Update a datatable row using the rowKey

[lg900]

I want to ajax update a single datatable row, given the rowKey, when the data changes on the server side. I can already update the whole table, that works no problem, but the table contains lots of data so ajax updating it is quite expensive.

On the client side I can select the relevant tr with this, for example:

$('tr[data-rk="3"]');

Is there a way of doing this on the server with PrimeFaces.current().ajax().update( ... ) ?

[melloware]

You can use @row(n) search expression which does just that - it updates the nth row in a table. In order to update the current row, you need to pass row index as an argument. Set rowIndexVar="rowIdx" attribute on <p:dataTable> and then:

<p:commandButton ... update="@form:visitTable:@row(#{rowIdx})" />

See the docs: https://primefaces.github.io/primefaces/14_0_0/#/core/searchexpression?id=primefaces-additional-keywords

[lg900]

Maybe I wasn't completely clear but I can't get the ajax update to work from the server backend in Java.

This works (but it ajax updates the whole table):
PrimeFaces.current().ajax().update( "mainForm:dataTableComponent:dataTable" );

This does not work (in my application 0 is replaced with the correct row index):
PrimeFaces.current().ajax().update( "mainForm:dataTableComponent:dataTable:@row(0)" );

I could in theory do it in the client front end - the backend can also trigger the client via a websocket to "do things". But I couldn't figure out how to get the client to just "go and ajax update this particular row in the datatable". The documentation recommended using a remoteCommand, but I couldn't work out how to get the remote command to:

update="@form:visitTable:@row(myJavaScriptVariable)"

where the important bit is myJavaScriptVariable, which contains the row index.

I even tried puting a remote command in each row of the datatable - which it refused to do because it said the parent was not an instance of UIData.

Do you have any ideas how to get the server side code working, or to get the client javascript (which is outside of the individual row scope in the websocket callback) to ajax update a specific row?

Any hints would be really appreciated :)

(Primefaces 14.0.6)

[melloware]

Actually row looks like it can be used server side capable. let me test it