I found a solution. You can use this for-loop to loop over the subviews of the search bar and enable it when the search button is pressed on the keyboard.
for (UIView *possibleButton in searchBar.subviews)
{
if ([possibleButton isKindOfClass:[UIButton class]])
{
UIButton *cancelButton = (UIButton*)possibleButton;
cancelButton.enabled = YES;
break;
}
}