How to assign a value to the viewcriteria attribute from backing bean ?

Question

Hi,
I have a readonly VO with the following query
select attr1,attr2, attr3, attr4
from sometable
I have a view criteria in the above VO something like
attr1=
and attr2=
I have dragged and dropped this criteria on a Status.jsff page as query panel with table. So the user can search the records by manually entering the values in the query panel. Also, there is another page Main.jsff where, if the user clicks on a button, it redirects him to Status.jsff page carrying a numeric value from the Main.jsff page. Now I have to assign this numeric value to "attr1" of the view criteria and execute this VO and show the updated results in the Status.jsff page.
I used the below code :
ViewObject vo = appModule.findViewObject("VOName");
ViewCriteria criteria = vo.getViewCriteriaManager().getViewCriteria("CriteriaName");
criteria.getVariableManager().setVariableValue("attr1", numericValue);
vo.applyViewCriteria(criteria);
vo.executeQuery();
For the above code, i got an error saying that Variable "attr1" not defined in "VOName"
Then i tried setting simple where clause
vo.setWhereClause("attr1="+numericValue);
vo.executeQuery();
For this code, i got an error saying that SQL error during statement preparation.Statement: SELECT * FROM (select attr1 ,attr2,attr3,attr4,from VOName) QRSLT WHERE (attr1=1234)
Please let me know the solution to this problem.

Answer 1

Thank you all for the suggestions.
The idea of Bind Variable works to query the criteria. But I have a Status.jsff page where User can even manually enter the attr1 value and query the results. When I added a bind variable to my VO, one extra input text field with the Bind variable name got added to the query panel in Status.jsff page. Also the table in the page did not show any results even after performing the executeQuery() on the VO(as per the steps explained in the Andrejus blog link that Navneeth has provided)
Please suggest