[DataGrid] Add touch support on column resize

packages/grid/_modules_/grid/components/styled-wrappers/GridRootStyles.ts

@@ -124,7 +124,15 @@ export const useStyles = makeStyles(
         },
         '& .MuiDataGrid-columnSeparatorResizable': {
           cursor: 'col-resize',
-          '&:hover, &.Mui-resizing': {
+          touchAction: 'none',
+          '&:hover': {
+            color: theme.palette.text.primary,
+            // Reset on touch devices, it doesn't add specificity
+            '@media (hover: none)': {
+              color: borderColor,
+            },
+          },
+          '&.Mui-resizing': {
             color: theme.palette.text.primary,
           },
         },

packages/grid/_modules_/grid/constants/cssClassesConstants.ts

@@ -2,6 +2,7 @@
 export const CELL_CSS_CLASS = 'MuiDataGrid-cell';
 export const ROW_CSS_CLASS = 'MuiDataGrid-row';
 export const HEADER_CELL_CSS_CLASS = 'MuiDataGrid-colCell';
+export const HEADER_CELL_SEPARATOR_RESIZABLE_CSS_CLASS = 'MuiDataGrid-columnSeparatorResizable';
 export const DATA_CONTAINER_CSS_CLASS = 'data-container';
 export const HEADER_CELL_DROP_ZONE_CSS_CLASS = 'MuiDataGrid-colCell-dropZone';
 export const HEADER_CELL_DRAGGING_CSS_CLASS = 'MuiDataGrid-colCell-dragging';

packages/grid/_modules_/grid/hooks/features/useColumnResize.tsx

@@ -4,11 +4,54 @@ import { ColDef } from '../../models/colDef';
 import { useLogger } from '../utils';
 import { useEventCallback } from '../../utils/material-ui-utils';
 import { COL_RESIZE_START, COL_RESIZE_STOP } from '../../constants/eventsConstants';
-import { HEADER_CELL_CSS_CLASS } from '../../constants/cssClassesConstants';
-import { findCellElementsFromCol } from '../../utils';
+import {
+  HEADER_CELL_CSS_CLASS,
+  HEADER_CELL_SEPARATOR_RESIZABLE_CSS_CLASS,
+} from '../../constants/cssClassesConstants';
+import { findCellElementsFromCol, findParentElementFromClassName } from '../../utils/domUtils';
 import { ApiRef } from '../../models';
+import { CursorCoordinates } from '../../models/api/columnReorderApi';
 
 const MIN_COL_WIDTH = 50;
+let cachedSupportsTouchActionNone = false;
+
+// TODO: remove support for Safari < 13.
+// https://caniuse.com/#search=touch-action
+//
+// Safari, on iOS, supports touch action since v13.
+// Over 80% of the iOS phones are compatible
+// in August 2020.
+function doesSupportTouchActionNone(): boolean {
+  if (!cachedSupportsTouchActionNone) {
+    const element = document.createElement('div');
+    element.style.touchAction = 'none';
+    document.body.appendChild(element);
+    cachedSupportsTouchActionNone = window.getComputedStyle(element).touchAction === 'none';
+    element.parentElement!.removeChild(element);
+  }
+  return cachedSupportsTouchActionNone;
+}
+
+function trackFinger(event, currentTouchId): CursorCoordinates | boolean {
+  if (currentTouchId !== undefined && event.changedTouches) {
+    for (let i = 0; i < event.changedTouches.length; i += 1) {
+      const touch = event.changedTouches[i];
+      if (touch.identifier === currentTouchId) {
+        return {
+          x: touch.clientX,
+          y: touch.clientY,
+        };
+      }
+    }
+
+    return false;
+  }
+
+  return {
+    x: event.clientX,
+    y: event.clientY,
+  };
+}
 
 // TODO improve experience for last column
 export const useColumnResize = (columnsRef: React.RefObject<HTMLDivElement>, apiRef: ApiRef) => {
@@ -18,6 +61,8 @@ export const useColumnResize = (columnsRef: React.RefObject<HTMLDivElement>, api
   const colCellElementsRef = React.useRef<NodeListOf<Element>>();
   const initialOffset = React.useRef<number>();
   const stopResizeEventTimeout = React.useRef<number>();
+  const touchId = React.useRef<number>();
+  const columnsHeaderElement = columnsRef.current;
 
   const updateWidth = (newWidth: number) => {
     logger.debug(`Updating width to ${newWidth} for col ${colDefRef.current!.field}`);
@@ -81,8 +126,9 @@ export const useColumnResize = (columnsRef: React.RefObject<HTMLDivElement>, api
     // Avoid text selection
     event.preventDefault();
 
-    colElementRef.current = event.currentTarget.closest(
-      `.${HEADER_CELL_CSS_CLASS}`,
+    colElementRef.current = findParentElementFromClassName(
+      event.currentTarget,
+      HEADER_CELL_CSS_CLASS,
     ) as HTMLDivElement;
     const field = colElementRef.current.getAttribute('data-field') as string;
     const colDef = apiRef.current.getColumnFromField(field);
@@ -91,7 +137,7 @@ export const useColumnResize = (columnsRef: React.RefObject<HTMLDivElement>, api
     apiRef.current.publishEvent(COL_RESIZE_START, { field });
 
     colDefRef.current = colDef;
-    colElementRef.current = columnsRef.current!.querySelector(
+    colElementRef.current = columnsHeaderElement!.querySelector(
       `[data-field="${colDef.field}"]`,
     ) as HTMLDivElement;
 
@@ -110,19 +156,121 @@ export const useColumnResize = (columnsRef: React.RefObject<HTMLDivElement>, api
     doc.addEventListener('mouseup', handleResizeMouseUp);
   });
 
+  const handleTouchEnd = useEventCallback((nativeEvent) => {
+    const finger = trackFinger(nativeEvent, touchId.current);
+
+    if (!finger) {
+      return;
+    }
+
+    // eslint-disable-next-line @typescript-eslint/no-use-before-define
+    stopListening();
+
+    apiRef.current!.updateColumn(colDefRef.current as ColDef);
+
+    clearTimeout(stopResizeEventTimeout.current);
+    stopResizeEventTimeout.current = setTimeout(() => {
+      apiRef.current.publishEvent(COL_RESIZE_STOP);
+    });
+
+    logger.debug(
+      `Updating col ${colDefRef.current!.field} with new width: ${colDefRef.current!.width}`,
+    );
+  });
+
+  const handleTouchMove = useEventCallback((nativeEvent) => {
+    const finger = trackFinger(nativeEvent, touchId.current);
+    if (!finger) {
+      return;
+    }
+
+    // Cancel move in case some other element consumed a touchmove event and it was not fired.
+    if (nativeEvent.type === 'mousemove' && nativeEvent.buttons === 0) {
+      handleTouchEnd(nativeEvent);
+      return;
+    }
+
+    let newWidth =
+      initialOffset.current! +
+      (finger as CursorCoordinates).x -
+      colElementRef.current!.getBoundingClientRect().left;
+    newWidth = Math.max(MIN_COL_WIDTH, newWidth);
+
+    updateWidth(newWidth);
+  });
+
+  const handleTouchStart = useEventCallback((event) => {
+    const cellSeparator = findParentElementFromClassName(
+      event.target,
+      HEADER_CELL_SEPARATOR_RESIZABLE_CSS_CLASS,
+    );
+    // Let the event bubble if the target is not a col separator
+    if (!cellSeparator) return;
+    // If touch-action: none; is not supported we need to prevent the scroll manually.
+    if (!doesSupportTouchActionNone()) {
+      event.preventDefault();
+    }
+
+    const touch = event.changedTouches[0];
+    if (touch != null) {
+      // A number that uniquely identifies the current finger in the touch session.
+      touchId.current = touch.identifier;
+    }
+
+    colElementRef.current = findParentElementFromClassName(
+      event.target,
+      HEADER_CELL_CSS_CLASS,
+    ) as HTMLDivElement;
+    const field = colElementRef.current!.getAttribute('data-field') as string;
+    const colDef = apiRef.current.getColumnFromField(field);
+
+    logger.debug(`Start Resize on col ${colDef.field}`);
+    apiRef.current.publishEvent(COL_RESIZE_START, { field });
+
+    colDefRef.current = colDef;
+    colElementRef.current = columnsHeaderElement!.querySelector(
+      `[data-field="${colDef.field}"]`,
+    ) as HTMLDivElement;
+
+    colCellElementsRef.current = findCellElementsFromCol(colElementRef.current) as NodeListOf<
+      Element
+    >;
+
+    initialOffset.current =
+      (colDefRef.current.width as number) -
+      (touch.clientX - colElementRef.current!.getBoundingClientRect().left);
+
+    const doc = ownerDocument(event.currentTarget as HTMLElement);
+    doc.addEventListener('touchmove', handleTouchMove);
+    doc.addEventListener('touchend', handleTouchEnd);
+  });
+
   const stopListening = React.useCallback(() => {
     const doc = ownerDocument(apiRef.current.rootElementRef!.current as HTMLElement);
     doc.body.style.removeProperty('cursor');
     doc.removeEventListener('mousemove', handleResizeMouseMove);
     doc.removeEventListener('mouseup', handleResizeMouseUp);
-  }, [apiRef, handleResizeMouseMove, handleResizeMouseUp]);
+    doc.removeEventListener('touchmove', handleTouchMove);
+    doc.removeEventListener('touchend', handleTouchEnd);
+  }, [apiRef, handleResizeMouseMove, handleResizeMouseUp, handleTouchMove, handleTouchEnd]);
 
   React.useEffect(() => {
+    columnsHeaderElement?.addEventListener('touchstart', handleTouchStart, {
+      passive: doesSupportTouchActionNone(),
+    });
+
     return () => {
+      columnsHeaderElement?.removeEventListener('touchstart', handleTouchStart);
+
       clearTimeout(stopResizeEventTimeout.current);
       stopListening();
     };
-  }, [stopListening]);
+  }, [columnsHeaderElement, handleTouchStart, stopListening]);
 
-  return React.useMemo(() => ({ onMouseDown: handleMouseDown }), [handleMouseDown]);
+  return React.useMemo(
+    () => ({
+      onMouseDown: handleMouseDown,
+    }),
+    [handleMouseDown],
+  );
 };

packages/grid/_modules_/grid/hooks/features/virtualization/useVirtualRows.ts

@@ -37,7 +37,7 @@ export const useVirtualRows = (
   const paginationState = useGridSelector<PaginationState>(apiRef, paginationSelector);
   const totalRowCount = useGridSelector<number>(apiRef, rowCountSelector);
 
-  const [scrollTo] = useScrollFn(apiRef, renderingZoneRef, colRef);
+  const [scrollTo] = useScrollFn(renderingZoneRef, colRef);
   const [renderedColRef, updateRenderedCols] = useVirtualColumns(options, apiRef);
 
   const setRenderingState = React.useCallback(

packages/grid/_modules_/grid/hooks/utils/useScrollFn.ts

@@ -4,7 +4,6 @@ import { ScrollFn, ScrollParams } from '../../models/params/scrollParams';
 import { useLogger } from './useLogger';
 
 export function useScrollFn(
-  apiRef: any,
   renderingZoneElementRef: React.RefObject<HTMLDivElement>,
   columnHeadersElementRef: React.RefObject<HTMLDivElement>,
 ): [ScrollFn] {

packages/storybook/src/stories/grid-resize.stories.tsx

@@ -30,7 +30,7 @@ export const ResizeSmallDataset = () => {
           Switch sizes
         </button>
       </div>
-      <div style={{ width: size.width, height: size.height, display: 'flex' }}>
+      <div style={{ width: size.width, height: size.height }}>
         <XGrid rows={data.rows} columns={data.columns} />
       </div>
     </React.Fragment>