UITextfield不能作为iOS 7中UISearchBar的子视图？

Question

这段代码在iOS 6中工作得很好，但是在iOS 7中，navigationBar中的文本字段为灰色，并且无法单击？ 看到这张图片的区别

可能是什么问题？ 我不知道它们在iOS 7中发生了什么变化，也不确定从哪里开始寻找解决此问题的方法...

/问候

UITextField *sbTextField = (UITextField *)[searchBar.subviews lastObject];
[sbTextField removeFromSuperview];

CGRect rect = searchBar.frame;
rect.size.height = 32;
rect.size.width = 210;
sbTextField.frame = rect;
 // [sbTextField setKeyboardType:UIKeyboardTypeNumbersAndPunctuation]; Not working in iOS7
 // [sbTextField setPlaceholder:NSLocalizedString(@"HintSearchExercise", nil)]; Not working in iOS 7

[sbTextField setAutoresizingMask:UIViewAutoresizingFlexibleBottomMargin];
[searchBar removeFromSuperview];

UIBarButtonItem *searchBarNavigationItem = [[UIBarButtonItem alloc] initWithCustomView:sbTextField];

[[self navigationItem] setLeftBarButtonItem:searchBarNavigationItem];

Answer 1

在ios7中， [searchBar.subviews lastObject] 不是文本字段，而是一个UIView实例，它充当控件周围的附加容器。

与cocktailicious有相同的问题，我计划在UISearchBar上使用以下类别：

@interface UISearchBar (Workarounds)
@property (readonly, nonatomic) UITextField *textField;
@end

@implementation UISearchBar (Workarounds)
- (UITextField *)textField
{
    for (UIView *view in [self subcontrols]) {
        if ([view isKindOfClass:[UITextField class]]) {
            return (UITextField *)view;
        }
    }
    return nil;
}

- (NSArray *)subcontrols
{
    return self.subviews.count == 1 ? [self.subviews.firstObject subviews] : self.subviews;
}
@end

- subcontrols方法在这里起作用。