Question

when i go to "layout" tab then swimlane and click heirarchic to organise my chart all the typed words disappear?

Comments

That sure is strange and should of course not be the case (and it is not for me). For this reason I would like to ask:

Which version of yEd are you using (see "Help" -> "About")?

On which operating system are you using yEd?

Please upload a GraphML file with your diagram before applying the hierachic swimlane layout (see How to upload files to yEd Q&A? for instructions on uploading files). Otherwise it is almost impossible for us to reproduce and understand your problem. Since this is a public forum, please make sure nothing you upload contains sensitive information.

Please upload the file "settings.xml" from your yEd profile directory (see "Help" -> "About" for the profile directory location) as well.

Answer 1

http://yed.yworks.com/support/qa/?qa=blob&qa_blobid=4531384216836449434

Here is my graph before applying the hierachic swimlane layout

Comments

Well, running the hierarchic swimlane algorithm with default settings except for orientation left to right on your diagram works as intended for me (yEd 3.18.1.1, Java 1.8.0_181, Ubuntu 16.04).
Maybe you are using a specific combination of settings that triggers an incorrect behavior. Thus we really, really need your settings.xml file as well. Moreover, if you could also upload a version of your diagram after you have run the hierarchic swimlane algorithm that would help as well.

Answer 2

It just occurred to me that your labels may be disappearing simply because the editor automatically zooms out to make the arranged diagram fit into the editor area after a layout calculation.

Do your labels reappear if you click the "1:1" button in the tool bar?

yEd does not display labels below certain zoom levels. This is a performance optimization because displaying text is expensive and at very small zoom levels text is not readable anyways so it does not make sense to perform the expensive operation. However, it is possible to turn off this optimization. To do that, open "File" -> "Preferences", go to tab "Display" and set the value for option "Paint Details Threshold" to "0".

Comments

setting the threshold to 0 has worked
Thank you very much