Addon-docs: Fix Preview scaling with transform instead of zoom

lib/components/src/Zoom/Zoom.stories.tsx

@@ -0,0 +1,97 @@
+import React, { CSSProperties, useEffect, useState } from 'react';
+import { Zoom } from './Zoom';
+
+export default {
+  component: Zoom,
+  title: 'Basics/Zoom',
+  argTypes: {
+    scale: {
+      control: { type: 'range', min: 0.2, max: 30, step: 0.02 },
+    },
+  },
+};
+const EXAMPLE_ELEMENT = (
+  <div
+    style={{
+      width: 2000,
+      height: 2000,
+      border: '10px solid orangered',
+      background: `url('data:image/png;base64,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')`,
+    }}
+  />
+);
+
+const TemplateElement = (args) => <Zoom.Element {...args} />;
+
+export const elementActualSize = TemplateElement.bind({});
+
+elementActualSize.args = {
+  scale: 1,
+  children: EXAMPLE_ELEMENT,
+};
+
+export const elementZoomedIn = TemplateElement.bind({});
+
+elementZoomedIn.args = {
+  scale: 0.7,
+  children: EXAMPLE_ELEMENT,
+};
+
+export const elementZoomedOut = TemplateElement.bind({});
+
+elementZoomedOut.args = {
+  scale: 3,
+  children: EXAMPLE_ELEMENT,
+};
+
+const style: CSSProperties = {
+  width: '500px',
+  height: '500px',
+  border: '2px solid hotpink',
+  position: 'relative',
+};
+
+const TemplateIFrame = (args) => {
+  const iFrameRef = React.useRef<HTMLIFrameElement>(null);
+  const [scale, setScale] = useState(1);
+  const [loaded, hasLoaded] = useState(false);
+
+  useEffect(() => {
+    if (loaded) {
+      setScale(args.scale);
+    }
+  }, [args.scale, loaded]);
+  return (
+    <Zoom.IFrame iFrameRef={iFrameRef} scale={scale} active={args.active}>
+      <iframe
+        id="iframe"
+        title="UI Panel"
+        onLoad={() => hasLoaded(true)}
+        src="/iframe.html?id=ui-panel--default&viewMode=story"
+        style={style}
+        ref={iFrameRef}
+        allowFullScreen
+      />
+    </Zoom.IFrame>
+  );
+};
+export const iFrameActualSize = TemplateIFrame.bind({});
+
+iFrameActualSize.args = {
+  scale: 1,
+  active: true,
+};
+
+export const iFrameZoomedIn = TemplateIFrame.bind({});
+
+iFrameZoomedIn.args = {
+  scale: 0.7,
+  active: true,
+};
+
+export const iFrameZoomedOut = TemplateIFrame.bind({});
+
+iFrameZoomedOut.args = {
+  scale: 3,
+  active: true,
+};

lib/components/src/Zoom/Zoom.tsx

@@ -0,0 +1,11 @@
+import window from 'global';
+import { ZoomElement as Element } from './ZoomElement';
+import { ZoomIFrame as IFrame } from './ZoomIFrame';
+
+export const browserSupportsCssZoom = (): boolean =>
+  window.document.implementation.createHTMLDocument().body.style.zoom !== undefined;
+
+export const Zoom = {
+  Element,
+  IFrame,
+};

lib/components/src/Zoom/ZoomElement.tsx

@@ -0,0 +1,40 @@
+import React, { ReactElement, useEffect, useState } from 'react';
+import { styled } from '@storybook/theming';
+import { browserSupportsCssZoom } from './Zoom';
+
+const ZoomElementWrapper = styled.div<{ scale: number; height: number }>(({ scale = 1, height }) =>
+  browserSupportsCssZoom()
+    ? {
+        '> *': {
+          zoom: 1 / scale,
+        },
+      }
+    : {
+        height: height + 50,
+        transformOrigin: 'top left',
+        transform: `scale(${1 / scale})`,
+      }
+);
+type ZoomProps = {
+  scale: number;
+  children: ReactElement | ReactElement[];
+};
+
+export function ZoomElement({ scale, children }: ZoomProps) {
+  const componentWrapperRef = React.useRef<HTMLDivElement>(null);
+  const [height, setHeight] = useState(0);
+
+  useEffect(() => {
+    if (componentWrapperRef.current) {
+      setHeight(componentWrapperRef.current.getBoundingClientRect().height);
+    }
+  }, [scale, componentWrapperRef.current]);
+
+  return (
+    <ZoomElementWrapper scale={scale} height={height}>
+      <div ref={componentWrapperRef} className="innerZoomElementWrapper">
+        {children}
+      </div>
+    </ZoomElementWrapper>
+  );
+}

lib/components/src/Zoom/ZoomIFrame.tsx

@@ -0,0 +1,67 @@
+import { Component, ReactElement } from 'react';
+import { browserSupportsCssZoom } from './Zoom';
+
+export type IZoomIFrameProps = {
+  scale: number;
+  children: ReactElement<HTMLIFrameElement>;
+  iFrameRef: React.MutableRefObject<HTMLIFrameElement>;
+  active?: boolean;
+};
+
+export class ZoomIFrame extends Component<IZoomIFrameProps> {
+  iframe: HTMLIFrameElement = null;
+
+  componentDidMount() {
+    const { iFrameRef } = this.props;
+    this.iframe = iFrameRef.current;
+  }
+
+  shouldComponentUpdate(nextProps: IZoomIFrameProps) {
+    const { scale, active } = this.props;
+
+    if (scale !== nextProps.scale) {
+      this.setIframeInnerZoom(nextProps.scale);
+    }
+
+    if (active !== nextProps.active) {
+      this.iframe.setAttribute('data-is-storybook', nextProps.active ? 'true' : 'false');
+    }
+
+    // this component renders an iframe, which gets updates via post-messages
+    // never update this component, it will cause the iframe to refresh
+    return false;
+  }
+
+  setIframeInnerZoom(scale: number) {
+    try {
+      if (browserSupportsCssZoom()) {
+        Object.assign(this.iframe.contentDocument.body.style, {
+          zoom: 1 / scale,
+        });
+      } else {
+        Object.assign(this.iframe.contentDocument.body.style, {
+          width: `${scale * 100}%`,
+          height: `${scale * 100}%`,
+          transform: `scale(${1 / scale})`,
+          transformOrigin: 'top left',
+        });
+      }
+    } catch (e) {
+      this.setIframeZoom(scale);
+    }
+  }
+
+  setIframeZoom(scale: number) {
+    Object.assign(this.iframe.style, {
+      width: `${scale * 100}%`,
+      height: `${scale * 100}%`,
+      transform: `scale(${1 / scale})`,
+      transformOrigin: 'top left',
+    });
+  }
+
+  render() {
+    const { children } = this.props;
+    return children;
+  }
+}

lib/components/src/blocks/Preview.tsx

@@ -7,6 +7,7 @@ import { Source, SourceProps } from './Source';
 import { ActionBar, ActionItem } from '../ActionBar/ActionBar';
 import { Toolbar } from './Toolbar';
 import { ZoomContext } from './ZoomContext';
+import { Zoom } from '../Zoom/Zoom';
 
 export interface PreviewProps {
   isColumn?: boolean;
@@ -20,15 +21,15 @@ export interface PreviewProps {
 
 type layout = 'padded' | 'fullscreen' | 'centered';
 
-const ChildrenContainer = styled.div<PreviewProps & { zoom: number; layout: layout }>(
+const ChildrenContainer = styled.div<PreviewProps & { layout: layout }>(
   ({ isColumn, columns, layout }) => ({
     display: isColumn || !columns ? 'block' : 'flex',
     position: 'relative',
     flexWrap: 'wrap',
     overflow: 'auto',
     flexDirection: isColumn ? 'column' : 'row',
 
-    '& > *': isColumn
+    '& .innerZoomElementWrapper > *': isColumn
       ? {
           width: layout !== 'fullscreen' ? 'calc(100% - 20px)' : '100%',
           display: 'block',
@@ -43,7 +44,7 @@ const ChildrenContainer = styled.div<PreviewProps & { zoom: number; layout: layo
       ? {
           padding: '30px 20px',
           margin: -10,
-          '& > *': {
+          '& .innerZoomElementWrapper > *': {
             width: 'auto',
             border: '10px solid transparent!important',
           },
@@ -59,13 +60,10 @@ const ChildrenContainer = styled.div<PreviewProps & { zoom: number; layout: layo
           alignItems: 'center',
         }
       : {},
-  ({ zoom = 1 }) => ({
-    '> *': {
-      zoom: 1 / zoom,
-    },
-  }),
   ({ columns }) =>
-    columns && columns > 1 ? { '> *': { minWidth: `calc(100% / ${columns} - 20px)` } } : {}
+    columns && columns > 1
+      ? { '.innerZoomElementWrapper > *': { minWidth: `calc(100% / ${columns} - 20px)` } }
+      : {}
 );
 
 const StyledSource = styled(Source)<{}>(({ theme }) => ({
@@ -217,15 +215,16 @@ const Preview: FunctionComponent<PreviewProps> = ({
           <ChildrenContainer
             isColumn={isColumn || !Array.isArray(children)}
             columns={columns}
-            zoom={scale}
             layout={layout}
           >
-            {Array.isArray(children) ? (
-              // eslint-disable-next-line react/no-array-index-key
-              children.map((child, i) => <div key={i}>{child}</div>)
-            ) : (
-              <div>{children}</div>
-            )}
+            <Zoom.Element scale={scale}>
+              {Array.isArray(children) ? (
+                // eslint-disable-next-line react/no-array-index-key
+                children.map((child, i) => <div key={i}>{child}</div>)
+              ) : (
+                <div>{children}</div>
+              )}
+            </Zoom.Element>
           </ChildrenContainer>
           <ActionBar actionItems={actionItems} />
         </Relative>

lib/components/src/index.ts

@@ -15,6 +15,7 @@ export { ActionBar } from './ActionBar/ActionBar';
 export { Spaced } from './spaced/Spaced';
 export { Placeholder } from './placeholder/placeholder';
 export { ScrollArea } from './ScrollArea/ScrollArea';
+export { Zoom } from './Zoom/Zoom';
 
 // Forms
 export { Button } from './Button/Button';

lib/ui/src/components/preview/iframe.tsx

@@ -1,9 +1,6 @@
-import window from 'global';
-import React, { Component, IframeHTMLAttributes } from 'react';
-
+import React, { IframeHTMLAttributes } from 'react';
 import { styled } from '@storybook/theming';
-
-const FIREFOX_BROWSER = 'Firefox';
+import { Zoom } from '@storybook/components';
 
 const StyledIframe = styled.iframe({
   position: 'absolute',
@@ -25,70 +22,21 @@ export interface IFrameProps {
   active: boolean;
 }
 
-export class IFrame extends Component<IFrameProps & IframeHTMLAttributes<HTMLIFrameElement>> {
-  iframe: HTMLIFrameElement = null;
-
-  componentDidMount() {
-    const { id } = this.props;
-    this.iframe = window.document.getElementById(id);
-  }
-
-  shouldComponentUpdate(nextProps: IFrameProps) {
-    const { scale, active } = this.props;
-
-    if (scale !== nextProps.scale) {
-      this.setIframeInnerZoom(nextProps.scale);
-    }
-
-    if (active !== nextProps.active) {
-      this.iframe.setAttribute('data-is-storybook', nextProps.active ? 'true' : 'false');
-    }
-
-    // this component renders an iframe, which gets updates via post-messages
-    // never update this component, it will cause the iframe to refresh
-    return false;
-  }
-
-  setIframeInnerZoom(scale: number) {
-    try {
-      if (window.navigator.userAgent.indexOf(FIREFOX_BROWSER) !== -1) {
-        Object.assign(this.iframe.contentDocument.body.style, {
-          width: `${scale * 100}%`,
-          height: `${scale * 100}%`,
-          transform: `scale(${1 / scale})`,
-          transformOrigin: 'top left',
-        });
-      } else {
-        Object.assign(this.iframe.contentDocument.body.style, {
-          zoom: 1 / scale,
-        });
-      }
-    } catch (e) {
-      this.setIframeZoom(scale);
-    }
-  }
-
-  setIframeZoom(scale: number) {
-    Object.assign(this.iframe.style, {
-      width: `${scale * 100}%`,
-      height: `${scale * 100}%`,
-      transform: `scale(${1 / scale})`,
-      transformOrigin: 'top left',
-    });
-  }
-
-  render() {
-    const { id, title, src, allowFullScreen, scale, active, ...rest } = this.props;
-    return (
+export function IFrame(props: IFrameProps & IframeHTMLAttributes<HTMLIFrameElement>) {
+  const { active, id, title, src, allowFullScreen, scale, ...rest } = props;
+  const iFrameRef = React.useRef<HTMLIFrameElement>(null);
+  return (
+    <Zoom.IFrame scale={scale} active={active} iFrameRef={iFrameRef}>
       <StyledIframe
-        onLoad={() => this.iframe.setAttribute('data-is-loaded', 'true')}
         data-is-storybook={active ? 'true' : 'false'}
+        onLoad={(e) => e.currentTarget.setAttribute('data-is-loaded', 'true')}
         id={id}
         title={title}
         src={src}
         allowFullScreen={allowFullScreen}
+        ref={iFrameRef}
         {...rest}
       />
-    );
-  }
+    </Zoom.IFrame>
+  );
 }