使抽屉可调整大小的推荐方法?

Recommended way to have drawer resizable?

我希望 material ui 抽屉的宽度可以通过可拖动的手柄调整大小。 我目前的方法是在整个应用程序上有一个 mousevent 侦听器,它检查是否按下了句柄并根据每次鼠标移动时的鼠标位置更新宽度。

然而,这需要ui在整个应用程序上设置一个恒定的鼠标事件侦听器,这对于一个简单的调整大小功能来说似乎有点过分了。

是否有更好/推荐的调整大小方法?

只需在句柄元素上使用 synthetic event。这样,您就可以避免使用通用事件侦听器的 messiness/performance 成本。类似于以下内容:

render() {
     return (
       <div onMouseDown={this.yourResizeFunc}>
       </div>
  );
}

如果满足您的需要,您可以只使用 css 来做到这一点。这是最简单的解决方案。妈妈你看,没有javascript.

.resizable {
  height: 150px;
  width: 150px;
  border: 1px solid #333;
  resize: horizontal;
  overflow: auto;
}
<div class="resizable"></div>

Reference on MDN

您可以使用带有 mousedown 的指标拖动器。

这里举例

// styles
dragger: {
  width: '5px',
  cursor: 'ew-resize',
  padding: '4px 0 0',
  borderTop: '1px solid #ddd',
  position: 'absolute',
  top: 0,
  left: 0,
  bottom: 0,
  zIndex: '100',
  backgroundColor: '#f4f7f9'
}

...

state = {
  isResizing: false,
  lastDownX: 0,
  newWidth: {}
};

handleMousedown = e => {
  this.setState({ isResizing: true, lastDownX: e.clientX });
};

handleMousemove = e => {
  // we don't want to do anything if we aren't resizing.
  if (!this.state.isResizing) {
    return;
  }

  let offsetRight =
    document.body.offsetWidth - (e.clientX - document.body.offsetLeft);
  let minWidth = 50;
  let maxWidth = 600;
  if (offsetRight > minWidth && offsetRight < maxWidth) {
    this.setState({ newWidth: { width: offsetRight } });
  }
};

handleMouseup = e => {
  this.setState({ isResizing: false });
};

componentDidMount() {
  document.addEventListener('mousemove', e => this.handleMousemove(e));
  document.addEventListener('mouseup', e => this.handleMouseup(e));
}

...

<Drawer
  variant="permanent"
  open
  anchor={'right'}
  classes={{
    paper: classes.drawerPaper
  }}
  PaperProps={{ style: this.state.newWidth }}
>
  <div
    id="dragger"
    onMouseDown={event => {
      this.handleMousedown(event);
    }}
    className={classes.dragger}
  />
  {drawer}
</Drawer>

想法是,当单击拖动器时,它会随着鼠标移动调整宽度 Drawer

播放DEMO.

我想添加一个使用 React Hooks 的最新答案。

你可以这样做,然后:

CSS:

sidebar-dragger: {
  width: '5px',
  cursor: 'ew-resize',
  padding: '4px 0 0',
  borderTop: '1px solid #ddd',
  position: 'absolute',
  top: 0,
  left: 0,
  bottom: 0,
  zIndex: '100',
  backgroundColor: '#f4f7f9'
}

React(使用带有引用和状态的钩子)

let isResizing = null;

function ResizeableSidebar (props) {
  const sidebarPanel = React.useRef('sidebarPanel');
  const cbHandleMouseMove = React.useCallback(handleMousemove, []);
  const cbHandleMouseUp = React.useCallback(handleMouseup, []);

  function handleMousedown (e) {
    e.stopPropagation();
    e.preventDefault();
    // we will only add listeners when needed, and remove them afterward
    document.addEventListener('mousemove', cbHandleMouseMove);
    document.addEventListener('mouseup', cbHandleMouseUp);
    isResizing = true;
  };

  function handleMousemove (e) {
    if (!isResizing) {
      return;
    }

    let offsetRight =
      document.body.offsetWidth - (e.clientX - document.body.offsetLeft);
    let minWidth = 50;
    if (offsetRight > minWidth) {
      let curSize = offsetRight - 60;
      // using a ref instead of state will be way faster
      sidebarPanel.current.style.width = curSize + 'px';
    }
  };

  function handleMouseup (e) {
    if (!isResizing) {
      return;
    }
    isResizing = false;
    document.removeEventListener('mousemove', cbHandleMouseMove);
    document.removeEventListener('mouseup', cbHandleMouseUp);
  };

  return <div className="sidebar-container">
    <div
      className="sidebar-dragger"
      onMouseDown={handleMousedown}
    />
    <div>
      Your stuff goes here
    </div>
  </div>;
}

它可能是一个 useResize 挂钩 API 以启用调整大小和提供当前宽度。

import { useCallback, useEffect, useState } from 'react'

type UseResizeProps = {
  minWidth: number
}

type UseResizeReturn = {
  width: number
  enableResize: () => void
}

const useResize = ({
  minWidth,
}: UseResizeProps): UseResizeReturn => {
  const [isResizing, setIsResizing] = useState(false)
  const [width, setWidth] = useState(minWidth)

  const enableResize = useCallback(() => {
    setIsResizing(true)
  }, [setIsResizing])

  const disableResize = useCallback(() => {
    setIsResizing(false)
  }, [setIsResizing])

  const resize = useCallback(
    (e: MouseEvent) => {
      if (isResizing) {
        const newWidth = e.clientX // You may want to add some offset here from props
        if (newWidth >= minWidth) {
          setWidth(newWidth)
        }
      }
    },
    [minWidth, isResizing, setWidth],
  )

  useEffect(() => {
    document.addEventListener('mousemove', resize)
    document.addEventListener('mouseup', disableResize)

    return () => {
      document.removeEventListener('mousemove', resize)
      document.removeEventListener('mouseup', disableResize)
    }
  }, [disableResize, resize])

  return { width, enableResize }
}

export default useResize

然后您可以像这样将调整大小逻辑与布局组件分离:

const Layout = () => {
  const { width, enableResize } = useResize(200);

  return (
    <Drawer
      variant="permanent"
      open
      PaperProps={{ style: { width } }}
    >
      {drawer}
      <div
        style={{ 
          position: absolute,
          width: '2px',
          top: '0',
          right: '-1px',
          bottom: '0',
          cursor: 'col-resize'
        }}
        onMouseDown={enableResize}
      />
    </Drawer>
)