@alifd/overlay/demo/scroll.md

overlay base component

---
title: 更换弹窗挂载容器
order: 7
---

可以通过 container 把弹窗挂到指定位置，这样性能更好不会一直计算位置，弹窗也不会超出

```jsx
import { useState } from 'react';
import Overlay from '@alifd/overlay';

const { Popup } = Overlay;
const style = {
  width: 500,
  height: 100,
  padding: 10,
  background: '#fff',
  borderRadius: 2,
  boxShadow: '2px 2px 20px rgba(0, 0, 0, 0.15)',
};

const App = () => {
  const [position, setPosition] = useState({});

  return (
    <div
      style={{
        position: 'relative',
        height: 150,
        padding: 30,
        border: '1px solid #eee',
        overflow: 'auto',
      }}
    >
      <Popup
        overlay={
          <div style={style}>
            把节点挂载在父容器下可以避免top一直计算，提高性能: {JSON.stringify(position)}
          </div>
        }
        placement="bl"
        triggerType="click"
        container={(target) => target.parentNode}
        onPosition={({ style }) => {
          setPosition(style);
        }}
      >
        <button style={{ marginTop: 30 }}>Open</button>
      </Popup>
      <div style={{ height: 300, width: 1200 }} />
    </div>
  );
};

ReactDOM.render(<App />, mountNode);
```