ensureVisible() throws an exception

[TymekParticipant]

I use jqWidgets with Angular 6 and when I call function ensureVisible() I get exceotion:
ERROR TypeError: Cannot read property ‘top’ of undefined
at init.position (jqxcore.js:14)
at b.(:4200/anonymous function).ensureVisible (http://localhost:4200/vendor.js:69105:11971)

This is my code:

@ViewChild('tree') tree: jqxTreeComponent;
...

const item = ...
if (item !== null) {
   this.tree.expandItem(item);
   this.tree.ensureVisible(item);
   this.tree.selectItem(item);
}

Html:

<jqxTree #tree [width]="'100%'" [height]="'97%'" [source]="treeSource" (onExpand)="onExpand($event)" (onCollapse)="onCollapse($event)"
    (onItemClick)="onItemClick($event)" [allowDrag]="false" [allowDrop]="false" [theme]="theme">
  </jqxTree>

Expanding and selecting work correctly. How can I solve this problem?

[MartinParticipant]

Hello Tymek,

This exception comes from the “item” that you pass to the ensureVisible() function.
Try passing the HTMLElement of the item you want to ensure visible.
For example:

let item = document.getElementById("10");
 this.tree.ensureVisible(item);

or

let selectedItem = this.tree.getSelectedItem();
 this.tree.ensureVisible(selectedItem.element);

It depends on how you get the item.
If this does not work, please, send a larger example of your code.

Best Regards,
Martin

jQWidgets Team
http://www.jqwidgets.com/

[TymekParticipant]

Thanks, using “item.element” instead od “item” works.

[Author]

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