Merge branch 'master' into linking-anh

1 files changed, 9 insertions, 6 deletions

diff --git a/src/client/views/collections/CollectionPileView.tsx b/src/client/views/collections/CollectionPileView.tsx
index 6baf633dd..bc1407c53 100644
--- a/src/client/views/collections/CollectionPileView.tsx
+++ b/src/client/views/collections/CollectionPileView.tsx
@@ -1,12 +1,12 @@
-import { action, computed } from "mobx";
+import { action, computed, IReactionDisposer, reaction } from "mobx";
 import { observer } from "mobx-react";
 import { Doc, HeightSym, WidthSym } from "../../../fields/Doc";
 import { NumCast, StrCast } from "../../../fields/Types";
-import { emptyFunction, setupMoveUpEvents, returnTrue } from "../../../Utils";
+import { emptyFunction, returnTrue, setupMoveUpEvents } from "../../../Utils";
 import { DocUtils } from "../../documents/Documents";
 import { SelectionManager } from "../../util/SelectionManager";
 import { SnappingManager } from "../../util/SnappingManager";
-import { UndoManager, undoBatch } from "../../util/UndoManager";
+import { undoBatch, UndoManager } from "../../util/UndoManager";
 import { CollectionFreeFormView } from "./collectionFreeForm/CollectionFreeFormView";
 import "./CollectionPileView.scss";
 import { CollectionSubView } from "./CollectionSubView";
@@ -15,6 +15,7 @@ import React = require("react");
 @observer
 export class CollectionPileView extends CollectionSubView(doc => doc) {
     _originalChrome: any = "";
+    _disposers: { [name: string]: IReactionDisposer } = {};
 
     componentDidMount() {
         if (this.layoutEngine() !== "pass" && this.layoutEngine() !== "starburst") {
@@ -22,9 +23,14 @@ export class CollectionPileView extends CollectionSubView(doc => doc) {
         }
         this._originalChrome = this.layoutDoc._chromeHidden;
         this.layoutDoc._chromeHidden = true;
+
+        // pileups are designed to go away when they are empty.  
+        this._disposers.selected = reaction(() => this.childDocs.length,
+            (num) => !num && this.props.ContainingCollectionView?.removeDocument(this.props.Document));
     }
     componentWillUnmount() {
         this.layoutDoc._chromeHidden = this._originalChrome;
+        Object.values(this._disposers).forEach(disposer => disposer?.());
     }
 
     layoutEngine = () => StrCast(this.Document._pileLayoutEngine);
@@ -107,9 +113,6 @@ export class CollectionPileView extends CollectionSubView(doc => doc) {
             this._undoBatch?.end();
             this._undoBatch = undefined;
             SnappingManager.SetIsDragging(false);
-            if (!this.childDocs.length) {
-                this.props.ContainingCollectionView?.removeDocument(this.props.Document);
-            }
         }, emptyFunction, e.shiftKey && this.layoutEngine() === "pass", this.layoutEngine() === "pass" && e.shiftKey); // this sets _doubleTap
     }