I read from time to time close requirements about the buttons in the navirator bar. Mostly it's the following requirements

• to make standard navigator buttons visible or hidden dynamically (see here an example)
• to enable/disable navigator button (like Edit/Delete) based on the current selected row (see here an example)
• include the id of the current selected row as the additional parameter of the onClickButton callback function of the navButtonAdd.
• include in navButtonAdd some simple tests which allow to skip adding of the button if the same button (with the same buttonicon for example) already exist. In the way 

Mostly first two requirements seems me interesting. So I suggest the following:

1. to change the current behavior of the navGrid creation. One can create all standard buttons in the navigator bar, but hide the buttons having false setting.
2. with respect of call navGrid at the second time one can ignore all other parameters excepting boolean parameters edit, add, del, search, refresh and view. One can use the second navGrid call to make the corresponding buttons visible or hide there. In the same way one can add new boolean "visible" property to navButtonAdd and allows multiple call navButtonAdd to change the visibility of the custom button. If the second call you don't like, one can provide another method which would allow to hide or to show the standard navigator icons.
3. show Edit and Delete navigator buttons disabled per default and enable there if the current selected row is editable:
   
4. provide callback functions which allows to enable any button based of the selected row (like beforeSelectRow which return true or false can be used to allow to select rows).
5. provide methods which can be used to explicitly disable/enable any button from the navigator toolbar.

It seems to me that the suggestions are very common and the changes which I suggest could be interesting to all jqGrid users

Best regards
Oleg