同样在你的故事板中，没有一行代码

你可以重写drawPlaceholderInRect:(CGRect)rect来手动渲染占位符文本:

- (void) drawPlaceholderInRect:(CGRect)rect {
    [[UIColor blueColor] setFill];
    [[self placeholder] drawInRect:rect withFont:[UIFont systemFontOfSize:16]];
}

重写drawPlaceholderInRect:将是正确的方式，但由于API(或文档)中的错误，它不起作用。

该方法永远不会在UITextField上被调用。

参见drawTextInRect on UITextField not called

你可以使用digdog的解决方案。因为我不确定这是否通过了苹果的审查，我选择了一个不同的解决方案:用我自己的标签覆盖文本字段，模仿占位符行为。

这有点乱。 代码看起来像这样(注意，我在TextField的子类中这样做):

@implementation PlaceholderChangingTextField

- (void) changePlaceholderColor:(UIColor*)color
{    
    // Need to place the overlay placeholder exactly above the original placeholder
    UILabel *overlayPlaceholderLabel = [[[UILabel alloc] initWithFrame:CGRectMake(self.frame.origin.x + 8, self.frame.origin.y + 4, self.frame.size.width - 16, self.frame.size.height - 8)] autorelease];
    overlayPlaceholderLabel.backgroundColor = [UIColor whiteColor];
    overlayPlaceholderLabel.opaque = YES;
    overlayPlaceholderLabel.text = self.placeholder;
    overlayPlaceholderLabel.textColor = color;
    overlayPlaceholderLabel.font = self.font;
    // Need to add it to the superview, as otherwise we cannot overlay the buildin text label.
    [self.superview addSubview:overlayPlaceholderLabel];
    self.placeholder = nil;
}

此解决方案适用于Swift 4.1

    textName.attributedPlaceholder = NSAttributedString(string: textName.placeholder!, attributes: [NSAttributedStringKey.foregroundColor : UIColor.red])

斯威夫特的版本。也许能帮到别人。

class TextField: UITextField {
   override var placeholder: String? {
        didSet {
            let placeholderString = NSAttributedString(string: placeholder!, attributes: [NSForegroundColorAttributeName: UIColor.whiteColor()])
            self.attributedPlaceholder = placeholderString
        }
    }
}

有了这个，我们可以在iOS中改变文本字段占位符文本的颜色

[self.userNameTxt setValue:[UIColor colorWithRed:41.0/255.0 green:91.0/255.0 blue:106.0/255.0 alpha:1.0] forKeyPath:@"_placeholderLabel.textColor"];