css - Sass Keyframes 动画混合生成无效的 CSS

Question

我有以下关键帧混合，但它似乎生成了无效的 CSS:

@mixin keyframes($animationName)
{
    @-webkit-keyframes $animationName {
        @content;
    }
    @-moz-keyframes $animationName {
        @content;
    }
    @-o-keyframes $animationName {
        @content;
    }
    @keyframes $animationName {
        @content;
    }
}

@include keyframes(icon-one) {
        0% {
          opacity: 1;
        }
        33% {
          opacity: 0;
        }
        66% {
          opacity: 0;
        }
        100% {
          opacity: 0;
        }
}

这是输出:

@-webkit-keyframes $animationName {
  0% {
    opacity: 1;
  }
  33% {
    opacity: 0;
  }
  66% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@-moz-keyframes $animationName {
  0% {
    opacity: 1;
  }
  33% {
    opacity: 0;
  }
  66% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@-o-keyframes $animationName {
  0% {
    opacity: 1;
  }
  33% {
    opacity: 0;
  }
  66% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@keyframes $animationName {
  0% {
    opacity: 1;
  }
  33% {
    opacity: 0;
  }
  66% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}

它没有使用 icon-one 的关键帧名称，而是写出 $animationName。

Answer 1

您需要对关键帧名称的变量使用字符串插值。你的关键帧 mixin 需要这样写:

@mixin keyframes($animationName)
{
    @-webkit-keyframes #{$animationName} {
        @content;
    }
    @-moz-keyframes #{$animationName}  {
        @content;
    }
    @-o-keyframes #{$animationName} {
        @content;
    }
    @keyframes #{$animationName} {
        @content;
    }
}

请注意 keyframes mixin that comes with Compass does this .

GitHub 上有一个问题表明 interpolation was not required in certain versions of Sass (possibly limited to 3.3.x) .但是，Sass 的作者认为这是一个错误:

The previous behavior was a bug. Variables should never have been allowed uninterpolated in any directives.