feat: loading state on startup

package.json

@@ -1439,7 +1439,7 @@
             "view/item/context": [
                 {
                     "command": "deepnote.revealInExplorer",
-                    "when": "view == deepnoteExplorer",
+                    "when": "view == deepnoteExplorer && viewItem != loading",
                     "group": "inline@2"
                 }
             ]

src/notebooks/deepnote/deepnoteTreeDataProvider.ts

@@ -7,7 +7,8 @@ import {
     workspace,
     RelativePattern,
     Uri,
-    FileSystemWatcher
+    FileSystemWatcher,
+    ThemeIcon
 } from 'vscode';
 import * as yaml from 'js-yaml';
 
@@ -26,6 +27,8 @@ export class DeepnoteTreeDataProvider implements TreeDataProvider<DeepnoteTreeIt
 
     private fileWatcher: FileSystemWatcher | undefined;
     private cachedProjects: Map<string, DeepnoteProject> = new Map();
+    private isInitialScanComplete: boolean = false;
+    private initialScanPromise: Promise<void> | undefined;
 
     constructor() {
         this.setupFileWatcher();
@@ -38,6 +41,8 @@ export class DeepnoteTreeDataProvider implements TreeDataProvider<DeepnoteTreeIt
 
     public refresh(): void {
         this.cachedProjects.clear();
+        this.isInitialScanComplete = false;
+        this.initialScanPromise = undefined;
         this._onDidChangeTreeData.fire();
     }
 
@@ -51,6 +56,15 @@ export class DeepnoteTreeDataProvider implements TreeDataProvider<DeepnoteTreeIt
         }
 
         if (!element) {
+            if (!this.isInitialScanComplete) {
+                if (!this.initialScanPromise) {
+                    this.initialScanPromise = this.performInitialScan();
+                }
+
+                // Show loading item
+                return [this.createLoadingTreeItem()];
+            }
+
             return this.getDeepnoteProjectFiles();
         }
 
@@ -61,6 +75,28 @@ export class DeepnoteTreeDataProvider implements TreeDataProvider<DeepnoteTreeIt
         return [];
     }
 
+    private createLoadingTreeItem(): DeepnoteTreeItem {
+        const loadingItem = new DeepnoteTreeItem(
+            DeepnoteTreeItemType.Loading,
+            { filePath: '', projectId: '' },
+            null,
+            TreeItemCollapsibleState.None
+        );
+        loadingItem.label = 'Scanning for Deepnote projects...';
+        loadingItem.iconPath = new ThemeIcon('loading~spin');
+        return loadingItem;
+    }
+
+    private async performInitialScan(): Promise<void> {
+        try {
+            await this.getDeepnoteProjectFiles();
+        } finally {
+            this.isInitialScanComplete = true;
+            this.initialScanPromise = undefined;
+            this._onDidChangeTreeData.fire();
+        }
+    }
+
     private async getDeepnoteProjectFiles(): Promise<DeepnoteTreeItem[]> {
         const deepnoteFiles: DeepnoteTreeItem[] = [];
 

src/notebooks/deepnote/deepnoteTreeItem.ts

@@ -6,7 +6,8 @@ import type { DeepnoteProject, DeepnoteNotebook } from '../../platform/deepnote/
  */
 export enum DeepnoteTreeItemType {
     ProjectFile = 'projectFile',
-    Notebook = 'notebook'
+    Notebook = 'notebook',
+    Loading = 'loading'
 }
 
 /**
@@ -25,16 +26,20 @@ export class DeepnoteTreeItem extends TreeItem {
     constructor(
         public readonly type: DeepnoteTreeItemType,
         public readonly context: DeepnoteTreeItemContext,
-        public readonly data: DeepnoteProject | DeepnoteNotebook,
+        public readonly data: DeepnoteProject | DeepnoteNotebook | null,
         collapsibleState: TreeItemCollapsibleState
     ) {
         super('', collapsibleState);
 
         this.contextValue = this.type;
-        this.tooltip = this.getTooltip();
-        this.iconPath = this.getIcon();
-        this.label = this.getLabel();
-        this.description = this.getDescription();
+
+        // Skip initialization for loading items as they don't have real data
+        if (this.type !== DeepnoteTreeItemType.Loading) {
+            this.tooltip = this.getTooltip();
+            this.iconPath = this.getIcon();
+            this.label = this.getLabel();
+            this.description = this.getDescription();
+        }
 
         if (this.type === DeepnoteTreeItemType.Notebook) {
             this.resourceUri = this.getNotebookUri();