Add a layer to a viewer with drag and drop

glue_jupyterlab/glue_session.py

@@ -349,6 +349,16 @@ def _init_ydoc(self) -> None:
             ydoc=self._sessionYDoc,
         )
 
+    def add_viewer_layer(self, tab_name: str, viewer_name: str, data_name: str) -> None:
+        """Add a layer with new dataset to a viewer"""
+        viewer = (
+            self._viewers.get(tab_name, {}).get(viewer_name, {}).get("widget", None)
+        )
+        if not viewer:
+            return
+        data = self._data[data_name]
+        viewer.add_data(data)
+
     def add_data(self, file_path: str) -> None:
         """Add a new data file to the session"""
         relative_path = Path(file_path).relative_to(Path(self._path).parent)

src/commands.ts

@@ -19,6 +19,8 @@ export namespace CommandIDs {
   export const openControlPanel = 'glue-control:open-control-panel';
 
   export const closeControlPanel = 'glue-control:close-control-panel';
+
+  export const addViewerLayer = 'glue-control:add-viewer-layer';
 }
 
 export interface INewViewerArgs {

src/leftPanel/plugin.ts

@@ -229,6 +229,23 @@ function addCommands(
       controlModel.clearConfig();
     }
   });
+
+  commands.addCommand(CommandIDs.addViewerLayer, {
+    execute: async args => {
+      const kernel = controlModel.currentSessionKernel();
+      if (kernel === undefined) {
+        // TODO Show an error dialog
+        return;
+      }
+
+      const code = `
+      GLUE_SESSION.add_viewer_layer("${args.tab}", "${args.viewer}", "${args.data}")
+      `;
+
+      const future = kernel.requestExecute({ code }, false);
+      await future.done;
+    }
+  });
 }
 
 export const controlPanel: JupyterFrontEndPlugin<void> = {

src/viewPanel/gridStackItem.ts

@@ -1,6 +1,8 @@
 import { Panel, Widget } from '@lumino/widgets';
 import { Toolbar, ToolbarButton, closeIcon } from '@jupyterlab/ui-components';
+import { Message } from '@lumino/messaging';
 import { ISignal, Signal } from '@lumino/signaling';
+import { DATASET_MIME } from '../types';
 
 export class GridStackItem extends Panel {
   constructor(options: GridStackItem.IOptions) {
@@ -10,12 +12,13 @@ export class GridStackItem extends Panel {
     this.addClass('grid-stack-item');
     this.addClass('glue-item');
 
-    const { cellIdentity, cell, itemTitle = '', pos, size } = options;
+    const { cellIdentity, cell, itemTitle = '', pos, size, tabName } = options;
     this._cellOutput = cell;
     this.cellIdentity = cellIdentity;
     this._pos = pos;
     this._size = size;
     this._title = itemTitle;
+    this._tabName = tabName;
 
     const content = new Panel();
     content.addClass('grid-stack-item-content');
@@ -63,10 +66,35 @@ export class GridStackItem extends Panel {
     this._size = value;
   }
 
+  get tabName(): string {
+    return this._tabName;
+  }
+
+  set tabName(value: string) {
+    this._tabName = value;
+  }
   get changed(): ISignal<GridStackItem, GridStackItem.IChange> {
     return this._changed;
   }
 
+  protected onAfterAttach(msg: Message): void {
+    super.onAfterAttach(msg);
+    this.node.addEventListener('drop', this._ondrop.bind(this));
+  }
+
+  protected onBeforeDetach(msg: Message): void {
+    this.node.removeEventListener('drop', this._ondrop.bind(this));
+    super.onBeforeDetach(msg);
+  }
+
+  private async _ondrop(event: DragEvent) {
+    const datasetId = event.dataTransfer?.getData(DATASET_MIME);
+    if (!datasetId) {
+      return;
+    }
+    this._changed.emit({ action: 'layer', dataLayer: datasetId });
+  }
+
   private _createToolbar(itemTitle: string): Toolbar {
     const toolbar = new Toolbar();
     toolbar.node.addEventListener('click', () => {
@@ -97,7 +125,7 @@ export class GridStackItem extends Panel {
   private _size: number[];
   private _title: string;
   private _cellOutput: Widget;
-
+  private _tabName: string;
   private _changed: Signal<GridStackItem, GridStackItem.IChange>;
 }
 
@@ -108,9 +136,11 @@ export namespace GridStackItem {
     itemTitle?: string;
     pos: number[];
     size: number[];
+    tabName: string;
   }
 
   export interface IChange {
-    action: 'close' | 'lock' | 'edit';
+    action: 'close' | 'lock' | 'edit' | 'layer';
+    dataLayer?: string;
   }
 }

src/viewPanel/sessionWidget.ts

@@ -96,8 +96,14 @@ export class SessionWidget extends BoxPanel {
   }
 
   private async _ondrop(event: DragEvent) {
-    const datasetId = event.dataTransfer?.getData(DATASET_MIME);
+    const target = event.target as HTMLElement;
+    const viewer = target.closest('.grid-stack-item.glue-item');
+    // No-op if the target is a viewer, it will be managed by the viewer itself.
+    if (viewer) {
+      return;
+    }
 
+    const datasetId = event.dataTransfer?.getData(DATASET_MIME);
     const items: IDict<string> = {
       Histogram: CommandIDs.new1DHistogram,
       '1D Profile': CommandIDs.new1DProfile,

src/viewPanel/tabLayout.ts

@@ -318,6 +318,21 @@ export class TabLayout extends Layout {
       gridItem: item as any
     });
   }
+
+  /**
+   * Request to add a layer with a dataset to the viewer.
+   *
+   * @param item - the viewer where to add a layer.
+   * @param dataName - the data to add to the viewer.
+   */
+  private _addViewerLayer(item: GridStackItem, dataName: string): void {
+    this._commands.execute(CommandIDs.addViewerLayer, {
+      tab: item.tabName,
+      viewer: item.cellIdentity,
+      data: dataName
+    });
+  }
+
   /**
    * Handle change-event messages sent to from gridstack.
    */
@@ -376,6 +391,12 @@ export class TabLayout extends Layout {
       case 'edit':
         this._handleEdit(sender);
         break;
+      case 'layer':
+        if (!change.dataLayer) {
+          return;
+        }
+        this._addViewerLayer(sender, change.dataLayer);
+        break;
       default:
         break;
     }

src/viewPanel/tabView.ts

@@ -153,7 +153,8 @@ export class TabView extends Widget {
         cell: out,
         itemTitle: itemTitle.match(/($[a-z])|[A-Z][^A-Z]+/g)?.join(' '),
         pos: viewerData.pos,
-        size: viewerData.size
+        size: viewerData.size,
+        tabName: tabName
       });
       const cellOutput = item.cellOutput as SimplifiedOutputArea;
       if (this._context) {