u can implement it though its a bit complex
take a top level wrapper object [NPE with a boolean attr]dataview and put the data grid2 into that.
now pass this object to the microflow which gets the data for datagrid 2 .
create low lever wrapper object[againNPE with a boolean attr] for each row and link then to the objects .
link the low level wrappers to toplevel wrapper.
use the boolean to render the check boxes for each row..
use top level boolean to control the select all.
now if a action is triggered u can pass the top level wrapper there and fetch all the objects[low level wrapper] which have checkbox ticked and from them get all the actual objects u want to process.
now if some