After call function treeModel.update(), the scrollbar moves to top

[ulymor]

Hi, I recently discovered this bug. If I call function treeModel.update() inside event activate on tree the scrollbar scrolls to the top of the tree.

I want to load more children using node 'Show more'. 'Show more' is the last visible leaf. After click on 'Show more' node I added child nodes to parent node model and call treeModel.update() function

public onActivate($event: any) { if ($event.node.data.isShowMore) { const parent = $event.node.parent.data as TestItemNode; if (parent) { parent.loadMore(); //add TestItemNode[] to children collection this.treeComponent.treeModel.update(); } } }

Current behaviour:

After call this.treeComponent.treeModel.update() the scrollbar scrolls to the top

Expected behaviour:

After call function this.treeComponent.treeModel.update() the scrollbar stays on the same position

Reproduce

• Expand tree

• Scroll to the bottom of the page

• Click on child node at the bottom of the tree

Results:

• Tree is scrolled to the top

Expected results

• Scrollbar stayed on the same position

Note: If I click on 'End' title and call treeModel.update() the scrollbar isn't jumping

https://stackblitz.com/edit/angular-okp7ix

Additional Info

• Paste your package.json - "angular-tree-component": "^8.2.0" (everything you can see in the StackBlitz repro)
• Which browser - Chrome 71, FF 65

[phhbr]

Related #704

[philipphutterer]

add scrollOnActivate: false to treeOptions might be an option. don't know why you actually want to have scroll onActivate but that's how you can disable it.