Private Set<ID> seltestset(){
    Set<ID> seltestIDSet = new Set<ID>();

        
String stqry = 'Select st.name, st.Testing_Item__c, st.Id From Tests_to_run__c st Where st.Software_Testing__c = :o.id Order By st.Name';
         for (Tests_to_run__c st : Database.query(stqry)){

            seltestIDSet.add(st.Testing_Item__c);}
	    return seltestIDSet; 		
}

 now the issue I have is the o.id, where I get Variable not defined.

well actually o is defined in the costructor : 

    private ApexPages.StandardController controller;
 
    // constructor
    private final Software_Testing__c o;
    public TestSearchController(ApexPages.StandardController stdController) {
         this.o = (Software_Testing__c)stdController.getRecord();       
         }

funny thing is I'm using the same o.id (variable) when saving the records:

//The list of Tests to Run records to insert
        list <Tests_to_run__c> test2runList = new list <Tests_to_run__c>();
        
        for (TestWrapper cw : selectedTests) {
        	test2runList.add(new Tests_to_run__c 
        	                 (Software_Testing__c = o.id,
        	                  Testing_Item__c = cw.cat.id,
        	                  Compulsory__c = cw.cat.Def_Compulsary__c,
        	                  Assigne_to_User__c = cw.cat.Def_Functionality_Owner__c));
        }
        if (test2runList.size() > 0) {
          insert test2runList;
        }
        controller = new ApexPages.StandardController(o);
        return controller.view();

And there I did not get any error.

Any suggestion ?

Thanks

Alex