objective-c - 如何给 NSText 多个阴影？

Question

我现在正在用

NSShadow *textShadow = [NSShadow new];
textShadow.shadowBlurRadius = 5;
textShadow.shadowColor = [[NSColor whiteColor] colorWithAlphaComponent:.5];

[self addAttribute:NSShadowAttributeName value:textShadow range:NSMakeRange(0, self.length)];

从 NSTextStorage 给文本一个阴影。但我想应用多个阴影，添加另一个 NSShadowAttributeName 只会覆盖之前的值。

如何添加多个阴影？可以用 CGContextSetShadowWithColor 来完成吗？

Answer 1

不确定请为您的 TextView 尝试下面的代码。当您在 textview 中写入字符串时，它将选择那么大的范围，并在此基础上绘制颜色:-

-(IBAction)createNewTabView:(id)sender
{
   NSString *allTheText =[tv string];
    NSArray *lines = [allTheText componentsSeparatedByString:@"\n"];
    NSString *str=[[NSString alloc]init];
    NSMutableAttributedString *attr;
    BOOL isNext=YES;
    [tv setString:@""];
    for (str in lines)
    {
        attr=[[NSMutableAttributedString alloc]initWithString:str];
        if ([str length] > 0)
        {

        NSRange range=NSMakeRange(0, [str length]);
        [attr addAttribute:NSBackgroundColorAttributeName value:[NSColor greenColor] range:range];
        [tv .textStorage appendAttributedString:attr];
            isNext=YES;
        }
        else
        {
            NSString *str=@"\n";
            NSAttributedString *attr=[[NSAttributedString alloc]initWithString:str];
            [tv .textStorage appendAttributedString:attr];
            isNext=NO;
        }
        if (isNext==YES)
        {
            NSString *str=@"\n";
            NSAttributedString *attr=[[NSAttributedString alloc]initWithString:str];
            [tv .textStorage appendAttributedString:attr];

        }

    }
    }