheet.m

// Copyright (c) 2011 Eloy Durán <eloy@fngtps.com>
// Available under the MIT license: http://www.opensource.org/licenses/mit-license.php

#import <objc/message.h>

@interface FTAccessibleActionSheet : UIActionSheet
- (void)copyAccessibilityMetadataFrom:(NSString *)title toControl:(UIView *)control;
@end

@implementation FTAccessibleActionSheet

// When the action sheet is shown with the device in `landscape' mode, it uses
// a table view to show the options. So we override this delegate method which
// gives us the chance to provide the correct accessibility labels.
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {
  // Just to be safe if Apple decides to no longer implement this delegate
  // method in UIActionSheet.
  SEL sel = @selector(tableView:willDisplayCell:forRowAtIndexPath:);
  if ([super respondsToSelector:sel]) {
    struct objc_super target = { self, [self superclass] };
    objc_msgSendSuper(&target, sel, tableView, cell, indexPath);
  }
  // The label seems to always be the last subview, but again let's ensure that
  // this implementation detail does not matter to us.
  for (UIView *view in cell.subviews) {
    if ([view isKindOfClass:[UILabel class]]) {
      [self copyAccessibilityMetadataFrom:[(UILabel *)view text] toControl:view];
      return;
    }
  }
}

- (NSInteger)addButtonWithTitle:(NSString *)title {
  NSInteger i = [super addButtonWithTitle:title];
  // After letting the superclass add the button, search for it by title.
  for (UIView *view in self.subviews) {
    if ([view respondsToSelector:@selector(title)]) {
      NSString *controlTitle = [view performSelector:@selector(title)];
      if ([title isEqualToString:controlTitle]) {
        [self copyAccessibilityMetadataFrom:title toControl:view];
        return i;
      }
    }
  }
  return i;
}

// Copy the actual accessibility data from the title string, which is what UISegmentedControl does.
// 
// For example:
//
//   NSString *title = @"2:3";
//   title.accessibilityLabel = @"two by one";
//   [actionSheet addButtonWithTitle:title];
- (void)copyAccessibilityMetadataFrom:(NSString *)title toControl:(UIView *)control {
  control.accessibilityLanguage = title.accessibilityLanguage;
  control.accessibilityLabel = title.accessibilityLabel;
}

@end