Always create a model with an empty cell

jupyterlab · Dec 20, 2019 · 01493cd · 01493cd
1 parent b54f4e6
commit 01493cd
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Showing 2 changed files with 9 additions and 6 deletions.
diff --git a/packages/notebook/src/model.ts b/packages/notebook/src/model.ts
@@ -285,6 +285,10 @@ export class NotebookModel extends DocumentModel implements INotebookModel {
    */
   initialize(): void {
     super.initialize();
+    if (!this.cells.length) {
+      let factory = this.contentFactory;
+      this.cells.push(factory.createCodeCell({}));
+    }
     this.cells.clearUndo();
   }
 

diff --git a/packages/notebook/src/panel.ts b/packages/notebook/src/panel.ts
@@ -69,13 +69,12 @@ export class NotebookPanel extends DocumentWidget<Notebook, INotebookModel> {
         return;
       }
 
-      // If the notebook model is empty (new file), set it to edit mode.
-      if (this.content.model.cells.length === 0) {
-        // Wait for an animation frame so the spinner is hidden and the
-        // widget can be focused.
-        requestAnimationFrame(() => {
+      // Set the document edit mode on initial open if it looks like a new document.
+      if (this.content.widgets.length === 1) {
+        let cellModel = this.content.widgets[0].model;
+        if (cellModel.type === 'code' && cellModel.value.text === '') {
           this.content.mode = 'edit';
-        });
+        }
       }
     });
   }