使弹性项目在一行中具有相等的宽度

Question

在下面的示例中，我希望标头 ( h4.child-title ) 在父容器中具有相同的长度。

但我没有成功实现这一目标。

 .top-level {
  display: flex;
  flex-flow: row wrap;
}

.section {
  display: flex;
  flex-flow: row nowrap;
  border: 1px solid;
  margin-right: 12px;
  margin-top: 12px;
}

.section-child {
  display: flex;
  flex-flow: column nowrap;
  align-items: center;
  flex: 1 1 0;
}

.child-title {
  white-space: nowrap;
}

.vertical-separator {
  width: 1px;
  background-color: rgba(0, 0, 0, 0.3);
  margin: 8px;
}

 <div class="top-level">
  <section class="section">
    <div claas="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div claas="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div claas="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
</div>

原文由 Ashok Koyi 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

弹性盒方法

为了使文本项 ( .section-child ) 等宽，您需要使用 flex: 1 1 0 ，您已经完成了。这与说 flex: 1 是一样的。

但是，这本身并不能实现目标，原因有二：

1. .section-child 的父级，一个 flex 容器，也是一个更大容器中的 flex 项目，默认情况下限制为其内容的宽度。所以它不会展开并且文本会溢出容器。您还需要将 flex: 1 应用到 .section 。

2. 默认情况下，弹性项目不能小于其内容的大小。初始设置为 min-width: auto 。所以 flex: 1 不能平均分配容器空间，因为弹性项目不能收缩超过最长的项目。您需要使用 min-width: 0 覆盖此行为。

 .top-level {
  display: flex;
  flex-flow: row wrap;
}

.section {
  display: flex;
  flex-flow: row nowrap;
  border: 1px solid;
  margin-right: 12px;
  margin-top: 12px;
  flex: 1;
  min-width: 0;
}

.section-child {
  display: flex;
  flex-flow: column nowrap;
  align-items: center;
  flex: 1;
  min-width: 0;
}

.child-title {
  white-space: nowrap;
}

.vertical-separator {
  width: 1px;
  background-color: rgba(0, 0, 0, 0.3);
  margin: 8px;
}

 <div class="top-level">
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
</div>

现在所有的弹性项目都是等宽的。但是，因为您将文本设置为 nowrap ，它可能会溢出其边界。如果你删除 nowrap ，一切都很合适。

 .top-level {
  display: flex;
  flex-flow: row wrap;
}

.section {
  display: flex;
  flex-flow: row nowrap;
  border: 1px solid;
  margin-right: 12px;
  margin-top: 12px;
  flex: 1;
  min-width: 0;
}

.section-child {
  display: flex;
  flex-flow: column nowrap;
  align-items: center;
  flex: 1;
  min-width: 0;
}

.child-title {
  /* white-space: nowrap; */
}

.vertical-separator {
  width: 1px;
  background-color: rgba(0, 0, 0, 0.3);
  margin: 8px;
}

 <div class="top-level">
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
</div>

更多信息：

• 使 flex-grow 扩展项目基于其原始大小
• 为什么弹性项目不会缩小过去的内容大小？

---

CSS 网格方法

如果您的实际目标是使行中的所有弹性项目等于最长项目的宽度，那是 flexbox 无法做到的。

flex可以做等宽等高的flex items，因为它在主轴上提供了 flex: 1 。

Flex也可以做等宽等高的列/行，因为它在横轴上提供了 align-items: stretch 。

但是 flexbox 规范中没有关于基于特定兄弟大小的相等大小 flex 项目的任何内容。但是，flexbox 的姊妹技术 CSS Grid 可以做到。

通过使用 Grid 的 fr 单元，可以将网格中的列宽设置为最长列的宽度。

 .top-level {
  display: flex;
  flex-flow: row wrap;
}

.section {
  display: grid;
  grid-template-columns: 1fr 1px 1fr 1px 1fr;
  margin-right: 12px;
  margin-top: 12px;
}

.section-child {
  display: flex;
  justify-content: center;
  align-items: center;
  min-width: 0;
  background-color: green;
}

.child-title {
  /* white-space: nowrap; */
}

.vertical-separator {
  background-color: rgba(0, 0, 0, 0.3);
  margin: 8px;
}

 <div class="top-level">
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title text text text text text text text text text text</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title text text text text text text</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="vertical-separator"></div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
</div>

它是这样工作的：

• CSS 网格布局中的等高行

原文由 Michael Benjamin 发布，翻译遵循 CC BY-SA 3.0 许可协议

Answer 2

Flexbox 不是表格类布局的完美选择，但你可以接近：

• 添加 flex: 1 1 100% 到 sectionchild ，它会同样缩小（或增长），基于设置为 100%

• 添加 overflow: hidden 或 min-width ，告诉 section-child 它们可以小于它们的内容

• add flex-basis: 100% , or flex-grow: 1 , to section and it will take full with of its parent, the top-level

As vertical-separator , I instead used a pseudo ::after on every section-child but the first, and since it use absolute position, position: relative is needed在 section-child 上。

 .top-level {
  display: flex;
  flex-flow: row wrap;
}

.section {
  flex-basis: 100%;              /*  added  */
  display: flex;
  flex-flow: row nowrap;
  border: 1px solid;
  margin-right: 12px;
  margin-top: 12px;
}

.section-child {
  position: relative;             /*  added  */
  display: flex;
  flex-flow: column nowrap;
  align-items: center;
  flex: 1 1 100%;                 /*  added  */
  overflow: hidden;               /*  added  */
}

.child-title {
  white-space: nowrap;
}

.section-child + .section-child::after {
  content: '';
  position: absolute;
  left: 0;
  top: 10%;
  height: 80%;
  border-left: 1px solid rgba(0,0,0,0.3);
}

 <div class="top-level">
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
  <section class="section">
    <div class="section-child">
      <h4 class="child-title">Title</h4>
      <!--A lot more content here-->
    </div>
    <div class="section-child">
      <h4 class="child-title">Longer title</h4>
      <!--A lot more content here-->
    </div>
    <div class="section-child">
      <h4 class="child-title">Much much longer title</h4>
      <!--A lot more content here-->
    </div>
  </section>
</div>

原文由 Asons 发布，翻译遵循 CC BY-SA 3.0 许可协议