# 触发按钮
免费附赠一个触发按钮。
```html
<n-switch v-model="collapsed" />
<n-layout style="height: 240px;">
  <n-layout-header style="height: 64px;">
    酷的页头
  </n-layout-header>
  <n-layout>
    <n-layout-sider
      collapse-mode="width"
      show-trigger
      :collapsed-width="120"
      :width="240"
      :collapsed="collapsed"
      @collapse="collapsed = true"
      @expand="collapsed = false"
    >
      <n-h1>边栏</n-h1>
    </n-layout-sider>
    <n-layout style="padding: 24px;">
      <n-layout-content>
        <span>内容</span>
      </n-layout-content>
      <n-layout-footer>
        <n-h1>页脚</n-h1>
      </n-layout-footer>
    </n-layout>
  </n-layout>
</n-layout>
<n-layout style="height: 240px; overflow: hidden;">
  <n-layout-header position="absolute" style="height: 64px;">
    酷的页头
  </n-layout-header>
  <n-layout position="absolute" style="top: 64px;">
    <n-layout-sider
      position="absolute"
      show-trigger
      collapse-mode="transform"
      :collapsed-width="120"
      :width="240"
      :collapsed="collapsed"
      @collapse="collapsed = true"
      @expand="collapsed = false"
    >
      <n-h1>边栏</n-h1>
    </n-layout-sider>
    <n-layout 
      position="absolute"
      style="padding: 24px;"
    >
      <n-layout-content>
        <span>内容</span>
      </n-layout-content>
      <n-layout-footer>
        <n-h1>页脚</n-h1>
      </n-layout-footer>
    </n-layout>
  </n-layout>
</n-layout>
```
```js
export default {
  data () {
    return {
      collapsed: false
    }
  }
}
```