Notify to resize the timeline when the pinned message banner is displayed or hidden (#28654)

src/components/structures/RoomView.tsx

@@ -2372,7 +2372,11 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         );
 
         const pinnedMessageBanner = (
-            <PinnedMessageBanner room={this.state.room} permalinkCreator={this.permalinkCreator} />
+            <PinnedMessageBanner
+                room={this.state.room}
+                permalinkCreator={this.permalinkCreator}
+                resizeNotifier={this.props.resizeNotifier}
+            />
         );
 
         let messageComposer;

src/components/views/rooms/PinnedMessageBanner.tsx

@@ -6,10 +6,10 @@
  * Please see LICENSE files in the repository root for full details.
  */
 
-import React, { JSX, useEffect, useState } from "react";
+import React, { JSX, useEffect, useRef, useState } from "react";
 import PinIcon from "@vector-im/compound-design-tokens/assets/web/icons/pin-solid";
 import { Button } from "@vector-im/compound-web";
-import { Room } from "matrix-js-sdk/src/matrix";
+import { MatrixEvent, Room } from "matrix-js-sdk/src/matrix";
 import classNames from "classnames";
 
 import { usePinnedEvents, useSortedFetchedPinnedEvents } from "../../../hooks/usePinnedEvents";
@@ -25,6 +25,7 @@ import { Action } from "../../../dispatcher/actions";
 import MessageEvent from "../messages/MessageEvent";
 import PosthogTrackers from "../../../PosthogTrackers.ts";
 import { EventPreview } from "./EventPreview.tsx";
+import ResizeNotifier from "../../../utils/ResizeNotifier";
 
 /**
  * The props for the {@link PinnedMessageBanner} component.
@@ -38,12 +39,20 @@ interface PinnedMessageBannerProps {
      * The room where the banner is displayed
      */
     room: Room;
+    /**
+     * The resize notifier to notify the timeline to resize itself when the banner is displayed or hidden.
+     */
+    resizeNotifier: ResizeNotifier;
 }
 
 /**
  * A banner that displays the pinned messages in a room.
  */
-export function PinnedMessageBanner({ room, permalinkCreator }: PinnedMessageBannerProps): JSX.Element | null {
+export function PinnedMessageBanner({
+    room,
+    permalinkCreator,
+    resizeNotifier,
+}: PinnedMessageBannerProps): JSX.Element | null {
     const pinnedEventIds = usePinnedEvents(room);
     const pinnedEvents = useSortedFetchedPinnedEvents(room, pinnedEventIds);
     const eventCount = pinnedEvents.length;
@@ -56,6 +65,8 @@ export function PinnedMessageBanner({ room, permalinkCreator }: PinnedMessageBan
     }, [eventCount]);
 
     const pinnedEvent = pinnedEvents[currentEventIndex];
+    useNotifyTimeline(pinnedEvent, resizeNotifier);
+
     if (!pinnedEvent) return null;
 
     const shouldUseMessageEvent = pinnedEvent.isRedacted() || pinnedEvent.isDecryptionFailure();
@@ -128,6 +139,23 @@ export function PinnedMessageBanner({ room, permalinkCreator }: PinnedMessageBan
     );
 }
 
+/**
+ * When the banner is displayed or hidden, we want to notify the timeline to resize itself.
+ * @param pinnedEvent
+ * @param resizeNotifier
+ */
+function useNotifyTimeline(pinnedEvent: MatrixEvent | null, resizeNotifier: ResizeNotifier): void {
+    const previousEvent = useRef<MatrixEvent | null>(null);
+    useEffect(() => {
+        // If we switch from a pinned message to no pinned message or the opposite, we want to resize the timeline
+        if ((previousEvent.current && !pinnedEvent) || (!previousEvent.current && pinnedEvent)) {
+            resizeNotifier.notifyTimelineHeightChanged();
+        }
+
+        previousEvent.current = pinnedEvent;
+    }, [pinnedEvent, resizeNotifier]);
+}
+
 const MAX_INDICATORS = 3;
 
 /**

test/unit-tests/components/views/rooms/PinnedMessageBanner-test.tsx

@@ -20,6 +20,7 @@ import RightPanelStore from "../../../../../src/stores/right-panel/RightPanelSto
 import { RightPanelPhases } from "../../../../../src/stores/right-panel/RightPanelStorePhases";
 import { UPDATE_EVENT } from "../../../../../src/stores/AsyncStore";
 import { Action } from "../../../../../src/dispatcher/actions";
+import ResizeNotifier from "../../../../../src/utils/ResizeNotifier.ts";
 
 describe("<PinnedMessageBanner />", () => {
     const userId = "@alice:server.org";
@@ -28,10 +29,12 @@ describe("<PinnedMessageBanner />", () => {
     let mockClient: MatrixClient;
     let room: Room;
     let permalinkCreator: RoomPermalinkCreator;
+    let resizeNotifier: ResizeNotifier;
     beforeEach(() => {
         mockClient = stubClient();
         room = new Room(roomId, mockClient, userId);
         permalinkCreator = new RoomPermalinkCreator(room);
+        resizeNotifier = new ResizeNotifier();
         jest.spyOn(dis, "dispatch").mockReturnValue(undefined);
     });
 
@@ -77,7 +80,7 @@ describe("<PinnedMessageBanner />", () => {
      */
     function renderBanner() {
         return render(
-            <PinnedMessageBanner permalinkCreator={permalinkCreator} room={room} />,
+            <PinnedMessageBanner permalinkCreator={permalinkCreator} room={room} resizeNotifier={resizeNotifier} />,
             withClientContextRenderOptions(mockClient),
         );
     }
@@ -145,7 +148,9 @@ describe("<PinnedMessageBanner />", () => {
             event3.getId()!,
         ]);
         jest.spyOn(pinnedEventHooks, "useSortedFetchedPinnedEvents").mockReturnValue([event1, event2, event3]);
-        rerender(<PinnedMessageBanner permalinkCreator={permalinkCreator} room={room} />);
+        rerender(
+            <PinnedMessageBanner permalinkCreator={permalinkCreator} room={room} resizeNotifier={resizeNotifier} />,
+        );
         await expect(screen.findByText("Third pinned message")).resolves.toBeVisible();
         expect(asFragment()).toMatchSnapshot();
     });
@@ -206,6 +211,42 @@ describe("<PinnedMessageBanner />", () => {
         expect(asFragment()).toMatchSnapshot();
     });
 
+    describe("Notify the timeline to resize", () => {
+        beforeEach(() => {
+            jest.spyOn(resizeNotifier, "notifyTimelineHeightChanged");
+            jest.spyOn(pinnedEventHooks, "usePinnedEvents").mockReturnValue([event1.getId()!, event2.getId()!]);
+            jest.spyOn(pinnedEventHooks, "useSortedFetchedPinnedEvents").mockReturnValue([event1, event2]);
+        });
+
+        it("should notify the timeline to resize when we display the banner", async () => {
+            renderBanner();
+            await expect(screen.findByText("Second pinned message")).resolves.toBeVisible();
+            // The banner is displayed, so we need to resize the timeline
+            expect(resizeNotifier.notifyTimelineHeightChanged).toHaveBeenCalledTimes(1);
+
+            await userEvent.click(screen.getByRole("button", { name: "View the pinned message in the timeline." }));
+            await expect(screen.findByText("First pinned message")).resolves.toBeVisible();
+            // The banner is already displayed, so we don't need to resize the timeline
+            expect(resizeNotifier.notifyTimelineHeightChanged).toHaveBeenCalledTimes(1);
+        });
+
+        it("should notify the timeline to resize when we hide the banner", async () => {
+            const { rerender } = renderBanner();
+            await expect(screen.findByText("Second pinned message")).resolves.toBeVisible();
+            // The banner is displayed, so we need to resize the timeline
+            expect(resizeNotifier.notifyTimelineHeightChanged).toHaveBeenCalledTimes(1);
+
+            // The banner has no event to display and is hidden
+            jest.spyOn(pinnedEventHooks, "usePinnedEvents").mockReturnValue([]);
+            jest.spyOn(pinnedEventHooks, "useSortedFetchedPinnedEvents").mockReturnValue([]);
+            rerender(
+                <PinnedMessageBanner permalinkCreator={permalinkCreator} room={room} resizeNotifier={resizeNotifier} />,
+            );
+            // The timeline should be resized
+            expect(resizeNotifier.notifyTimelineHeightChanged).toHaveBeenCalledTimes(2);
+        });
+    });
+
     describe("Right button", () => {
         beforeEach(() => {
             jest.spyOn(pinnedEventHooks, "usePinnedEvents").mockReturnValue([event1.getId()!, event2.getId()!]);
@@ -217,6 +258,8 @@ describe("<PinnedMessageBanner />", () => {
             jest.spyOn(RightPanelStore.instance, "isOpenForRoom").mockReturnValue(false);
 
             renderBanner();
+            await expect(screen.findByText("Second pinned message")).resolves.toBeVisible();
+
             expect(screen.getByRole("button", { name: "View all" })).toBeVisible();
         });
 
@@ -228,6 +271,8 @@ describe("<PinnedMessageBanner />", () => {
             });
 
             renderBanner();
+            await expect(screen.findByText("Second pinned message")).resolves.toBeVisible();
+
             expect(screen.getByRole("button", { name: "View all" })).toBeVisible();
         });
 
@@ -239,6 +284,8 @@ describe("<PinnedMessageBanner />", () => {
             });
 
             renderBanner();
+            await expect(screen.findByText("Second pinned message")).resolves.toBeVisible();
+
             expect(screen.getByRole("button", { name: "Close list" })).toBeVisible();
         });
 
@@ -263,6 +310,7 @@ describe("<PinnedMessageBanner />", () => {
             });
 
             renderBanner();
+            await expect(screen.findByText("Second pinned message")).resolves.toBeVisible();
             expect(screen.getByRole("button", { name: "Close list" })).toBeVisible();
 
             jest.spyOn(RightPanelStore.instance, "isOpenForRoom").mockReturnValue(false);