Drag canvas but the canvas not moving

Hi, Walter.
I run into another issue. I suppose the default behavior is that when a user drags the canvas, it should be move as the cursor move.
But my code doesn’t have this expected behavior.

const { Diagram, GraphObject, TreeLayout, Spot } = go
const $ = GraphObject.make;
const treeLayout = $(
TreeLayout,
{
angle: 90,
arrangement: TreeLayout.ArrangementVertical,
treeStyle: TreeLayout.StyleLayered,
arrangementSpacing: new Size(0, 35),
},
)

const myDiagram = $(
Diagram,
diagramId,
{
layout: treeLayout,
isReadOnly: false,
allowHorizontalScroll: false,
allowVerticalScroll: false,
allowZoom: true,
allowSelect: true,
contentAlignment: Spot.TopCenter,
minScale: 0.5,
maxScale: 1,
initialScale: 0.85,
“undoManager.isEnabled”: true, // enable undo & redo
},
)

Pls give me some hints. Thank u.

These properties should prevent scrolling, and therefore prevent panning.

Thanks, Walter.
It’s caused by a line of code:
myDiagram.toolManager.panningTool.isEnabled = false;
It’s written by someone else and I didn’t notice before.
After I remove this code, the diagram works fine.