Need a better explanation of the "breadcrumbs" widget in Service Portal

[Bob McGill1]

Is there a better explanation on how the breadcrumbs widget works in Service Portal? The documentation page https://docs.servicenow.com/bundle/london-servicenow-platform/page/build/service-portal/concept/brea... is VERY uninformative about how the widget works and how to customize it. 

The only thing that page says is: "The breadcrumbs widget does not have instance options. It displays information based on where a page is located in a portal." What does that even mean? Is there a hidden option or table somewhere that shows the "location" of a page? Is there a hierarchy chart?

I am not the only one that has this issue, as the forums have several posts on how to customize the behavior of the breadcrumbs widget to insert custom pages in the list.

Where do the default pages update the breadcrumbs widget? How?  

It would be helpful if the developer site had a little more information. Does anyone out there have a good understanding of how the breadcrumbs widget works on the default pages and can shed some light?

Thanks.

[Syvo]

Hey Bob,

That has been a pain in my hat for a few days at one time so I sympathize. I'll try to summarize what I understood, and perhaps make an article about it later.

On most pages of the OOB portal, you just have a breadcrumb instance that sits on the top of the page. It's static, and basically displays "Home > Current page". Note that for some customers, that won't be enough and you'll need to make it more complete by using the same technic as the second case below.

On more elaborate pages that require navigation in categories for example, ie catalogs and knowledge bases, you can see the breadcrumbs make a lot more sense and can display something like "Home > Catalog > Category 1 > Category 2 > ... > Item". This is done by the widgets on the page. Look at the server code, you should see a part where it builds an array of objects into data.breadcrumbs. Then the object is passed to the client controller, which is going to send it along with an event that is picked up by the breadcrumbs widget.

HTH, let us know if you have a more specific question.

Sylvain

[Bob McGill1]

Thank you for a very clearly written explanation of what is happening. I would very much like to see your article if you do write one.

I guess my biggest frustration was that it is the widgets that build the breadcrumbs. I thought there was some information hidden in the page.

So - since widgets control the breadcrumb, is it possible that they could have a collision and produce unreliable breadcrumbs? (If you have 2 widgets on the same page that are updating the breadcrumbs.)

[Syvo]

I think if two widgets emit the update breadcrumbs event on the same page, the latest should prevail.

You can search for the name of the event, "sp.update.breadcrumbs", in your widgets client controllers.