[docs] Add collapsible column groups demo

docs/data/data-grid/column-groups/CollapsibleColumnGroups.js

@@ -0,0 +1,123 @@
+import * as React from 'react';
+import { styled } from '@mui/material/styles';
+import Box from '@mui/material/Box';
+import IconButton from '@mui/material/IconButton';
+import {
+  DataGrid,
+  gridColumnVisibilityModelSelector,
+  useGridApiContext,
+} from '@mui/x-data-grid';
+import KeyboardArrowRightIcon from '@mui/icons-material/KeyboardArrowRight';
+import KeyboardArrowDownIcon from '@mui/icons-material/KeyboardArrowDown';
+
+const COLLAPSIBLE_COLUMN_GROUPS = {
+  character: ['lastName', 'age'],
+  naming: ['lastName'],
+};
+
+const ColumnGroupRoot = styled('div')({
+  overflow: 'hidden',
+  display: 'flex',
+  alignItems: 'center',
+});
+
+const ColumnGroupTitle = styled('span')({
+  overflow: 'hidden',
+  textOverflow: 'ellipsis',
+});
+
+function CollapsibleHeaderGroup({ groupId, headerName }) {
+  const apiRef = useGridApiContext();
+  const columnVisibilityModel = gridColumnVisibilityModelSelector(apiRef);
+
+  if (!groupId) {
+    return null;
+  }
+
+  const isCollapsible = Boolean(COLLAPSIBLE_COLUMN_GROUPS[groupId]);
+  const isGroupCollapsed = COLLAPSIBLE_COLUMN_GROUPS[groupId].every(
+    (field) => columnVisibilityModel[field] === false,
+  );
+
+  return (
+    <ColumnGroupRoot>
+      <ColumnGroupTitle>{headerName ?? groupId}</ColumnGroupTitle>{' '}
+      {isCollapsible && (
+        <IconButton
+          sx={{ ml: 0.5 }}
+          onClick={() => {
+            const newModel = { ...columnVisibilityModel };
+            COLLAPSIBLE_COLUMN_GROUPS[groupId].forEach((field) => {
+              newModel[field] = !!isGroupCollapsed;
+            });
+            apiRef.current.setColumnVisibilityModel(newModel);
+          }}
+        >
+          {isGroupCollapsed ? (
+            <KeyboardArrowRightIcon fontSize="small" />
+          ) : (
+            <KeyboardArrowDownIcon fontSize="small" />
+          )}
+        </IconButton>
+      )}
+    </ColumnGroupRoot>
+  );
+}
+
+const columnGroupingModel = [
+  {
+    groupId: 'Internal',
+    description: '',
+    children: [{ field: 'id' }],
+  },
+  {
+    groupId: 'character',
+    description: 'Information about the character',
+    headerName: 'Basic info',
+    renderHeaderGroup: (params) => {
+      return <CollapsibleHeaderGroup {...params} />;
+    },
+    children: [
+      {
+        groupId: 'naming',
+        headerName: 'Names',
+        renderHeaderGroup: (params) => <CollapsibleHeaderGroup {...params} />,
+        children: [{ field: 'lastName' }, { field: 'firstName' }],
+      },
+      { field: 'age' },
+    ],
+  },
+];
+
+const columns = [
+  { field: 'id', headerName: 'ID', width: 150 },
+  { field: 'firstName', headerName: 'First name', width: 150 },
+  { field: 'lastName', headerName: 'Last name', width: 150 },
+  { field: 'age', headerName: 'Age', type: 'number', width: 110 },
+];
+
+const rows = [
+  { id: 1, lastName: 'Snow', firstName: 'Jon', age: 35 },
+  { id: 2, lastName: 'Lannister', firstName: 'Cersei', age: 42 },
+  { id: 3, lastName: 'Lannister', firstName: 'Jaime', age: 45 },
+  { id: 4, lastName: 'Stark', firstName: 'Arya', age: 16 },
+  { id: 5, lastName: 'Targaryen', firstName: 'Daenerys', age: null },
+  { id: 6, lastName: 'Melisandre', firstName: null, age: 150 },
+  { id: 7, lastName: 'Clifford', firstName: 'Ferrara', age: 44 },
+  { id: 8, lastName: 'Frances', firstName: 'Rossini', age: 36 },
+  { id: 9, lastName: 'Roxie', firstName: 'Harvey', age: 65 },
+];
+
+export default function CollapsibleColumnGroups() {
+  return (
+    <Box sx={{ height: 400, width: '100%' }}>
+      <DataGrid
+        rows={rows}
+        columns={columns}
+        checkboxSelection
+        disableRowSelectionOnClick
+        columnGroupingModel={columnGroupingModel}
+      />
+    </Box>
+  );
+}

docs/data/data-grid/column-groups/CollapsibleColumnGroups.tsx

@@ -0,0 +1,129 @@
+import * as React from 'react';
+import { styled } from '@mui/material/styles';
+import Box from '@mui/material/Box';
+import IconButton from '@mui/material/IconButton';
+import {
+  DataGrid,
+  GridColDef,
+  GridColumnGroupHeaderParams,
+  GridColumnGroupingModel,
+  gridColumnVisibilityModelSelector,
+  useGridApiContext,
+} from '@mui/x-data-grid';
+import KeyboardArrowRightIcon from '@mui/icons-material/KeyboardArrowRight';
+import KeyboardArrowDownIcon from '@mui/icons-material/KeyboardArrowDown';
+
+const COLLAPSIBLE_COLUMN_GROUPS: Record<string, Array<string>> = {
+  character: ['lastName', 'age'],
+  naming: ['lastName'],
+};
+
+const ColumnGroupRoot = styled('div')({
+  overflow: 'hidden',
+  display: 'flex',
+  alignItems: 'center',
+});
+
+const ColumnGroupTitle = styled('span')({
+  overflow: 'hidden',
+  textOverflow: 'ellipsis',
+});
+
+function CollapsibleHeaderGroup({
+  groupId,
+  headerName,
+}: GridColumnGroupHeaderParams) {
+  const apiRef = useGridApiContext();
+  const columnVisibilityModel = gridColumnVisibilityModelSelector(apiRef);
+
+  if (!groupId) {
+    return null;
+  }
+
+  const isCollapsible = Boolean(COLLAPSIBLE_COLUMN_GROUPS[groupId]);
+  const isGroupCollapsed = COLLAPSIBLE_COLUMN_GROUPS[groupId].every(
+    (field) => columnVisibilityModel[field] === false,
+  );
+
+  return (
+    <ColumnGroupRoot>
+      <ColumnGroupTitle>{headerName ?? groupId}</ColumnGroupTitle>{' '}
+      {isCollapsible && (
+        <IconButton
+          sx={{ ml: 0.5 }}
+          onClick={() => {
+            const newModel = { ...columnVisibilityModel };
+            COLLAPSIBLE_COLUMN_GROUPS[groupId].forEach((field) => {
+              newModel[field] = !!isGroupCollapsed;
+            });
+            apiRef.current.setColumnVisibilityModel(newModel);
+          }}
+        >
+          {isGroupCollapsed ? (
+            <KeyboardArrowRightIcon fontSize="small" />
+          ) : (
+            <KeyboardArrowDownIcon fontSize="small" />
+          )}
+        </IconButton>
+      )}
+    </ColumnGroupRoot>
+  );
+}
+
+const columnGroupingModel: GridColumnGroupingModel = [
+  {
+    groupId: 'Internal',
+    description: '',
+    children: [{ field: 'id' }],
+  },
+  {
+    groupId: 'character',
+    description: 'Information about the character',
+    headerName: 'Basic info',
+    renderHeaderGroup: (params) => {
+      return <CollapsibleHeaderGroup {...params} />;
+    },
+    children: [
+      {
+        groupId: 'naming',
+        headerName: 'Names',
+        renderHeaderGroup: (params) => <CollapsibleHeaderGroup {...params} />,
+        children: [{ field: 'lastName' }, { field: 'firstName' }],
+      },
+      { field: 'age' },
+    ],
+  },
+];
+
+const columns: GridColDef[] = [
+  { field: 'id', headerName: 'ID', width: 150 },
+  { field: 'firstName', headerName: 'First name', width: 150 },
+  { field: 'lastName', headerName: 'Last name', width: 150 },
+  { field: 'age', headerName: 'Age', type: 'number', width: 110 },
+];
+
+const rows = [
+  { id: 1, lastName: 'Snow', firstName: 'Jon', age: 35 },
+  { id: 2, lastName: 'Lannister', firstName: 'Cersei', age: 42 },
+  { id: 3, lastName: 'Lannister', firstName: 'Jaime', age: 45 },
+  { id: 4, lastName: 'Stark', firstName: 'Arya', age: 16 },
+  { id: 5, lastName: 'Targaryen', firstName: 'Daenerys', age: null },
+  { id: 6, lastName: 'Melisandre', firstName: null, age: 150 },
+  { id: 7, lastName: 'Clifford', firstName: 'Ferrara', age: 44 },
+  { id: 8, lastName: 'Frances', firstName: 'Rossini', age: 36 },
+  { id: 9, lastName: 'Roxie', firstName: 'Harvey', age: 65 },
+];
+
+export default function CollapsibleColumnGroups() {
+  return (
+    <Box sx={{ height: 400, width: '100%' }}>
+      <DataGrid
+        rows={rows}
+        columns={columns}
+        checkboxSelection
+        disableRowSelectionOnClick
+        columnGroupingModel={columnGroupingModel}
+      />
+    </Box>
+  );
+}

docs/data/data-grid/column-groups/CollapsibleColumnGroups.tsx.preview

@@ -0,0 +1,7 @@
+<DataGrid
+  rows={rows}
+  columns={columns}
+  checkboxSelection
+  disableRowSelectionOnClick
+  columnGroupingModel={columnGroupingModel}
+/>

docs/data/data-grid/column-groups/column-groups.md

@@ -74,6 +74,12 @@ In the example below, the `Full name` column group can be divided, but not other
 
 {{"demo": "BreakingGroupDemo.js", "disableAd": true, "bg": "inline"}}
 
+## Collapsible column groups
+
+The demo below uses [`renderHeaderGroup`](/x/react-data-grid/column-groups/#customize-column-group) to add a button to collapse/expand the column group.
+
+{{"demo": "CollapsibleColumnGroups.js", "bg": "inline"}}
+
 ## Manage group visibility 🚧
 
 The column group should allow to switch between an extended/collapsed view which hide/show some columns.