---
title: fixed dialog
order: 1
---

fixed 模式的dialog，带有遮罩的弹层。

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

const maskStyle = {
  position: 'fixed',
  top: 0,
  right: 0,
  bottom: 0,
  left: 0,
  height: '100%',
  backgroundColor: '#00000073',
};

const Demo = () => {
  const [visible, setVisible] = useState(false);
  const [visible2, setVisible2] = useState(false);

  const dialogRef = useRef(null);

  const onClose = (e) => {
    if (e.type === 'click' && dialogRef.current && dialogRef.current.contains(e.target)) {
      return;
    }
    setVisible(false);
  };

  const onClose2 = (e) => {
    setVisible2(false);
  };

  return (
    <div>
      <button onClick={() => setVisible(true)}> 超出滚动 </button>
      <button onClick={() => setVisible2(true)} style={{ marginLeft: 8 }}>
        {' '}
        内部滚动{' '}
      </button>
      <Overlay
        visible={visible}
        maskClassName="next-overlay-mask"
        maskStyle={maskStyle}
        hasMask
        canCloseByMask
        fixed
        offset={[0, 0]}
        onRequestClose={onClose}
        autoFocus
      >
        <div
          style={{
            position: 'fixed',
            top: 0,
            left: 0,
            bottom: 0,
            right: 0,
            overflow: 'auto',
          }}
          onClick={onClose}
        >
          <div
            style={{
              position: 'relative',
              top: 100,
              width: '100vw',
              pointerEvents: 'none',
              paddingBottom: 24,
            }}
          >
            <div
              role="dialog"
              ref={dialogRef}
              style={{
                pointerEvents: 'auto',
                margin: '0 auto',
                width: 500,
                background: '#fff',
                borderRadius: 2,
                boxShadow:
                  '0 3px 6px -4px #0000001f, 0 6px 16px #00000014, 0 9px 28px 8px #0000000d',
              }}
            >
              with long content
              <br />
              <input />
              <div style={{ padding: '1400px 8px 8px 8px' }}>
                <button onClick={onClose}>ok</button>
                <button onClick={onClose} style={{ marginLeft: 8 }}>
                  cancel
                </button>
              </div>
            </div>
          </div>
        </div>
      </Overlay>

      <Overlay
        visible={visible2}
        maskClassName="next-overlay-mask"
        maskStyle={maskStyle}
        hasMask
        canCloseByMask
        fixed
        autoFocus
        offset={[0, 100]}
        onRequestClose={onClose2}
      >
        <div
          style={{
            position: 'relative',
            width: '100vw',
            pointerEvents: 'none',
          }}
        >
          <div
            role="dialog"
            style={{
              pointerEvents: 'auto',
              margin: '0 auto',
              width: 500,
              maxHeight: 'calc(100vh - 120px)',
              overflow: 'auto',
              background: '#fff',
              borderRadius: 2,
              boxShadow: '0 3px 6px -4px #0000001f, 0 6px 16px #00000014, 0 9px 28px 8px #0000000d',
            }}
          >
            <p>with long content</p>
            <input />
            <div style={{ padding: '1400px 8px 8px 8px' }}>
              <button onClick={onClose}>ok</button>
              <button onClick={onClose} style={{ marginLeft: 8 }}>
                cancel
              </button>
            </div>
          </div>
        </div>
      </Overlay>
    </div>
  );
};

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