Where to put the code for dynamically change dataprovider

Question

I have a table bound to dataprovider1 by default ( by the SJC ). In the same page, I also have a dataprovider2 which is for the same fields of the same table of dataprovider1. The only different is to put some criteria on one field ( like F_D1 = '5' ) so that one provider will show all rows, the other just some rows.
The code to change the dataprovider is as follows :
tableRowGroupWorksheet.setValueBinding("sourceData", getApplication().createValueBinding("#{WorksheetPage.dataprovider2}") );
If I put this code into some button_action() and then I click that button, then the page displays the corresponding data just fine.
But if I put this code in either preprocess or prerender, then things seems messed up : the number of pages is for data of dataprovider1, but when I click button Next of the table then it shows the number of pages of dataprovider2. ( I also try to put it in init but this does not help either ).
I need this code to be run when this page is selected but right now it requires me to click on a button :(
The reason I need it runs automatically is because of the logic generated from the previous page.
Thanks for your advive,
Vu

Answer 1

After re-reading the life-cycles of JSF and the injected phases of SJC, I think I know why it does not work when the page is first called. In this case, AplyRequestValue phase is skipped therefore preprocess is never called. Also in this case, the component tree, with binding, validators, ... is only built in the Render Response phase and this phase is right after PreRender is called therefore the binding code I put in prerender is overwritten by Render Response.
When using a button action, the component tree is already built and not rebuit under Render Response, therefore that code is not overwritten. Also in this case, preprocess is called so putting that code under either preprocess or prerender will work.
Please correct me.
Thanks,
Vu