Hi Christoph,

Thank you for providing the runnable examples.

Please note that in the Grid API autoFitColumn and autoFitColumns are separate methods:

- https://docs.telerik.com/kendo-ui/api/javascript/ui/grid/methods/autofitcolumn

- https://docs.telerik.com/kendo-ui/api/javascript/ui/grid/methods/autofitcolumns

While the autoFitColumn is present in the TreeList API, the autoFitColumns is not yet supported.

For example, if you try to use the autoFitColumn method in the Grid, the same way as in the TreeList, the result will be the same. In the Dojo example linked here, I used your Dojo with the Treelist from your last reply but replaced the component with the Grid. As you will see, using the same approach both components have the same result. As mentioned previously when the autoFitColumn method is used you need to remove the width from the columns configuration of the component.

In order to have the same result in TreeList as in the Grid, the TreeList component should provide the same method (autoFitColumns). With the above said I am changing the status of the bug report to 'Declined'. However, I logged a new Feature request item for providing a built in support for autoFitColumns method and have the same functionality as in the Grid. I would recommend you vote for it in the link below:

- https://feedback.telerik.com/kendo-jquery-ui/1666191-provide-support-for-autofitcolumns-method-in-treelist

I remain at your disposal in case you have any additional questions on the matter. 

Regards,
Neli
Progress Telerik

Hi Christoph,

Could you please provide more details about the scenario and configuration where the Grid autoFitColumn is working and the TreeList does not? I tested the configuration provided in the thread on 27 August and the Grid appearance is the same as in the TreeList in case the widths are not removed from the configuration. You could take a look at the Dojo example linked here - https://dojo.telerik.com/@NeliK/iXOXExEv. I also tested different configurations but i didn`t manage to find a scenario where the behavior of the component is different. Thus, it would be helpful if you could provide more details on the matter.

Looking forward to your reply.

Regards,
Neli
Progress Telerik

Hi Alex,

My name is Nikolay and I will get hold of this thread while Neli is out of the office.

 Auto-fitting all columns at once is a resource-intensive operation and is generally not recommended. A better option is to auto-fit only a few columns that have the most variable content in terms of length.

Alternatively, you can disable scrolling and allow the browser to adjust all column widths automatically, according to their content. 

Dojo demo: https://dojo.telerik.com/ADEMUjEy

I hope this helps.

Regards,
Nikolay
Progress Telerik

Hi Alex,

In order for the autoFitColumn method to work as expected you need to remove the width from the columns configuration. Also you need to ensure that the component is entirely rendered by the time you are using the method. For example, if you need to fit the columns on initialization you can handle the databound event of the TreeList and use the autoFitColumns method there. Below is an example:

 dataBound: function() {
         for (var i = 0; i < this.columns.length; i++) {
                this.autoFitColumn(i);
         }
 },

Here you will find the modified Dojo - https://dojo.telerik.com/@NeliK/UZAXUHeH

Please use the same approach on your side and let me know about the result. 

Regards,
Neli
Progress Telerik

Hello Alex,

Could you please provide more details about your scenario and the structure you are trying to use in the TreeList headers? The example in the API works as expected, thus I will need more information regarding the reported issue. It will be very helpful if you could modify the Dojo example linked here in order to replicate the issue and send it back for a review. 

Looking forward to your reply.

Regards,
Neli
Progress Telerik