编辑可编辑数据表时丢失数据（JSF2）

I'm starting to code a little cookbook. Therefor i've created a page to add some menusteps, a menustep should describe how to cook the menu step by step. I have a datatable containing a list of MenuSteps. The user can click a commandLink to add/delete a new step. The Bean adds or removes a MenuStep of the list and rerender the datatable with ajax. That works great, except I lost all the data given to the two inputText fields for the steps. They are all blank after I add or delete a row of my datatable.I'm starting to code a little cookbook. Therefo