added dragging multiple items.

10 files changed, 213 insertions, 134 deletions

diff --git a/src/client/northstar/dash-nodes/HistogramBox.tsx b/src/client/northstar/dash-nodes/HistogramBox.tsx
index a968def96..49ebe5ebc 100644
--- a/src/client/northstar/dash-nodes/HistogramBox.tsx
+++ b/src/client/northstar/dash-nodes/HistogramBox.tsx
@@ -54,7 +54,7 @@ export class HistogramBox extends React.Component<FieldViewProps> {
     @action
     dropX = (e: Event, de: DragManager.DropEvent) => {
         if (de.data instanceof DragManager.DocumentDragData) {
-            let h = de.data.draggedDocument.GetT(KeyStore.Data, HistogramField);
+            let h = de.data.draggedDocuments[0].GetT(KeyStore.Data, HistogramField);
             if (h && h != FieldWaiting) {
                 this.HistoOp.X = h.Data.X;
             }
@@ -65,7 +65,7 @@ export class HistogramBox extends React.Component<FieldViewProps> {
     @action
     dropY = (e: Event, de: DragManager.DropEvent) => {
         if (de.data instanceof DragManager.DocumentDragData) {
-            let h = de.data.draggedDocument.GetT(KeyStore.Data, HistogramField);
+            let h = de.data.draggedDocuments[0].GetT(KeyStore.Data, HistogramField);
             if (h && h != FieldWaiting) {
                 this.HistoOp.Y = h.Data.X;
             }
diff --git a/src/client/util/DragManager.ts b/src/client/util/DragManager.ts
index 70b1c9829..9ffe964ef 100644
--- a/src/client/util/DragManager.ts
+++ b/src/client/util/DragManager.ts
@@ -14,9 +14,9 @@ export function setupDrag(_reference: React.RefObject<HTMLDivElement>, docFunc:
 
         document.removeEventListener("pointermove", onRowMove);
         document.removeEventListener('pointerup', onRowUp);
-        var dragData = new DragManager.DocumentDragData(docFunc());
+        var dragData = new DragManager.DocumentDragData([docFunc()]);
         dragData.removeDocument = removeFunc;
-        DragManager.StartDocumentDrag(_reference.current!, dragData);
+        DragManager.StartDocumentDrag([_reference.current!], dragData);
     });
     let onRowUp = action((e: PointerEvent): void => {
         document.removeEventListener("pointermove", onRowMove);
@@ -27,7 +27,7 @@ export function setupDrag(_reference: React.RefObject<HTMLDivElement>, docFunc:
         if (e.button == 0) {
             e.stopPropagation();
             if (e.shiftKey) {
-                CollectionDockingView.Instance.StartOtherDrag(docFunc(), e);
+                CollectionDockingView.Instance.StartOtherDrag([docFunc()], e);
             } else {
                 document.addEventListener("pointermove", onRowMove);
                 document.addEventListener('pointerup', onRowUp);
@@ -101,20 +101,21 @@ export namespace DragManager {
     }
 
     export class DocumentDragData {
-        constructor(dragDoc: Document) {
-            this.draggedDocument = dragDoc;
-            this.droppedDocument = dragDoc;
+        constructor(dragDoc: Document[]) {
+            this.draggedDocuments = dragDoc;
+            this.droppedDocuments = dragDoc;
         }
-        draggedDocument: Document;
-        droppedDocument: Document;
+        draggedDocuments: Document[];
+        droppedDocuments: Document[];
         xOffset?: number;
         yOffset?: number;
         aliasOnDrop?: boolean;
         removeDocument?: (collectionDrop: CollectionView) => void;
         [id: string]: any;
     }
-    export function StartDocumentDrag(ele: HTMLElement, dragData: DocumentDragData, options?: DragOptions) {
-        StartDrag(ele, dragData, options, (dropData: { [id: string]: any }) => dropData.droppedDocument = dragData.aliasOnDrop ? dragData.draggedDocument.CreateAlias() : dragData.draggedDocument);
+
+    export function StartDocumentDrag(eles: HTMLElement[], dragData: DocumentDragData, options?: DragOptions) {
+        StartDrag(eles, dragData, options, (dropData: { [id: string]: any }) => dropData.droppedDocuments = dragData.aliasOnDrop ? dragData.draggedDocuments.map(d => d.CreateAlias()) : dragData.draggedDocuments);
     }
 
     export class LinkDragData {
@@ -125,49 +126,58 @@ export namespace DragManager {
         [id: string]: any;
     }
     export function StartLinkDrag(ele: HTMLElement, dragData: LinkDragData, options?: DragOptions) {
-        StartDrag(ele, dragData, options);
+        StartDrag([ele], dragData, options);
     }
-    function StartDrag(ele: HTMLElement, dragData: { [id: string]: any }, options?: DragOptions, finishDrag?: (dropData: { [id: string]: any }) => void) {
+    function StartDrag(eles: HTMLElement[], dragData: { [id: string]: any }, options?: DragOptions, finishDrag?: (dropData: { [id: string]: any }) => void) {
         if (!dragDiv) {
             dragDiv = document.createElement("div");
             dragDiv.className = "dragManager-dragDiv"
             DragManager.Root().appendChild(dragDiv);
         }
-        const w = ele.offsetWidth, h = ele.offsetHeight;
-        const rect = ele.getBoundingClientRect();
-        const scaleX = rect.width / w, scaleY = rect.height / h;
-        let x = rect.left, y = rect.top;
-        // const offsetX = e.x - rect.left, offsetY = e.y - rect.top;
-
-        let dragElement = ele.cloneNode(true) as HTMLElement;
-        dragElement.style.opacity = "0.7";
-        dragElement.style.position = "absolute";
-        dragElement.style.bottom = "";
-        dragElement.style.left = "";
-        dragElement.style.transformOrigin = "0 0";
-        dragElement.style.zIndex = "1000";
-        dragElement.style.transform = `translate(${x}px, ${y}px) scale(${scaleX}, ${scaleY})`;
-        dragElement.style.width = `${rect.width / scaleX}px`;
-        dragElement.style.height = `${rect.height / scaleY}px`;
-
-        // bcz: PDFs don't show up if you clone them because they contain a canvas.
-        //      however, PDF's have a thumbnail field that contains an image of their canvas.
-        //      So we replace the pdf's canvas with the image thumbnail
-        const doc: Document = dragData["draggedDocument"];
-        if (doc) {
-            var pdfBox = dragElement.getElementsByClassName("pdfBox-cont")[0] as HTMLElement;
-            let thumbnail = doc.GetT(KeyStore.Thumbnail, ImageField);
-            if (pdfBox && pdfBox.childElementCount && thumbnail) {
-                let img = new Image();
-                img!.src = thumbnail.toString();
-                img!.style.position = "absolute";
-                img!.style.width = `${rect.width / scaleX}px`;
-                img!.style.height = `${rect.height / scaleY}px`;
-                pdfBox.replaceChild(img!, pdfBox.children[0])
+
+        let scaleXs: number[] = [];
+        let scaleYs: number[] = [];
+        let xs: number[] = [];
+        let ys: number[] = [];
+
+        const docs: Document[] = dragData instanceof DocumentDragData ? dragData.draggedDocuments : [];
+        let dragElements = eles.map(ele => {
+            const w = ele.offsetWidth, h = ele.offsetHeight;
+            const rect = ele.getBoundingClientRect();
+            const scaleX = rect.width / w, scaleY = rect.height / h;
+            let x = rect.left, y = rect.top;
+            xs.push(x); ys.push(y);
+            scaleXs.push(scaleX); scaleYs.push(scaleY);
+            let dragElement = ele.cloneNode(true) as HTMLElement;
+            dragElement.style.opacity = "0.7";
+            dragElement.style.position = "absolute";
+            dragElement.style.bottom = "";
+            dragElement.style.left = "";
+            dragElement.style.transformOrigin = "0 0";
+            dragElement.style.zIndex = "1000";
+            dragElement.style.transform = `translate(${x}px, ${y}px) scale(${scaleX}, ${scaleY})`;
+            dragElement.style.width = `${rect.width / scaleX}px`;
+            dragElement.style.height = `${rect.height / scaleY}px`;
+
+            // bcz: PDFs don't show up if you clone them because they contain a canvas.
+            //      however, PDF's have a thumbnail field that contains an image of their canvas.
+            //      So we replace the pdf's canvas with the image thumbnail
+            if (docs.length) {
+                var pdfBox = dragElement.getElementsByClassName("pdfBox-cont")[0] as HTMLElement;
+                let thumbnail = docs[0].GetT(KeyStore.Thumbnail, ImageField);
+                if (pdfBox && pdfBox.childElementCount && thumbnail) {
+                    let img = new Image();
+                    img!.src = thumbnail.toString();
+                    img!.style.position = "absolute";
+                    img!.style.width = `${rect.width / scaleX}px`;
+                    img!.style.height = `${rect.height / scaleY}px`;
+                    pdfBox.replaceChild(img!, pdfBox.children[0])
+                }
             }
-        }
 
-        dragDiv.appendChild(dragElement);
+            dragDiv.appendChild(dragElement);
+            return dragElement;
+        });
 
         let hideSource = false;
         if (options) {
@@ -177,62 +187,64 @@ export namespace DragManager {
                 hideSource = options.hideSource();
             }
         }
-        const wasHidden = ele.hidden;
-        if (hideSource) {
-            ele.hidden = true;
-        }
+        eles.map(ele => ele.hidden = hideSource);
+
         const moveHandler = (e: PointerEvent) => {
             e.stopPropagation();
             e.preventDefault();
-            x += e.movementX;
-            y += e.movementY;
             if (dragData instanceof DocumentDragData)
                 dragData.aliasOnDrop = e.ctrlKey || e.altKey;
             if (e.shiftKey) {
                 abortDrag();
-                CollectionDockingView.Instance.StartOtherDrag(doc, { pageX: e.pageX, pageY: e.pageY, preventDefault: () => { }, button: 0 });
+                CollectionDockingView.Instance.StartOtherDrag(docs, { pageX: e.pageX, pageY: e.pageY, preventDefault: () => { }, button: 0 });
             }
-            dragElement.style.transform = `translate(${x}px, ${y}px) scale(${scaleX}, ${scaleY})`;
+            dragElements.map((dragElement, i) => dragElement.style.transform = `translate(${xs[i] += e.movementX}px, ${ys[i] += e.movementY}px) scale(${scaleXs[i]}, ${scaleYs[i]})`);
         };
 
         const abortDrag = () => {
             document.removeEventListener("pointermove", moveHandler, true);
             document.removeEventListener("pointerup", upHandler);
-            dragDiv.removeChild(dragElement);
-            ele.hidden = false;
+            dragElements.map(dragElement => dragDiv.removeChild(dragElement));
+            eles.map(ele => ele.hidden = false);
         }
         const upHandler = (e: PointerEvent) => {
             abortDrag();
-            FinishDrag(ele, e, dragData, options, finishDrag);
+            FinishDrag(eles, e, dragData, options, finishDrag);
         };
         document.addEventListener("pointermove", moveHandler, true);
         document.addEventListener("pointerup", upHandler);
     }
 
-    function FinishDrag(dragEle: HTMLElement, e: PointerEvent, dragData: { [index: string]: any }, options?: DragOptions, finishDrag?: (dragData: { [index: string]: any }) => void) {
-        let parent = dragEle.parentElement;
-        if (parent)
-            parent.removeChild(dragEle);
+    function FinishDrag(dragEles: HTMLElement[], e: PointerEvent, dragData: { [index: string]: any }, options?: DragOptions, finishDrag?: (dragData: { [index: string]: any }) => void) {
+        let removed = dragEles.map(dragEle => {
+            let parent = dragEle.parentElement;
+            if (parent)
+                parent.removeChild(dragEle);
+            return [dragEle, parent];
+        });
         const target = document.elementFromPoint(e.x, e.y);
-        if (parent)
-            parent.appendChild(dragEle);
-        if (!target) {
-            return;
-        }
-        if (finishDrag)
-            finishDrag(dragData);
-
-        target.dispatchEvent(new CustomEvent<DropEvent>("dashOnDrop", {
-            bubbles: true,
-            detail: {
-                x: e.x,
-                y: e.y,
-                data: dragData
+        removed.map(r => {
+            let dragEle: HTMLElement = r[0]!;
+            let parent: HTMLElement | null = r[1];
+            if (parent)
+                parent.appendChild(dragEle);
+        });
+        if (target) {
+            if (finishDrag)
+                finishDrag(dragData);
+
+            target.dispatchEvent(new CustomEvent<DropEvent>("dashOnDrop", {
+                bubbles: true,
+                detail: {
+                    x: e.x,
+                    y: e.y,
+                    data: dragData
+                }
+            }));
+
+            if (options) {
+                options.handlers.dragComplete({});
             }
-        }));
-
-        if (options) {
-            options.handlers.dragComplete({});
         }
         DocumentDecorations.Instance.Hidden = false;
     }
diff --git a/src/client/views/DocumentDecorations.scss b/src/client/views/DocumentDecorations.scss
index 11595aa01..7a43f3087 100644
--- a/src/client/views/DocumentDecorations.scss
+++ b/src/client/views/DocumentDecorations.scss
@@ -32,6 +32,12 @@
     }
 }
 
+.documentDecorations-background {
+    background:lightblue;
+    position: absolute;
+    opacity: 0.1;
+}
+
 //     position: absolute;
 //     display: grid;
 //     z-index: 1000;
diff --git a/src/client/views/DocumentDecorations.tsx b/src/client/views/DocumentDecorations.tsx
index 47098c3b5..faba3b6ea 100644
--- a/src/client/views/DocumentDecorations.tsx
+++ b/src/client/views/DocumentDecorations.tsx
@@ -1,14 +1,14 @@
-import { observable, computed, action } from "mobx";
-import React = require("react");
-import { SelectionManager } from "../util/SelectionManager";
+import { action, computed, observable, trace } from "mobx";
 import { observer } from "mobx-react";
-import './DocumentDecorations.scss'
-import { KeyStore } from '../../fields/KeyStore'
+import { KeyStore } from '../../fields/KeyStore';
+import { ListField } from "../../fields/ListField";
 import { NumberField } from "../../fields/NumberField";
-import { props } from "bluebird";
 import { DragManager } from "../util/DragManager";
+import { SelectionManager } from "../util/SelectionManager";
+import { CollectionView } from "./collections/CollectionView";
+import './DocumentDecorations.scss';
 import { LinkMenu } from "./nodes/LinkMenu";
-import { ListField } from "../../fields/ListField";
+import React = require("react");
 const higflyout = require("@hig/flyout");
 export const { anchorPoints } = higflyout;
 export const Flyout = higflyout.default;
@@ -22,6 +22,7 @@ export class DocumentDecorations extends React.Component {
     private _resizeBorderWidth = 16;
     private _linkButton = React.createRef<HTMLDivElement>();
     @observable private _hidden = false;
+    @observable private _dragging = false;
 
     constructor(props: Readonly<{}>) {
         super(props)
@@ -50,6 +51,50 @@ export class DocumentDecorations extends React.Component {
     public get Hidden() { return this._hidden; }
     public set Hidden(value: boolean) { this._hidden = value; }
 
+    _lastDrag: number[] = [0, 0];
+    onBackgroundDown = (e: React.PointerEvent): void => {
+        document.removeEventListener("pointermove", this.onBackgroundMove);
+        document.addEventListener("pointermove", this.onBackgroundMove);
+        document.removeEventListener("pointerup", this.onBackgroundUp);
+        document.addEventListener("pointerup", this.onBackgroundUp);
+        this._lastDrag = [e.clientX, e.clientY]
+        e.stopPropagation();
+        e.preventDefault();
+    }
+
+    @action
+    onBackgroundMove = (e: PointerEvent): void => {
+        let dragDocView = SelectionManager.SelectedDocuments()[0];
+        const [left, top] = dragDocView.props.ScreenToLocalTransform().inverse().transformPoint(0, 0);
+        let dragData = new DragManager.DocumentDragData(SelectionManager.SelectedDocuments().map(dv => dv.props.Document));
+        dragData.aliasOnDrop = false;
+        dragData.xOffset = e.x - left;
+        dragData.yOffset = e.y - top;
+        dragData.removeDocument = (dropCollectionView: CollectionView) =>
+            dragData.draggedDocuments.map(d => {
+                if (dragDocView.props.RemoveDocument && dragDocView.props.ContainingCollectionView !== dropCollectionView) {
+                    dragDocView.props.RemoveDocument(d);
+                }
+            });
+        this._dragging = true;
+        document.removeEventListener("pointermove", this.onBackgroundMove);
+        document.removeEventListener("pointerup", this.onBackgroundUp);
+        DragManager.StartDocumentDrag(SelectionManager.SelectedDocuments().map(docView => (docView as any)._mainCont!.current!), dragData, {
+            handlers: {
+                dragComplete: action(() => this._dragging = false),
+            },
+            hideSource: true
+        })
+        e.stopPropagation();
+    }
+
+    onBackgroundUp = (e: PointerEvent): void => {
+        document.removeEventListener("pointermove", this.onBackgroundMove);
+        document.removeEventListener("pointerup", this.onBackgroundUp);
+        e.stopPropagation();
+        e.preventDefault();
+    }
+
     onPointerDown = (e: React.PointerEvent): void => {
         e.stopPropagation();
         if (e.button === 0) {
@@ -191,7 +236,6 @@ export class DocumentDecorations extends React.Component {
     // buttonOnPointerUp = (e: React.PointerEvent): void => {
     //     e.stopPropagation();
     // }
-
     render() {
         var bounds = this.Bounds;
         if (this.Hidden) {
@@ -218,25 +262,36 @@ export class DocumentDecorations extends React.Component {
             </Flyout>);
         }
         return (
-            <div id="documentDecorations-container" style={{
-                width: (bounds.r - bounds.x + this._resizeBorderWidth) + "px",
-                height: (bounds.b - bounds.y + this._resizeBorderWidth + 30) + "px",
-                left: bounds.x - this._resizeBorderWidth / 2,
-                top: bounds.y - this._resizeBorderWidth / 2,
-            }}>
-                <div id="documentDecorations-topLeftResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-                <div id="documentDecorations-topResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-                <div id="documentDecorations-topRightResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-                <div id="documentDecorations-leftResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-                <div id="documentDecorations-centerCont"></div>
-                <div id="documentDecorations-rightResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-                <div id="documentDecorations-bottomLeftResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-                <div id="documentDecorations-bottomResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-                <div id="documentDecorations-bottomRightResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
-
-                <div title="View Links" className="linkFlyout" ref={this._linkButton}>{linkButton}</div>
-
-            </div >
+            <div className="documentDecorations">
+                <div className="documentDecorations-background" style={{
+                    width: (bounds.r - bounds.x + this._resizeBorderWidth) + "px",
+                    height: (bounds.b - bounds.y + this._resizeBorderWidth) + "px",
+                    left: bounds.x - this._resizeBorderWidth / 2,
+                    top: bounds.y - this._resizeBorderWidth / 2,
+                    pointerEvents: this._dragging ? "none" : "all",
+                    zIndex: SelectionManager.SelectedDocuments().length > 1 ? 1000 : 0,
+                }} onPointerDown={this.onBackgroundDown} onContextMenu={(e: React.MouseEvent) => { e.preventDefault(); e.stopPropagation() }} >
+                </div>
+                <div id="documentDecorations-container" style={{
+                    width: (bounds.r - bounds.x + this._resizeBorderWidth) + "px",
+                    height: (bounds.b - bounds.y + this._resizeBorderWidth + 30) + "px",
+                    left: bounds.x - this._resizeBorderWidth / 2,
+                    top: bounds.y - this._resizeBorderWidth / 2,
+                }}>
+                    <div id="documentDecorations-topLeftResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+                    <div id="documentDecorations-topResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+                    <div id="documentDecorations-topRightResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+                    <div id="documentDecorations-leftResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+                    <div id="documentDecorations-centerCont"></div>
+                    <div id="documentDecorations-rightResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+                    <div id="documentDecorations-bottomLeftResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+                    <div id="documentDecorations-bottomResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+                    <div id="documentDecorations-bottomRightResizer" className="documentDecorations-resizer" onPointerDown={this.onPointerDown} onContextMenu={(e) => e.preventDefault()}></div>
+
+                    <div title="View Links" className="linkFlyout" ref={this._linkButton}>{linkButton}</div>
+
+                </div >
+            </div>
         )
     }
 }
\ No newline at end of file
diff --git a/src/client/views/Main.tsx b/src/client/views/Main.tsx
index 75855c3d1..6f66f8f38 100644
--- a/src/client/views/Main.tsx
+++ b/src/client/views/Main.tsx
@@ -218,7 +218,8 @@ export class Main extends React.Component {
     focusDocument = (doc: Document) => { }
     noScaling = () => 1;
 
-    get content() {
+    @computed
+    get mainContent() {
         return !this.mainContainer ? (null) :
             <DocumentView Document={this.mainContainer}
                 AddDocument={undefined}
@@ -311,17 +312,17 @@ export class Main extends React.Component {
         }
         return (
             <div id="main-div">
+                <DocumentDecorations />
                 <Measure onResize={(r: any) => runInAction(() => {
                     this.pwidth = r.entry.width;
                     this.pheight = r.entry.height;
                 })}>
                     {({ measureRef }) =>
                         <div ref={measureRef} id="mainContent-div">
-                            {this.content}
+                            {this.mainContent}
                         </div>
                     }
                 </Measure>
-                <DocumentDecorations />
                 <ContextMenu />
                 {this.nodesMenu}
                 {this.miscButtons}
diff --git a/src/client/views/collections/CollectionDockingView.tsx b/src/client/views/collections/CollectionDockingView.tsx
index f123149dd..c6cbc05e7 100644
--- a/src/client/views/collections/CollectionDockingView.tsx
+++ b/src/client/views/collections/CollectionDockingView.tsx
@@ -47,9 +47,10 @@ export class CollectionDockingView extends React.Component<SubCollectionViewProp
         (window as any).React = React;
         (window as any).ReactDOM = ReactDOM;
     }
-    public StartOtherDrag(dragDoc: Document, e: any) {
-        this.AddRightSplit(dragDoc, true).contentItems[0].tab._dragListener.
-            onMouseDown({ pageX: e.pageX, pageY: e.pageY, preventDefault: () => { }, button: 0 })
+    public StartOtherDrag(dragDocs: Document[], e: any) {
+        dragDocs.map(dragDoc =>
+            this.AddRightSplit(dragDoc, true).contentItems[0].tab._dragListener.
+                onMouseDown({ pageX: e.pageX, pageY: e.pageY, preventDefault: () => { }, button: 0 }));
     }
 
     @action
@@ -199,7 +200,7 @@ export class CollectionDockingView extends React.Component<SubCollectionViewProp
             let tab = (e.target as any).parentElement as HTMLElement;
             Server.GetField(docid, action((f: Opt<Field>) => {
                 if (f instanceof Document)
-                    DragManager.StartDocumentDrag(tab, new DragManager.DocumentDragData(f as Document),
+                    DragManager.StartDocumentDrag([tab], new DragManager.DocumentDragData([f as Document]),
                         {
                             handlers: {
                                 dragComplete: action(() => { }),
@@ -265,6 +266,7 @@ export class CollectionDockingView extends React.Component<SubCollectionViewProp
     }
 
     render() {
+        trace();
         return (
             <div className="collectiondockingview-container" id="menuContainer"
                 onPointerDown={this.onPointerDown} onPointerUp={this.onPointerUp} ref={this._containerRef}
@@ -305,6 +307,7 @@ export class DockedFrameRenderer extends React.Component<DockedFrameProps> {
     }
 
     render() {
+        trace();
         if (!this._document)
             return (null);
         var content =
diff --git a/src/client/views/collections/CollectionView.tsx b/src/client/views/collections/CollectionView.tsx
index a1498e0ae..014aa1d8f 100644
--- a/src/client/views/collections/CollectionView.tsx
+++ b/src/client/views/collections/CollectionView.tsx
@@ -113,7 +113,7 @@ export class CollectionView extends React.Component<CollectionViewProps> {
         if (index !== -1) {
             value.splice(index, 1)
 
-            SelectionManager.DeselectAll()
+            //SelectionManager.DeselectAll()
             ContextMenu.Instance.clearItems()
             return true;
         }
diff --git a/src/client/views/collections/CollectionViewBase.tsx b/src/client/views/collections/CollectionViewBase.tsx
index 987f3cb6c..316d20c9d 100644
--- a/src/client/views/collections/CollectionViewBase.tsx
+++ b/src/client/views/collections/CollectionViewBase.tsx
@@ -82,9 +82,9 @@ export class CollectionViewBase extends React.Component<SubCollectionViewProps>
         if (de.data instanceof DragManager.DocumentDragData) {
             if (de.data.aliasOnDrop) {
                 [KeyStore.Width, KeyStore.Height, KeyStore.CurPage].map(key =>
-                    de.data.draggedDocument.GetTAsync(key, NumberField, (f: Opt<NumberField>) => f ? de.data.droppedDocument.SetNumber(key, f.Data) : null));
+                    de.data.draggedDocuments.GetTAsync(key, NumberField, (f: Opt<NumberField>) => f ? de.data.droppedDocument.SetNumber(key, f.Data) : null));
             }
-            let added = this.props.addDocument(de.data.droppedDocument, false);
+            let added = de.data.droppedDocuments.reduce((added, d) => this.props.addDocument(d, false), true);
             if (added && de.data.removeDocument && !de.data.aliasOnDrop) {
                 de.data.removeDocument(this.props.CollectionView);
             }
diff --git a/src/client/views/collections/collectionFreeForm/CollectionFreeFormView.tsx b/src/client/views/collections/collectionFreeForm/CollectionFreeFormView.tsx
index 60fb95ff5..c5178f69d 100644
--- a/src/client/views/collections/collectionFreeForm/CollectionFreeFormView.tsx
+++ b/src/client/views/collections/collectionFreeForm/CollectionFreeFormView.tsx
@@ -77,13 +77,20 @@ export class CollectionFreeFormView extends CollectionViewBase {
                 let screenX = de.x - (de.data.xOffset as number || 0);
                 let screenY = de.y - (de.data.yOffset as number || 0);
                 const [x, y] = this.getTransform().transformPoint(screenX, screenY);
-                de.data.droppedDocument.SetNumber(KeyStore.X, x);
-                de.data.droppedDocument.SetNumber(KeyStore.Y, y);
-                if (!de.data.droppedDocument.GetNumber(KeyStore.Width, 0)) {
-                    de.data.droppedDocument.SetNumber(KeyStore.Width, 300);
-                    de.data.droppedDocument.SetNumber(KeyStore.Height, 300);
-                }
-                this.bringToFront(de.data.droppedDocument);
+                let dragDoc = de.data.draggedDocuments[0];
+                let dragX = dragDoc.GetNumber(KeyStore.X, 0);
+                let dragY = dragDoc.GetNumber(KeyStore.Y, 0);
+                de.data.draggedDocuments.map(d => {
+                    let docX = d.GetNumber(KeyStore.X, 0);
+                    let docY = d.GetNumber(KeyStore.Y, 0);
+                    d.SetNumber(KeyStore.X, x + (docX - dragX));
+                    d.SetNumber(KeyStore.Y, y + (docY - dragY));
+                    if (!d.GetNumber(KeyStore.Width, 0)) {
+                        d.SetNumber(KeyStore.Width, 300);
+                        d.SetNumber(KeyStore.Height, 300);
+                    }
+                    this.bringToFront(d);
+                })
             }
             return true;
         }
diff --git a/src/client/views/nodes/DocumentView.tsx b/src/client/views/nodes/DocumentView.tsx
index 71613ca4f..1195128dc 100644
--- a/src/client/views/nodes/DocumentView.tsx
+++ b/src/client/views/nodes/DocumentView.tsx
@@ -106,7 +106,7 @@ export class DocumentView extends React.Component<DocumentViewProps> {
             if (this.props.isTopMost) {
                 this.startDragging(e.pageX, e.pageY, e.altKey || e.ctrlKey);
             }
-            else CollectionDockingView.Instance.StartOtherDrag(this.props.Document, e);
+            else CollectionDockingView.Instance.StartOtherDrag([this.props.Document], e);
             e.stopPropagation();
         } else {
             if (this.active && !e.isDefaultPrevented()) {
@@ -125,9 +125,7 @@ export class DocumentView extends React.Component<DocumentViewProps> {
         if (this._mainCont.current) {
             this.dropDisposer = DragManager.MakeDropTarget(this._mainCont.current, { handlers: { drop: this.drop.bind(this) } });
         }
-        runInAction(() => {
-            DocumentManager.Instance.DocumentViews.push(this);
-        })
+        runInAction(() => DocumentManager.Instance.DocumentViews.push(this))
         this._reactionDisposer = reaction(
             () => this.props.ContainingCollectionView && this.props.ContainingCollectionView.SelectedDocs.slice(),
             () => {
@@ -149,10 +147,7 @@ export class DocumentView extends React.Component<DocumentViewProps> {
         if (this.dropDisposer) {
             this.dropDisposer();
         }
-        runInAction(() => {
-            DocumentManager.Instance.DocumentViews.splice(DocumentManager.Instance.DocumentViews.indexOf(this), 1);
-
-        })
+        runInAction(() => DocumentManager.Instance.DocumentViews.splice(DocumentManager.Instance.DocumentViews.indexOf(this), 1))
         if (this._reactionDisposer) {
             this._reactionDisposer();
         }
@@ -161,7 +156,7 @@ export class DocumentView extends React.Component<DocumentViewProps> {
     startDragging(x: number, y: number, dropAliasOfDraggedDoc: boolean) {
         if (this._mainCont.current) {
             const [left, top] = this.props.ScreenToLocalTransform().inverse().transformPoint(0, 0);
-            let dragData = new DragManager.DocumentDragData(this.props.Document);
+            let dragData = new DragManager.DocumentDragData([this.props.Document]);
             dragData.aliasOnDrop = dropAliasOfDraggedDoc;
             dragData.xOffset = x - left;
             dragData.yOffset = y - top;
@@ -170,7 +165,7 @@ export class DocumentView extends React.Component<DocumentViewProps> {
                     this.props.RemoveDocument(this.props.Document);
                 }
             }
-            DragManager.StartDocumentDrag(this._mainCont.current, dragData, {
+            DragManager.StartDocumentDrag([this._mainCont.current], dragData, {
                 handlers: {
                     dragComplete: action(() => { }),
                 },