It took some time to find out the reason of the problem.
1) About my question above which is
Would be good to add parameter to onLoadError which should describe reason of error.
It seems like documentation for Datagrid is not completely correct, becase
onLoadError has parameter which helps to understand the reason of the problem.
But in documentation I see "
none"
2) About my initial problem.
onLoadError: function(arguments){alert('Load error:'+arguments.responseText);}
Using the following code I have found that page does not get any data because of SQL problem on server side.
It happened because I expect $_POST['page'] to be above 0 if it is set.
In my case $_POST['page'] was
0.
I see $_POST['page'] set to zero when I load something, then load nothing and then try to load something again.
Can you look into this two issues?
Thanks