How to check the validation in UI before committing data?

Question

Hi,
I'm using Jdev 11.1.2.1.0 version .
I needed to check whether there is duplication of values in Boolean check box before committing the data into the Database.
But this validation rule is to be checked based on the value selected in the Select One Choice drop down list in the page.
I did it with adding a ValueChangeEvent in the drop down list and checking the values in the Boolean check box. It worked , but only in the case of earlier committed data in the database.
How can i actually verify the data entered in the table in the page before it being committed into the DB ?
Nigel.

Answer 1

Hi,
an improvement to your solution would be to move the major part of your code from the backing bean into a method on the ApplicationModuleImpl file (you create this from the AM editor)
  public boolean checkForDuplicate(){
       ViewObject vo = this.findViewObject("ResponseVO");
       int numRows;
       int j=0;
       numRows = vo.getRowCount();
       String rowValue = "a";
//the part below of your code I don't like at all. Why do you need to increase a flag
//and use an if statement ?
       for (int i=0; i<numRows; i++){
          rowValue = (String)vo.getCurrentRow().getAttribute("ResponseFlag");
          if(rowValue.equals("Y")){                           
              j++;
              if(j>1)
                  return true;
         return false;                           
    }This code you then expose on the AM as a client interface (same AM editor --> Java menu option)
In the PageDef file (double click it to access the visual editor) click the plus icon next to the Bindings header. Choose "Generic Binding" --> method binding and point it to the AM and the exposed method. This creates a method binding "checkForDuplicate"
Change your managed bean code to
  BindingContext bctx = BindingContext.getCurrent();
  BindingContainer bindings = bctx.getCurrentBindingsEntry();
  OperationBinding checkForDuplicate = (OperationBinding ) bindings.get("checkForDuplicate");
  checkForDuplicate.execute();
  boolean isDuplicate =  checkForDuplicate.getResult();            
  if(isDuplicate){
         FacesMessage msg = new FacesMessage(FacesMessage.SEVERITY_ERROR, null, "Two same respones!");
         FacesContext.getCurrentInstance().addMessage(null, msg);
                                           Frank