expose onDidScroll in list/trees

src/vs/base/browser/ui/list/listView.ts

@@ -180,6 +180,8 @@ export class ListView<T> implements ISpliceable<T>, IDisposable {
 	readonly onDidChangeContentHeight: Event<number> = Event.latch(this._onDidChangeContentHeight.event);
 	get contentHeight(): number { return this.rangeMap.size; }
 
+	readonly onDidScroll: Event<void>;
+
 	// private _onDragStart = new Emitter<{ element: T, uri: string, event: DragEvent }>();
 	// readonly onDragStart = this._onDragStart.event;
 
@@ -234,6 +236,7 @@ export class ListView<T> implements ISpliceable<T>, IDisposable {
 
 		this.disposables = [this.rangeMap, this.gesture, this.scrollableElement, this.cache];
 
+		this.onDidScroll = Event.signal(this.scrollableElement.onScroll);
 		this.scrollableElement.onScroll(this.onScroll, this, this.disposables);
 		domEvent(this.rowsContainer, TouchEventType.Change)(this.onTouchChange, this, this.disposables);
 

src/vs/base/browser/ui/list/listWidget.ts

@@ -1080,6 +1080,7 @@ export class List<T> implements ISpliceable<T>, IDisposable {
 		return Event.map(this._onPin.event, indexes => this.toListEvent({ indexes }));
 	}
 
+	get onDidScroll(): Event<void> { return this.view.onDidScroll; }
 	get onMouseClick(): Event<IListMouseEvent<T>> { return this.view.onMouseClick; }
 	get onMouseDblClick(): Event<IListMouseEvent<T>> { return this.view.onMouseDblClick; }
 	get onMouseMiddleClick(): Event<IListMouseEvent<T>> { return this.view.onMouseMiddleClick; }

src/vs/base/browser/ui/tree/abstractTree.ts

@@ -636,6 +636,8 @@ export abstract class AbstractTree<T, TFilterData, TRef> implements IDisposable
 	private _onDidUpdateOptions = new Emitter<IAbstractTreeOptions<T, TFilterData>>();
 	readonly onDidUpdateOptions = this._onDidUpdateOptions.event;
 
+	get onDidScroll(): Event<void> { return this.view.onDidScroll; }
+
 	get onDidChangeFocus(): Event<ITreeEvent<T>> { return Event.map(this.view.onFocusChange, asTreeEvent); }
 	get onDidChangeSelection(): Event<ITreeEvent<T>> { return Event.map(this.view.onSelectionChange, asTreeEvent); }
 	get onDidOpen(): Event<ITreeEvent<T>> { return Event.map(this.view.onDidOpen, asTreeEvent); }

src/vs/base/browser/ui/tree/asyncDataTree.ts

@@ -263,6 +263,8 @@ export class AsyncDataTree<TInput, T, TFilterData = void> implements IDisposable
 
 	protected readonly disposables: IDisposable[] = [];
 
+	get onDidScroll(): Event<void> { return this.tree.onDidScroll; }
+
 	get onDidChangeFocus(): Event<ITreeEvent<T>> { return Event.map(this.tree.onDidChangeFocus, asTreeEvent); }
 	get onDidChangeSelection(): Event<ITreeEvent<T>> { return Event.map(this.tree.onDidChangeSelection, asTreeEvent); }
 	get onDidOpen(): Event<ITreeEvent<T>> { return Event.map(this.tree.onDidOpen, asTreeEvent); }