Question

我希望通过可拖动的手柄将材料ui抽屉的宽度调整大小。我目前的方法是在整个应用程序上有一个mousevent监听器，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，这需要在整个应用程序上使用一个持续的mouseevent监听器，这对于简单的调整大小功能来说似乎有些过分。

是否有更好/推荐的方法来调整大小？

Answer 1

您可以在其上使用带有mousedown的指标展示器。

这里例如

// 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>

这个想法是，当点击拖动器时，它会在鼠标移动后调整宽度Drawer。

播放DEMO。

Answer 2

只需在handle元素上使用synthetic event即可。这样，您可以避免拥有通用事件侦听器的混乱/性能成本。如下所示：

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

Answer 3

我想使用React Hooks添加最新的答案。

您可以这样操作，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'
}

反应（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>;
}

Answer 4

它可能是一个带有 API 的 useResize 钩子，用于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

然后你可以像这样从你的布局组件中分离调整大小的逻辑：

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>
)

Answer 5

如果符合您的需要，您只能使用css。这是最简单的解决方案。看妈妈，没有javascript。

＆＃13;

.resizable {
  height: 150px;
  width: 150px;
  border: 1px solid #333;
  resize: horizontal;
  overflow: auto;
}

＆＃13;

<div class="resizable"></div>

＆＃13;

Reference on MDN

推荐的方式让抽屉可调整大小？

5 个答案: