grafana/public/app/core/components/Page/Page.tsx

// Libraries
import { css, cx } from '@emotion/css';
import React, { useLayoutEffect } from 'react';

import { GrafanaTheme2, PageLayoutType } from '@grafana/data';
import { CustomScrollbar, useStyles2 } from '@grafana/ui';
import { useGrafana } from 'app/core/context/GrafanaContext';

import { PageContents } from './PageContents';
import { PageHeader } from './PageHeader';
import { PageTabs } from './PageTabs';
import { PageType } from './types';
import { usePageNav } from './usePageNav';
import { usePageTitle } from './usePageTitle';

export const Page: PageType = ({
  navId,
  navModel: oldNavProp,
  pageNav,
  renderTitle,
  onEditTitle,
  actions,
  subTitle,
  children,
  className,
  info,
  layout = PageLayoutType.Standard,
  scrollTop,
  scrollRef,
  ...otherProps
}) => {
  const styles = useStyles2(getStyles);
  const navModel = usePageNav(navId, oldNavProp);
  const { chrome } = useGrafana();

  usePageTitle(navModel, pageNav);

  const pageHeaderNav = pageNav ?? navModel?.node;

  // We use useLayoutEffect here to make sure that the chrome is updated before the page is rendered
  // This prevents flickering sectionNav when going from dashboard to settings for example
  useLayoutEffect(() => {
    if (navModel) {
      chrome.update({
        sectionNav: navModel,
        pageNav: pageNav,
        layout: layout,
      });
    }
  }, [navModel, pageNav, chrome, layout]);

  return (
    <div className={cx(styles.wrapper, className)} {...otherProps}>
      {layout === PageLayoutType.Standard && (
        <CustomScrollbar autoHeightMin={'100%'} scrollTop={scrollTop} scrollRefCallback={scrollRef}>
          <div className={styles.pageInner}>
            {pageHeaderNav && (
              <PageHeader
                actions={actions}
                onEditTitle={onEditTitle}
                navItem={pageHeaderNav}
                renderTitle={renderTitle}
                info={info}
                subTitle={subTitle}
              />
            )}
            {pageNav && pageNav.children && <PageTabs navItem={pageNav} />}
            <div className={styles.pageContent}>{children}</div>
          </div>
        </CustomScrollbar>
      )}
      {layout === PageLayoutType.Canvas && (
        <CustomScrollbar autoHeightMin={'100%'} scrollTop={scrollTop} scrollRefCallback={scrollRef}>
          <div className={styles.canvasContent}>{children}</div>
        </CustomScrollbar>
      )}
      {layout === PageLayoutType.Custom && children}
    </div>
  );
};

Page.Contents = PageContents;

const getStyles = (theme: GrafanaTheme2) => {
  return {
    wrapper: css({
      label: 'page-wrapper',
      height: '100%',
      display: 'flex',
      flex: '1 1 0',
      flexDirection: 'column',
      minHeight: 0,
    }),
    pageContent: css({
      label: 'page-content',
      flexGrow: 1,
    }),
    pageInner: css({
      label: 'page-inner',
      padding: theme.spacing(2),
      borderBottom: 'none',
      background: theme.colors.background.primary,
      display: 'flex',
      flexDirection: 'column',
      flexGrow: 1,
      margin: theme.spacing(0, 0, 0, 0),

      [theme.breakpoints.up('md')]: {
        padding: theme.spacing(4),
      },
    }),
    canvasContent: css({
      label: 'canvas-content',
      display: 'flex',
      flexDirection: 'column',
      padding: theme.spacing(2),
      flexBasis: '100%',
      flexGrow: 1,
    }),
  };
};