RoomBreadcrumbs2 -> RoomBreadcrumbs

src/components/views/rooms/RoomBreadcrumbs.tsx

@@ -0,0 +1,129 @@
+/*
+Copyright 2020 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import React from "react";
+import { BreadcrumbsStore } from "../../../stores/BreadcrumbsStore";
+import DecoratedRoomAvatar from "../avatars/DecoratedRoomAvatar";
+import { _t } from "../../../languageHandler";
+import { Room } from "matrix-js-sdk/src/models/room";
+import defaultDispatcher from "../../../dispatcher/dispatcher";
+import Analytics from "../../../Analytics";
+import { UPDATE_EVENT } from "../../../stores/AsyncStore";
+import { CSSTransition } from "react-transition-group";
+import RoomListStore from "../../../stores/room-list/RoomListStore";
+import { DefaultTagID } from "../../../stores/room-list/models";
+import { RovingAccessibleTooltipButton } from "../../../accessibility/RovingTabIndex";
+import Toolbar from "../../../accessibility/Toolbar";
+
+interface IProps {
+}
+
+interface IState {
+    // Both of these control the animation for the breadcrumbs. For details on the
+    // actual animation, see the CSS.
+    //
+    // doAnimation is to lie to the CSSTransition component (see onBreadcrumbsUpdate
+    // for info). skipFirst is used to try and reduce jerky animation - also see the
+    // breadcrumb update function for info on that.
+    doAnimation: boolean;
+    skipFirst: boolean;
+}
+
+export default class RoomBreadcrumbs extends React.PureComponent<IProps, IState> {
+    private isMounted = true;
+
+    constructor(props: IProps) {
+        super(props);
+
+        this.state = {
+            doAnimation: true, // technically we want animation on mount, but it won't be perfect
+            skipFirst: false, // render the thing, as boring as it is
+        };
+
+        BreadcrumbsStore.instance.on(UPDATE_EVENT, this.onBreadcrumbsUpdate);
+    }
+
+    public componentWillUnmount() {
+        this.isMounted = false;
+        BreadcrumbsStore.instance.off(UPDATE_EVENT, this.onBreadcrumbsUpdate);
+    }
+
+    private onBreadcrumbsUpdate = () => {
+        if (!this.isMounted) return;
+
+        // We need to trick the CSSTransition component into updating, which means we need to
+        // tell it to not animate, then to animate a moment later. This causes two updates
+        // which means two renders. The skipFirst change is so that our don't-animate state
+        // doesn't show the breadcrumb we're about to reveal as it causes a visual jump/jerk.
+        // The second update, on the next available tick, causes the "enter" animation to start
+        // again and this time we want to show the newest breadcrumb because it'll be hidden
+        // off screen for the animation.
+        this.setState({doAnimation: false, skipFirst: true});
+        setTimeout(() => this.setState({doAnimation: true, skipFirst: false}), 0);
+    };
+
+    private viewRoom = (room: Room, index: number) => {
+        Analytics.trackEvent("Breadcrumbs", "click_node", index);
+        defaultDispatcher.dispatch({action: "view_room", room_id: room.roomId});
+    };
+
+    public render(): React.ReactElement {
+        const tiles = BreadcrumbsStore.instance.rooms.map((r, i) => {
+            const roomTags = RoomListStore.instance.getTagsForRoom(r);
+            const roomTag = roomTags.includes(DefaultTagID.DM) ? DefaultTagID.DM : roomTags[0];
+            return (
+                <RovingAccessibleTooltipButton
+                    className="mx_RoomBreadcrumbs_crumb"
+                    key={r.roomId}
+                    onClick={() => this.viewRoom(r, i)}
+                    aria-label={_t("Room %(name)s", {name: r.name})}
+                    title={r.name}
+                    tooltipClassName="mx_RoomBreadcrumbs_Tooltip"
+                >
+                    <DecoratedRoomAvatar
+                        room={r}
+                        avatarSize={32}
+                        tag={roomTag}
+                        displayBadge={true}
+                        forceCount={true}
+                    />
+                </RovingAccessibleTooltipButton>
+            );
+        });
+
+        if (tiles.length > 0) {
+            // NOTE: The CSSTransition timeout MUST match the timeout in our CSS!
+            return (
+                <CSSTransition
+                    appear={true} in={this.state.doAnimation} timeout={640}
+                    classNames='mx_RoomBreadcrumbs'
+                >
+                    <Toolbar className='mx_RoomBreadcrumbs'>
+                        {tiles.slice(this.state.skipFirst ? 1 : 0)}
+                    </Toolbar>
+                </CSSTransition>
+            );
+        } else {
+            return (
+                <div className='mx_RoomBreadcrumbs'>
+                    <div className="mx_RoomBreadcrumbs_placeholder">
+                        {_t("No recently visited rooms")}
+                    </div>
+                </div>
+            );
+        }
+    }
+}