Allow EuiDataGrid's default column width to update on resize

CHANGELOG.md

@@ -1,10 +1,12 @@
 ## [`master`](https://github.com/elastic/eui/tree/master)
 
--  Added `prepend` and `append` ability to `EuiComboBox` single selection only ([#3003](https://github.com/elastic/eui/pull/3003))
+- Added `prepend` and `append` ability to `EuiComboBox` single selection only ([#3003](https://github.com/elastic/eui/pull/3003))
+- Added `useResizeObserver` hook ([#2991](https://github.com/elastic/eui/pull/2991))
 
 **Bug Fixes**
 
 - Fixed `EuiFieldNumber` so values of type `number` are now allowed ([#3020](https://github.com/elastic/eui/pull/3020))
+- Fixed bug preventing `EuiDataGrid` from re-evaluating the default column width on resize ([#2991](https://github.com/elastic/eui/pull/2991))
 
 ## [`21.0.0`](https://github.com/elastic/eui/tree/v21.0.0)
 

src-docs/src/views/resize_observer/resize_observer_example.js

@@ -4,16 +4,16 @@ import { renderToHtml } from '../../services';
 
 import { GuideSectionTypes } from '../../components';
 
-import {
-  EuiCode,
-  EuiLink,
-  EuiResizeObserver,
-} from '../../../../src/components';
+import { EuiCode, EuiLink } from '../../../../src/components';
 
 import { ResizeObserverExample as ResizeObserver } from './resize_observer';
 const resizeObserverSource = require('!!raw-loader!./resize_observer');
 const resizeObserverHtml = renderToHtml(ResizeObserver);
 
+import { ResizeObserverHookExample as ResizeObserverHook } from './resize_observer_hook';
+const resizeObserverHookSource = require('!!raw-loader!./resize_observer_hook');
+const resizeObserverHookHtml = renderToHtml(ResizeObserverHook);
+
 export const ResizeObserverExample = {
   title: 'ResizeObserver',
   sections: [
@@ -57,8 +57,29 @@ export const ResizeObserverExample = {
           </p>
         </React.Fragment>
       ),
-      components: { EuiResizeObserver },
       demo: <ResizeObserver />,
     },
+    {
+      title: 'useResizeObserver hook',
+      source: [
+        {
+          type: GuideSectionTypes.JS,
+          code: resizeObserverHookSource,
+        },
+        {
+          type: GuideSectionTypes.HTML,
+          code: resizeObserverHookHtml,
+        },
+      ],
+      text: (
+        <React.Fragment>
+          <p>
+            There is also a React hook, <EuiCode>useResizeObserver</EuiCode>,
+            which provides the same observation functionality.
+          </p>
+        </React.Fragment>
+      ),
+      demo: <ResizeObserverHook />,
+    },
   ],
 };

src-docs/src/views/resize_observer/resize_observer_hook.js

@@ -0,0 +1,72 @@
+import React, { useRef, useState } from 'react';
+
+import {
+  EuiButton,
+  EuiButtonEmpty,
+  EuiCode,
+  EuiIcon,
+  EuiPanel,
+  EuiSpacer,
+  EuiText,
+  useResizeObserver,
+} from '../../../../src/components';
+
+export const ResizeObserverHookExample = () => {
+  const hasResizeObserver = typeof ResizeObserver !== 'undefined';
+  const [paddingSize, setPaddingSize] = useState('s');
+  const [items, setItems] = useState(['Item 1', 'Item 2', 'Item 3']);
+
+  const togglePaddingSize = () => {
+    setPaddingSize(paddingSize => (paddingSize === 's' ? 'l' : 's'));
+  };
+
+  const addItem = () => {
+    setItems(items => [...items, `Item ${items.length + 1}`]);
+  };
+
+  const resizeRef = useRef();
+  const dimensions = useResizeObserver(resizeRef.current);
+
+  return (
+    <div>
+      <EuiText>
+        {hasResizeObserver ? (
+          <p>
+            <EuiIcon type="checkInCircleFilled" color="secondary" /> Browser
+            supports ResizeObserver API.
+          </p>
+        ) : (
+          <p>
+            <EuiIcon type="crossInACircleFilled" color="danger" /> Browser does
+            not support ResizeObserver API. Using MutationObserver.
+          </p>
+        )}
+        <p>
+          <EuiCode>{`height: ${dimensions.height}; width: ${
+            dimensions.width
+          }`}</EuiCode>
+        </p>
+      </EuiText>
+
+      <EuiSpacer />
+
+      <EuiButton fill={true} onClick={togglePaddingSize}>
+        Toggle container padding
+      </EuiButton>
+
+      <EuiSpacer />
+
+      <div className="eui-displayInlineBlock" ref={resizeRef}>
+        <EuiPanel className="eui-displayInlineBlock" paddingSize={paddingSize}>
+          <ul>
+            {items.map(item => (
+              <li key={item}>{item}</li>
+            ))}
+          </ul>
+          <EuiSpacer size="s" />
+          <EuiButtonEmpty onClick={addItem}>add item</EuiButtonEmpty>
+        </EuiPanel>
+      </div>
+    </div>
+  );
+};

src/components/datagrid/data_grid.tsx

@@ -55,6 +55,7 @@ import {
 import { useColumnSorting } from './column_sorting';
 import { EuiMutationObserver } from '../observer/mutation_observer';
 import { DataGridContext } from './data_grid_context';
+import { useResizeObserver } from '../observer/resize_observer/resize_observer';
 
 // When below this number the grid only shows the full screen button
 const MINIMUM_WIDTH_FOR_GRID_CONTROLS = 479;
@@ -225,40 +226,40 @@ function useDefaultColumnWidth(
   trailingControlColumns: EuiDataGridProps['leadingControlColumns'] = [],
   columns: EuiDataGridProps['columns']
 ): number | null {
+  const containerSize = useResizeObserver(container);
+
   const [defaultColumnWidth, setDefaultColumnWidth] = useState<number | null>(
     null
   );
 
   useEffect(() => {
-    if (container != null) {
-      const gridWidth = container.clientWidth;
-
-      const controlColumnWidths = [
-        ...leadingControlColumns,
-        ...trailingControlColumns,
-      ].reduce<number>(
-        (claimedWidth, controlColumn: EuiDataGridControlColumn) =>
-          claimedWidth + controlColumn.width,
-        0
-      );
+    const gridWidth = containerSize.width;
+
+    const controlColumnWidths = [
+      ...leadingControlColumns,
+      ...trailingControlColumns,
+    ].reduce<number>(
+      (claimedWidth, controlColumn: EuiDataGridControlColumn) =>
+        claimedWidth + controlColumn.width,
+      0
+    );
 
-      const columnsWithWidths = columns.filter<
-        EuiDataGridColumn & { initialWidth: number }
-      >(doesColumnHaveAnInitialWidth);
+    const columnsWithWidths = columns.filter<
+      EuiDataGridColumn & { initialWidth: number }
+    >(doesColumnHaveAnInitialWidth);
 
-      const definedColumnsWidth = columnsWithWidths.reduce(
-        (claimedWidth, column) => claimedWidth + column.initialWidth,
-        0
-      );
+    const definedColumnsWidth = columnsWithWidths.reduce(
+      (claimedWidth, column) => claimedWidth + column.initialWidth,
+      0
+    );
 
-      const claimedWidth = controlColumnWidths + definedColumnsWidth;
+    const claimedWidth = controlColumnWidths + definedColumnsWidth;
 
-      const widthToFill = gridWidth - claimedWidth;
-      const unsizedColumnCount = columns.length - columnsWithWidths.length;
-      const columnWidth = Math.max(widthToFill / unsizedColumnCount, 100);
-      setDefaultColumnWidth(columnWidth);
-    }
-  }, [container, columns, leadingControlColumns, trailingControlColumns]);
+    const widthToFill = gridWidth - claimedWidth;
+    const unsizedColumnCount = columns.length - columnsWithWidths.length;
+    const columnWidth = Math.max(widthToFill / unsizedColumnCount, 100);
+    setDefaultColumnWidth(columnWidth);
+  }, [containerSize, columns, leadingControlColumns, trailingControlColumns]);
 
   return defaultColumnWidth;
 }

src/components/datagrid/data_grid_cell.tsx

@@ -150,6 +150,7 @@ export class EuiDataGridCell extends Component<
     if (nextProps.visibleRowIndex !== this.props.visibleRowIndex) return true;
     if (nextProps.colIndex !== this.props.colIndex) return true;
     if (nextProps.columnId !== this.props.columnId) return true;
+    if (nextProps.columnType !== this.props.columnType) return true;
     if (nextProps.width !== this.props.width) return true;
     if (nextProps.renderCellValue !== this.props.renderCellValue) return true;
     if (nextProps.onCellFocus !== this.props.onCellFocus) return true;

src/components/index.js

@@ -239,7 +239,10 @@ export { EuiProgress } from './progress';
 
 export { EuiTreeView } from './tree_view';
 
-export { EuiResizeObserver } from './observer/resize_observer';
+export {
+  EuiResizeObserver,
+  useResizeObserver,
+} from './observer/resize_observer';
 
 export { EuiSearchBar, Query, Ast } from './search_bar';
 

src/components/observer/observer.ts

@@ -4,7 +4,7 @@ interface BaseProps {
   children: (ref: any) => ReactNode;
 }
 
-interface Observer {
+export interface Observer {
   disconnect: () => void;
   observe: (element: Element, options?: { [key: string]: any }) => void;
 }

src/components/observer/resize_observer/index.ts

@@ -1 +1 @@
-export { EuiResizeObserver } from './resize_observer';
+export { EuiResizeObserver, useResizeObserver } from './resize_observer';

src/components/observer/resize_observer/resize_observer.test.tsx

@@ -1,7 +1,8 @@
-import React, { FunctionComponent } from 'react';
+import React, { FunctionComponent, useState } from 'react';
 import { mount } from 'enzyme';
-import { EuiResizeObserver } from './resize_observer';
+import { EuiResizeObserver, useResizeObserver } from './resize_observer';
 import { sleep } from '../../../test';
+import { act } from 'react-dom/test-utils';
 
 export async function waitforResizeObserver(period = 30) {
   // `period` defaults to 30 because its the delay used by the ResizeObserver polyfill
@@ -10,7 +11,7 @@ export async function waitforResizeObserver(period = 30) {
 
 describe('EuiResizeObserver', () => {
   it('watches for a resize', async () => {
-    expect.assertions(1);
+    expect.assertions(2);
     const onResize = jest.fn();
 
     const Wrapper: FunctionComponent<{}> = ({ children }) => {
@@ -25,6 +26,10 @@ describe('EuiResizeObserver', () => {
 
     const component = mount(<Wrapper children={<div>Hello World</div>} />);
 
+    // Resize observer is expected to fire once on mount
+    await waitforResizeObserver();
+    expect(onResize).toHaveBeenCalledTimes(1);
+
     component.setProps({
       children: (
         <div>
@@ -40,3 +45,35 @@ describe('EuiResizeObserver', () => {
     expect(onResize).toHaveBeenCalledTimes(2);
   });
 });
+
+describe('useResizeObserver', () => {
+  it('watches for a resize', async () => {
+    expect.assertions(2);
+
+    const Wrapper: FunctionComponent<{}> = jest.fn(({ children }) => {
+      const [ref, setRef] = useState();
+      useResizeObserver(ref);
+      return <div ref={setRef}>{children}</div>;
+    });
+
+    const component = mount(<Wrapper children={<div>Hello World</div>} />);
+
+    // Expect the initial render, re-render when the ref is created, and a 3rd for the onresize callback
+    await act(() => waitforResizeObserver());
+    expect(Wrapper).toHaveBeenCalledTimes(3);
+
+    component.setProps({
+      children: (
+        <div>
+          <div>Hello World</div>
+          <div>Hello Again</div>
+        </div>
+      ),
+    });
+
+    await waitforResizeObserver();
+
+    // Expect two more calls because children changed (re-render) & resize observer rected
+    expect(Wrapper).toHaveBeenCalledTimes(5);
+  });
+});