chore: Watermark uses MutateObserver (#40081)

* chore: Watermark uses MutateObserver

* chore: upgrade @rc-component/mutate-observer

components/watermark/__tests__/index.test.tsx

@@ -2,7 +2,7 @@ import React from 'react';
 import Watermark from '..';
 import mountTest from '../../../tests/shared/mountTest';
 import rtlTest from '../../../tests/shared/rtlTest';
-import { render, waitFor } from '../../../tests/utils';
+import { render, waitFor, waitFakeTimer } from '../../../tests/utils';
 
 describe('Watermark', () => {
   mountTest(Watermark);
@@ -67,6 +67,7 @@ describe('Watermark', () => {
   it('MutationObserver should work properly', async () => {
     const { container } = render(<Watermark className="watermark" content="MutationObserver" />);
     const target = container.querySelector<HTMLDivElement>('.watermark div');
+    await waitFakeTimer();
     target?.remove();
     await waitFor(() => expect(target).toBeTruthy());
     expect(container).toMatchSnapshot();
@@ -77,6 +78,7 @@ describe('Watermark', () => {
       <Watermark offset={[-200, -200]} className="watermark" content="MutationObserver" />,
     );
     const target = container.querySelector<HTMLDivElement>('.watermark div');
+    await waitFakeTimer();
     target?.setAttribute('style', '');
     await waitFor(() => expect(target).toBeTruthy());
     expect(container).toMatchSnapshot();

components/watermark/index.tsx

@@ -1,6 +1,6 @@
 import React, { useEffect, useRef } from 'react';
-import useMutationObserver from './useMutationObserver';
+import MutateObserver from '@rc-component/mutate-observer';
-import { getStyleStr, getPixelRatio, rotateWatermark } from './utils';
+import { getStyleStr, getPixelRatio, rotateWatermark, reRendering } from './utils';
 
 /**
  * Base size of the canvas, 1 for parallel layout and 2 for alternate layout
@@ -96,7 +96,7 @@ const Watermark: React.FC<WatermarkProps> = (props) => {
 
   const containerRef = useRef<HTMLDivElement>(null);
   const watermarkRef = useRef<HTMLDivElement>();
-  const { createObserver, destroyObserver, reRendering } = useMutationObserver();
+  const stopObservation = useRef(false);
 
   const destroyWatermark = () => {
     if (watermarkRef.current) {
@@ -107,7 +107,7 @@ const Watermark: React.FC<WatermarkProps> = (props) => {
 
   const appendWatermark = (base64Url: string, markWidth: number) => {
     if (containerRef.current && watermarkRef.current) {
-      destroyObserver();
+      stopObservation.current = true;
       watermarkRef.current.setAttribute(
         'style',
         getStyleStr({
@@ -117,14 +117,9 @@ const Watermark: React.FC<WatermarkProps> = (props) => {
         }),
       );
       containerRef.current?.append(watermarkRef.current);
-      createObserver(containerRef.current, (mutations) => {
+      // Delayed execution
-        mutations.forEach((mutation) => {
+      setTimeout(() => {
-          if (reRendering(mutation, watermarkRef.current)) {
+        stopObservation.current = false;
-            destroyWatermark();
-            // eslint-disable-next-line @typescript-eslint/no-use-before-define
-            renderWatermark();
-          }
-        });
       });
     }
   };
@@ -221,6 +216,18 @@ const Watermark: React.FC<WatermarkProps> = (props) => {
     }
   };
 
+  const onMutate = (mutations: MutationRecord[]) => {
+    if (stopObservation.current) {
+      return;
+    }
+    mutations.forEach((mutation) => {
+      if (reRendering(mutation, watermarkRef.current)) {
+        destroyWatermark();
+        renderWatermark();
+      }
+    });
+  };
+
   useEffect(renderWatermark, [
     rotate,
     zIndex,
@@ -240,9 +247,11 @@ const Watermark: React.FC<WatermarkProps> = (props) => {
   ]);
 
   return (
+    <MutateObserver onMutate={onMutate}>
       <div ref={containerRef} className={className} style={{ position: 'relative', ...style }}>
         {children}
       </div>
+    </MutateObserver>
   );
 };
 

components/watermark/useMutationObserver.ts

@@ -1,42 +0,0 @@
-import { useEffect, useRef } from 'react';
-
-export default function useMutationObserver() {
-  const instance = useRef<MutationObserver>();
-
-  const destroyObserver = () => {
-    if (instance.current) {
-      instance.current.takeRecords();
-      instance.current.disconnect();
-      instance.current = undefined;
-    }
-  };
-
-  const createObserver = (target: Node, callback: MutationCallback) => {
-    if (MutationObserver) {
-      destroyObserver();
-      instance.current = new MutationObserver(callback);
-      instance.current.observe(target, {
-        childList: true,
-        subtree: true,
-        attributeFilter: ['style', 'class'],
-      });
-    }
-  };
-
-  useEffect(() => destroyObserver, []);
-
-  const reRendering = (mutation: MutationRecord, watermarkElement?: HTMLElement) => {
-    let flag = false;
-    // Whether to delete the watermark node
-    if (mutation.removedNodes.length) {
-      flag = Array.from(mutation.removedNodes).some((node) => node === watermarkElement);
-    }
-    // Whether the watermark dom property value has been modified
-    if (mutation.type === 'attributes' && mutation.target === watermarkElement) {
-      flag = true;
-    }
-    return flag;
-  };
-
-  return { createObserver, destroyObserver, reRendering };
-}

components/watermark/utils.ts

@@ -25,3 +25,17 @@ export function rotateWatermark(
   ctx.rotate((Math.PI / 180) * Number(rotate));
   ctx.translate(-rotateX, -rotateY);
 }
+
+/** Whether to re-render the watermark */
+export const reRendering = (mutation: MutationRecord, watermarkElement?: HTMLElement) => {
+  let flag = false;
+  // Whether to delete the watermark node
+  if (mutation.removedNodes.length) {
+    flag = Array.from(mutation.removedNodes).some((node) => node === watermarkElement);
+  }
+  // Whether the watermark dom property value has been modified
+  if (mutation.type === 'attributes' && mutation.target === watermarkElement) {
+    flag = true;
+  }
+  return flag;
+};

package.json

@@ -113,6 +113,7 @@
     "@ant-design/react-slick": "~1.0.0",
     "@babel/runtime": "^7.18.3",
     "@ctrl/tinycolor": "^3.4.0",
+    "@rc-component/mutate-observer": "^1.0.0",
     "@rc-component/tour": "~1.1.0",
     "classnames": "^2.2.6",
     "copy-to-clipboard": "^3.2.0",