allow to inject custom tile view creator fn into timeline view

src/lib.ts

@@ -27,6 +27,8 @@ export {RoomViewModel} from "./domain/session/room/RoomViewModel.js";
 export {RoomView} from "./platform/web/ui/session/room/RoomView.js";
 export {TimelineViewModel} from "./domain/session/room/timeline/TimelineViewModel.js";
 export {TimelineView} from "./platform/web/ui/session/room/TimelineView";
+export {viewClassForEntry} from "./platform/web/ui/session/room/common";
+export type {TileViewConstructor, ViewClassForEntryFn} from "./platform/web/ui/session/room/TimelineView";
 export {Navigation} from "./domain/navigation/Navigation.js";
 export {ComposerViewModel} from "./domain/session/room/ComposerViewModel.js";
 export {MessageComposer} from "./platform/web/ui/session/room/MessageComposer.js";

src/platform/web/ui/session/room/RoomView.js

@@ -23,6 +23,7 @@ import {TimelineLoadingView} from "./TimelineLoadingView.js";
 import {MessageComposer} from "./MessageComposer.js";
 import {RoomArchivedView} from "./RoomArchivedView.js";
 import {AvatarView} from "../../AvatarView.js";
+import {viewClassForEntry} from "./common";
 
 export class RoomView extends TemplateView {
     constructor(options) {
@@ -54,7 +55,7 @@ export class RoomView extends TemplateView {
                 t.div({className: "RoomView_error"}, vm => vm.error),
                 t.mapView(vm => vm.timelineViewModel, timelineViewModel => {
                     return timelineViewModel ?
-                        new TimelineView(timelineViewModel) :
+                        new TimelineView(timelineViewModel, viewClassForEntry) :
                         new TimelineLoadingView(vm);    // vm is just needed for i18n
                 }),
                 t.view(bottomView),

src/platform/web/ui/session/room/TimelineView.ts

@@ -14,9 +14,8 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import type {TileView} from "./common";
-import {viewClassForEntry} from "./common";
 import {ListView} from "../../general/ListView";
+import type {IView} from "../../general/types";
 import {TemplateView, Builder} from "../../general/TemplateView";
 import {IObservableValue} from "../../general/BaseUpdateView";
 import {MissingAttachmentView} from "./timeline/MissingAttachmentView.js";
@@ -25,6 +24,12 @@ import {RedactedView} from "./timeline/RedactedView.js";
 import {SimpleTile} from "../../../../../domain/session/room/timeline/tiles/SimpleTile.js";
 import {BaseObservableList as ObservableList} from "../../../../../observable/list/BaseObservableList";
 
+export interface TileView extends IView {
+    readonly value: SimpleTile;
+} 
+export type TileViewConstructor = new (tile: SimpleTile) => TileView;
+export type ViewClassForEntryFn = (tile: SimpleTile) => TileViewConstructor;
+
 //import {TimelineViewModel} from "../../../../../domain/session/room/timeline/TimelineViewModel.js";
 export interface TimelineViewModel extends IObservableValue {
     showJumpDown: boolean;
@@ -55,13 +60,17 @@ export class TimelineView extends TemplateView<TimelineViewModel> {
     private tilesView?: TilesListView;
     private resizeObserver?: ResizeObserver;
 
+    constructor(vm: TimelineViewModel, private readonly viewClassForEntry: ViewClassForEntryFn) {
+        super(vm);
+    }
+
     render(t: Builder<TimelineViewModel>, vm: TimelineViewModel) {
         // assume this view will be mounted in the parent DOM straight away
         requestAnimationFrame(() => {
             // do initial scroll positioning
             this.restoreScrollPosition();
         });
-        this.tilesView = new TilesListView(vm.tiles, () => this.restoreScrollPosition());
+        this.tilesView = new TilesListView(vm.tiles, () => this.restoreScrollPosition(), this.viewClassForEntry);
         const root = t.div({className: "Timeline"}, [
             t.div({
                 className: "Timeline_scroller bottom-aligned-scroll",
@@ -174,16 +183,14 @@ class TilesListView extends ListView<SimpleTile, TileView> {
 
     private onChanged: () => void;
 
-    constructor(tiles: ObservableList<SimpleTile>, onChanged: () => void) {
+    constructor(tiles: ObservableList<SimpleTile>, onChanged: () => void, private readonly viewClassForEntry: ViewClassForEntryFn) {
         const options = {
             list: tiles,
             onItemClick: (tileView, evt) => tileView.onClick(evt),
         };
         super(options, entry => {
             const View = viewClassForEntry(entry);
-            if (View) {
-                return new View(entry);
-            }
+            return new View(entry);
         });
         this.onChanged = onChanged;
     }
@@ -195,7 +202,7 @@ class TilesListView extends ListView<SimpleTile, TileView> {
 
     onUpdate(index: number, value: SimpleTile, param: any) {
         if (param === "shape") {
-            const ExpectedClass = viewClassForEntry(value);
+            const ExpectedClass = this.viewClassForEntry(value);
             const child = this.getChildInstanceByIndex(index);
             if (!ExpectedClass || !(child instanceof ExpectedClass)) {
                 // shape was updated, so we need to recreate the tile view,

src/platform/web/ui/session/room/common.ts

@@ -24,14 +24,10 @@ import {AnnouncementView} from "./timeline/AnnouncementView.js";
 import {RedactedView} from "./timeline/RedactedView.js";
 import {SimpleTile} from "../../../../../domain/session/room/timeline/tiles/SimpleTile.js";
 import {GapView} from "./timeline/GapView.js";
+import type {TileViewConstructor, ViewClassForEntryFn} from "./TimelineView";
 
-export type TileView = GapView | AnnouncementView | TextMessageView |
-    ImageView | VideoView | FileView | LocationView | MissingAttachmentView | RedactedView;
-
-// TODO: this is what works for a ctor but doesn't actually check we constrain the returned ctors to the types above
-type TileViewConstructor = (this: TileView, SimpleTile) => void;
-export function viewClassForEntry(entry: SimpleTile): TileViewConstructor | undefined {
-    switch (entry.shape) {
+export function viewClassForEntry(vm: SimpleTile): TileViewConstructor {
+    switch (vm.shape) {
         case "gap":
             return GapView;
         case "announcement":
@@ -51,5 +47,7 @@ export function viewClassForEntry(entry: SimpleTile): TileViewConstructor | unde
             return MissingAttachmentView;
         case "redacted":
             return RedactedView;
+        default:
+            throw new Error(`Tiles of shape "${vm.shape}" are not supported, check the tilesCreator function in the view model`);
     }
 }