设置 UISearchBar 输入字体颜色 和 默认字体颜色

UISearchBar *searchBar = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, 210, 44)];

// Get the instance of the UITextField of the search bar
UITextField *searchField = [searchBar valueForKey:@"_searchField"];

// Change search bar text color
searchField.textColor = [UIColor blackColor];

// Change the search bar placeholder text color
[searchField setValue:[UIColor blackColor] forKeyPath:@"_placeholderLabel.textColor"];