替换SearchBar 键盘上的 搜索 按钮

for (UIView *searchBarSubview in [searchBar subviews])

{

       if ([searchBarSubview conformsToProtocol:@protocol(UITextInputTraits)])

　　　　{

               [(UITextField *)searchBarSubview setReturnKeyType:UIReturnKeyDone];

               [(UITextField *)searchBarSubview setEnablesReturnKeyAutomatically:NO];

       }

}