Fix DropdownMenu component issues

.changeset/hot-swans-help.md

@@ -0,0 +1,7 @@
+---
+'@commercetools-uikit/dropdown-menu': minor
+---
+
+We've fixed two issues we had regarding floating menu position when scrolling and its height.
+
+We're also introducing a new property (`menuMaxHeight`) which allows consumers to limit the floating panel maximum height.

packages/components/dropdowns/dropdown-menu/README.md

@@ -90,6 +90,7 @@ export const CustomDropdownExample = () => {
 | Props                      | Type                                                  | Required | Default     | Description                                                                                                                                                             |
 | -------------------------- | ----------------------------------------------------- | :------: | ----------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `menuPosition`             | `union`<br/>Possible values:<br/>`'left' , 'right'`   |          | `'left'`    | The position of the menu relative to the trigger element.                                                                                                               |
+| `menuMaxHeight`            | `number`                                              |          |             | The maximum height for the menu in pixels.&#xA;By default, the max height will be the available space between the trigger element and the bottom of the viewport.       |
 | `triggerElement`           | `ReactElement`                                        |    ✅    |             | The element that triggers the dropdown.                                                                                                                                 |
 | `menuType`                 | `union`<br/>Possible values:<br/>`'default' , 'list'` |          | `'default'` | The type of the menu.&#xA;The 'default' type just renders a dropdown container but the 'list' type is intended to be used with the DropdownMenu.ListMenuItem component. |
 | `menuHorizontalConstraint` | `TMaxProp`                                            |          | `'auto'`    | The horizontal constraint of the menu.                                                                                                                                  |

packages/components/dropdowns/dropdown-menu/src/dropdown-menu.story.js

@@ -1,6 +1,6 @@
 import { Value } from 'react-value';
 import { storiesOf } from '@storybook/react';
-import { withKnobs, select } from '@storybook/addon-knobs/react';
+import { withKnobs, select, number } from '@storybook/addon-knobs/react';
 import { action } from '@storybook/addon-actions';
 import CheckboxInput from '@commercetools-uikit/checkbox-input';
 import Constraints from '@commercetools-uikit/constraints';
@@ -24,30 +24,31 @@ storiesOf('Components|Dropdowns|DropdownMenu', module)
       sidebar: Readme,
     },
   })
-  .add('DropdownMenu - List menu content', () => (
-    <Section align="center">
-      <DropdownMenu
-        triggerElement={<IconButton icon={<ColumnsIcon />} label="list" />}
-        menuHorizontalConstraint={select(
-          'menu horizontalConstraint',
-          Constraints.getAcceptedMaxPropValues(),
-          6
-        )}
-        menuPosition={select('Menu position', ['left', 'right'], 'left')}
-        menuType="list"
-      >
-        <DropdownMenu.ListMenuItem onClick={action('onClick')}>
-          Option 1
-        </DropdownMenu.ListMenuItem>
-        <DropdownMenu.ListMenuItem onClick={action('onClick')} isDisabled>
-          Option 2
-        </DropdownMenu.ListMenuItem>
-        <DropdownMenu.ListMenuItem onClick={action('onClick')}>
-          Option 3
-        </DropdownMenu.ListMenuItem>
-      </DropdownMenu>
-    </Section>
-  ))
+  .add('DropdownMenu - List menu content', () => {
+    const optionsCount = number('Options count', 5);
+    return (
+      <Section align="center">
+        <DropdownMenu
+          triggerElement={<IconButton icon={<ColumnsIcon />} label="list" />}
+          menuHorizontalConstraint={select(
+            'menu horizontalConstraint',
+            Constraints.getAcceptedMaxPropValues(),
+            6
+          )}
+          menuPosition={select('Menu position', ['left', 'right'], 'left')}
+          menuMaxHeight={number('menuMaxHeight', 0)}
+          menuType="list"
+        >
+          {new Array(optionsCount).fill().map((_, index) => (
+            <DropdownMenu.ListMenuItem
+              key={index}
+              onClick={action('onClick')}
+            >{`Option ${index + 1}`}</DropdownMenu.ListMenuItem>
+          ))}
+        </DropdownMenu>
+      </Section>
+    );
+  })
   .add('DropdownMenu - Complex menu content', () => (
     <Section align="center">
       <DropdownMenu

packages/components/dropdowns/dropdown-menu/src/dropdown-menu.tsx

@@ -1,9 +1,11 @@
-import React, {
+import {
   useCallback,
   useEffect,
   useMemo,
+  useRef,
   type ReactElement,
   type ReactNode,
+  type RefObject,
 } from 'react';
 import { useToggleState } from '@commercetools-uikit/hooks';
 import { type TMaxProp } from '@commercetools-uikit/constraints';
@@ -21,6 +23,11 @@ export type TDropdownMenuProps = {
    * The position of the menu relative to the trigger element.
    */
   menuPosition?: 'left' | 'right';
+  /**
+   * The maximum height for the menu in pixels.
+   * By default, the max height will be the available space between the trigger element and the bottom of the viewport.
+   */
+  menuMaxHeight?: number;
   /**
    * The element that triggers the dropdown.
    */
@@ -40,6 +47,48 @@ export type TDropdownMenuProps = {
   children: ReactNode;
 };
 
+function getScrollableParent(element: HTMLElement | null): HTMLElement | null {
+  if (!element) {
+    return null;
+  }
+  const overflowY = window.getComputedStyle(element).overflowY;
+  const isScrollable = overflowY !== 'visible' && overflowY !== 'hidden';
+  if (isScrollable && element.scrollHeight >= element.clientHeight) {
+    return element;
+  }
+
+  return getScrollableParent(element.parentElement);
+}
+
+function useScrollBlock(isOpen: boolean, triggerRef: RefObject<HTMLElement>) {
+  const scrollableParentRef = useRef<HTMLElement | null>();
+
+  useEffect(() => {
+    if (!scrollableParentRef.current) {
+      scrollableParentRef.current = getScrollableParent(triggerRef.current);
+    }
+
+    const { current: scrollableParent } = scrollableParentRef;
+    if (scrollableParent && isOpen) {
+      scrollableParent.setAttribute(
+        'data-prev-scroll',
+        scrollableParent.style.overflowY
+      );
+      scrollableParent.style.overflowY = 'hidden';
+    }
+    return () => {
+      // The cleanup effect runs after the component is unmounted but also everytime
+      // the dependency array changes. We need to manage both to manage opening/closing
+      // the dropdown but also to manage the the dropdown is opened and the component
+      // is unmounted. For instance, when navigating to another page client-side.
+      if (scrollableParent && isOpen) {
+        const prevScroll = scrollableParent.getAttribute('data-prev-scroll');
+        scrollableParent.style.overflowY = prevScroll || '';
+      }
+    };
+  }, [isOpen, scrollableParentRef, triggerRef]);
+}
+
 const defaultProps: Pick<
   TDropdownMenuProps,
   'menuPosition' | 'menuType' | 'menuHorizontalConstraint'
@@ -56,7 +105,7 @@ const Container = styled.div`
 
 function DropdownMenu(props: TDropdownMenuProps) {
   const [isOpen, toggle] = useToggleState(false);
-  const triggerRef = React.useRef<HTMLDivElement>(null);
+  const triggerRef = useRef<HTMLDivElement>(null);
 
   // We use the context so children can toggle the dropdown
   const context = useMemo(
@@ -91,17 +140,10 @@ function DropdownMenu(props: TDropdownMenuProps) {
       window.removeEventListener('click', handleGlobalClick);
     };
   }, [handleGlobalClick]);
-  // Block scrolling when the dropdown is open
-  useEffect(() => {
-    if (isOpen) {
-      window.document.body.style.overflow = 'hidden';
-    } else {
-      window.document.body.style.overflow = 'initial';
-    }
-    return () => {
-      window.document.body.style.overflow = 'initial';
-    };
-  }, [isOpen]);
+
+  // Block scrolling when the dropdown is open.
+  // We do this to avoid requiring dropdown rerendering while the user scrolls.
+  useScrollBlock(isOpen, triggerRef);
 
   return (
     <DropdownMenuContext.Provider value={context}>
@@ -114,6 +156,7 @@ function DropdownMenu(props: TDropdownMenuProps) {
           horizontalConstraint={props.menuHorizontalConstraint!}
           isOpen={isOpen}
           menuPosition={props.menuPosition!}
+          menuMaxHeight={props.menuMaxHeight}
           triggerElementRef={triggerRef}
         >
           {props.children}

packages/components/dropdowns/dropdown-menu/src/menu/dropdown-menu-menu.tsx

@@ -10,6 +10,12 @@ import { designTokens } from '@commercetools-uikit/design-system';
 import Constraints, { type TMaxProp } from '@commercetools-uikit/constraints';
 import SpacingsStack from '@commercetools-uikit/spacings-stack';
 
+// We declare this style properties here because we need them both for initial component styling
+// but also for calculating the default max height of the dropdown menu so we make sure it fits
+// within the viewport.
+const boxShadowBottomSize = '5px';
+const marginTop = designTokens.spacing20;
+
 export function getDropdownMenuBaseStyles(params: {
   isOpen: boolean;
   horizontalConstraint: TMaxProp;
@@ -18,10 +24,11 @@ export function getDropdownMenuBaseStyles(params: {
     background-color: ${designTokens.colorSurface};
     border: 1px solid ${designTokens.colorSurface};
     border-radius: ${designTokens.borderRadius4};
-    box-shadow: 0 2px 5px 0px rgba(0, 0, 0, 0.15);
+    box-shadow: 0 2px ${boxShadowBottomSize} 0px rgba(0, 0, 0, 0.15);
     display: ${params.isOpen ? 'block' : 'none'};
-    margin-top: ${designTokens.spacing20};
+    margin-top: ${marginTop};
     max-width: ${Constraints.getMaxPropTokenValue(params.horizontalConstraint)};
+    overflow-y: auto;
     position: fixed;
     width: ${params.horizontalConstraint === 'auto' ? 'auto' : '100%'};
     z-index: 5;
@@ -34,6 +41,7 @@ type TDropdownBaseMenuProps = {
   horizontalConstraint: TMaxProp;
   isOpen: boolean;
   menuPosition: 'left' | 'right';
+  menuMaxHeight?: number;
   triggerElementRef: RefObject<HTMLElement>;
 };
 function DropdownBaseMenu(props: TDropdownBaseMenuProps) {
@@ -57,8 +65,19 @@ function DropdownBaseMenu(props: TDropdownBaseMenuProps) {
               triggerElementCoordinates.width -
               menuElementCoordinates.width
             }px`;
+      menuRef.current.style.maxHeight = props.menuMaxHeight
+        ? `${props.menuMaxHeight}px`
+        : `calc(${
+            window.innerHeight -
+            (triggerElementCoordinates.top + triggerElementCoordinates.height)
+          }px - ${marginTop} - ${boxShadowBottomSize})`;
     }
-  }, [props.isOpen, props.menuPosition, props.triggerElementRef]);
+  }, [
+    props.isOpen,
+    props.menuPosition,
+    props.triggerElementRef,
+    props.menuMaxHeight,
+  ]);
 
   return (
     <div
@@ -75,6 +94,7 @@ export type TDropdownContentMenuProps = {
   children: ReactNode;
   horizontalConstraint: TMaxProp;
   menuPosition: 'left' | 'right';
+  menuMaxHeight?: number;
   isOpen: boolean;
   triggerElementRef: RefObject<HTMLElement>;
 };
@@ -87,6 +107,7 @@ export const DropdownContentMenu = (props: TDropdownContentMenuProps) => {
       horizontalConstraint={props.horizontalConstraint}
       isOpen={props.isOpen}
       menuPosition={props.menuPosition}
+      menuMaxHeight={props.menuMaxHeight}
       triggerElementRef={props.triggerElementRef}
     >
       {props.children}
@@ -98,6 +119,7 @@ export type TDropdownListMenuProps = {
   children: ReactNode;
   horizontalConstraint: TMaxProp;
   menuPosition: 'left' | 'right';
+  menuMaxHeight?: number;
   isOpen: boolean;
   triggerElementRef: RefObject<HTMLElement>;
 };
@@ -107,6 +129,7 @@ export const DropdownListMenu = (props: TDropdownListMenuProps) => {
       horizontalConstraint={props.horizontalConstraint}
       isOpen={props.isOpen}
       menuPosition={props.menuPosition}
+      menuMaxHeight={props.menuMaxHeight}
       triggerElementRef={props.triggerElementRef}
     >
       <SpacingsStack scale="xs">{props.children}</SpacingsStack>