在 Angular CLI 应用程序的组件级样式中看不到自定义 Bootstrap 4 断点

media-breakpoint-up在向 $grid-breakpoints 添加新断点后，我在使用 Bootstrap 的mixin声明 scss 样式时遇到问题。

虽然这些d-{infix}-{display}类出现正确并且带有它们的部分工作正常，但组件级 scss 样式没有看到新的断点，尽管导入。

我的问题是 - 我在这里做错了吗？比如进口顺序？

具有这两个依赖项的 Angular CLI 应用程序：

"bootstrap": "^4.1.3",
"ngx-bootstrap": "^3.0.1",

样式.scss

@import 'scss/my.variables';
@import 'scss/my.theme';
@import 'scss/bootstrap.partials';

my.variables.scss（无关紧要）

$brand-primary:#00a651
$fixed-header-min-height: 70px;    
$box-shadow: 0 4px 12px 0 rgba(0, 0, 0, 0.1);
$box-shadow-hover: 0 4px 12px 0 rgba(0, 0, 0, 0.3);

我的主题.scss

$font-family-sans-serif:  proxima-nova, Helvetica, Arial, sans-serif;
$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
$font-family-base:        $font-family-sans-serif;
$font-weight-normal:      200;
$font-weight-base:        $font-weight-normal;
$body-bg:                 #fff;

bootstrap.partials.scss

$grid-breakpoints: (
  xs: 0,
  sm: 576px,
  md: 768px,
  lg: 992px,
  xl: 1200px,
  xxl: 1600px
);

$container-max-widths: (
  sm: 540px,
  md: 720px,
  lg: 960px,
  xl: 1140px,
  xxl: 1540px
);

// Bootstrap partial imports to keep the bloat away
@import '~bootstrap/scss/functions';
@import '~bootstrap/scss/variables';
@import '~bootstrap/scss/mixins';
@import '~bootstrap/scss/reboot';
@import '~bootstrap/scss/type';
@import '~bootstrap/scss/images';
@import '~bootstrap/scss/grid';
@import '~bootstrap/scss/utilities';
@import '~bootstrap/scss/buttons';
@import '~bootstrap/scss/transitions';
@import '~bootstrap/scss/modal';
@import '~bootstrap/scss/close';
@import '~bootstrap/scss/nav';
@import '~bootstrap/scss/navbar';

app.components.html

<h1>Custom breakpoint - xxl introduced (1600px)</h1>

<h2>media queries (media-breakpoint-up et al.)</h2>
<div class="main">
  <p>
    this text should be blue, but red above xxl
  </p>

  <small>
    This Text Should All Be Lowercase, but Uppercase above xxl
  </small>
</div>

<h2>d-* classes</h2>

<p class="d-block">Visible always</p>
<p class="d-none d-lg-block">Visible above lg</p>
<p class="d-none d-xxl-block">Visible above xxl</p>

应用程序组件.scss

@import "~bootstrap/scss/functions";
@import "~bootstrap/scss/variables";
@import '~bootstrap/scss/mixins/_breakpoints';

.main {
  color: blue;
  @debug $grid-breakpoints;

  @include media-breakpoint-up(xxl) {
    /* I have also tried without repeating the selector */
    .main {
      color: red;
    }
  }

  small {
    text-transform: uppercase;
    @include media-breakpoint-up(xxl) {
      small {
        text-transform: lowercase;
      }
    }
  }
}

输出

DEBUG: (xs: 0, sm: 576px, md: 768px, lg: 992px, xl: 1200px)        

没有 xxl。

编辑1：

我创建了一个自定义包装器 mixin，它确认未找到断点。

@mixin respond-above($breakpoint) {
  @if map-has-key($breakpoints, $breakpoint) {
    @include media-breakpoint-up($breakpoint){
      @content;
    }
  } @else {
    @warn 'Missing breakpoint: #{$breakpoint}.';
  }
}