修改UITextField的placeholder的颜色

第一种

// 文字属性
NSMutableDictionary *attrs = [NSMutableDictionary dictionary];
attrs[NSForegroundColorAttributeName] = [UIColor redColor];

// NSAttributedString : 带有属性的文字(富文本技术)
NSAttributedString *placeholder = [[NSAttributedString alloc] initWithString:@"手机号" attributes:attrs];
self.phoneField.attributedPlaceholder = placeholder;

第二种

   NSMutableAttributedString *placehoder = [[NSMutableAttributedString alloc] initWithString:@"手机号"];
   [placehoder setAttributes:@{NSForegroundColorAttributeName : [UIColor whiteColor]} range:NSMakeRange(0, 1)];
   [placehoder setAttributes:@{
                                NSForegroundColorAttributeName : [UIColor yellowColor],
                                NSFontAttributeName : [UIFont systemFontOfSize:30]
                                } range:NSMakeRange(1, 1)];
   [placehoder setAttributes:@{NSForegroundColorAttributeName : [UIColor redColor]} range:NSMakeRange(2, 1)];
   self.phoneField.attributedPlaceholder = placeholder;

第三种
#import <UIKit/UIKit.h>

@interface XMGTextField : UITextField

@end


- (void)drawPlaceholderInRect:(CGRect)rect
{
[self.placeholder drawInRect:CGRectMake(0, 10, rect.size.width, 25) withAttributes:@{
                                                   NSForegroundColorAttributeName : [UIColor grayColor],
                                                   NSFontAttributeName : self.font}];
}