JDeveloper 11.1.1.3: Best Practice for Checkboxes in Table

Question

Hi there,
I'm having problems with checkboxes inside the table component.
Can someone please fill me in as to what the best practice is to use checkboxes inside a table ?
In the database, we are storing values Y and N.
Thanks,
Mark

Answer 1

Hi Mark,
I suppose you are talking about ADF Faces applications. If so, then I have two prefered approaches tested and used in real practice:
*1) First approach: Create a simple converter, define it in the faces-config.xml and set it in the <af:selectBooleanCheckbox> tags' "converter" attribute, for example:*
package mypackage;
import javax.faces.application.FacesMessage;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.convert.ConverterException;
public class BooleanYNConverter implements Converter {
  public BooleanYNConverter() {
  public Object getAsObject(FacesContext facesContext, UIComponent uiComponent, String string) {
    if (string==null) return null;
    String s = string.trim();
    if (s.length()==0) return null;
    if (s.equalsIgnoreCase("true")) return "Y";
    if (s.equalsIgnoreCase("false")) return "N";
    FacesMessage errorMessage = new FacesMessage(FacesMessage.SEVERITY_ERROR,
        "Cannot convert " + string + " to Y/N. It must be either true or false",
        "Cannot convert " + string + " to Y/N. It must be either true or false" );
    throw new ConverterException(errorMessage);
  public String getAsString(FacesContext facesContext, UIComponent uiComponent, Object object) {
    if (object == null) return "";
    if (object.equals("Y")) return "true";
    if (object.equals("N")) return "false";
    FacesMessage errorMessage = new FacesMessage(FacesMessage.SEVERITY_ERROR,
        "Cannot convert " + object + " to true/false. It must be either Y or N",
        "Cannot convert " + object + " to true/false. It must be either Y or N" );
    throw new ConverterException(errorMessage);
}In faces-config.xml:
  <converter>
    <converter-id>BooleanYNConverter</converter-id>
    <converter-class>mypackage.BooleanYNConverter</converter-class>
  </converter>In JSF page:
<af:selectBooleanCheckbox ... converter="BooleanYNConverter"/>
N.B. If you use this approach, the ViewObject attribute's Control Type should be set to "Default" instead of "Checkbox" (see the attribute's Control Hints section in the dialog box)!
*2) Second approach: In the PageDef define a button binding for Y/N values and map the corresponding item in the table binding to this button binding. In this way you will remap VO attribute's Y/N value to true/false as how the checkbox component expects it. Neither converters nor additional configuration is necessary, but you have to do this on each checkbox field again:*
<?xml version="1.0" encoding="UTF-8" ?>
<pageDefinition xmlns="http://xmlns.oracle.com/adfm/uimodel" version="11.1.1.56.60" id="TestPagePageDef" Package="view.pageDefs">
  <parameters/>
  <executables>
    <variableIterator id="variables"/>
    <iterator Binds="DeptViewRO" RangeSize="25" DataControl="AppModuleDataControl" id="DeptViewROIterator"/>
  </executables>
  <bindings>
    <tree IterBinding="DeptViewROIterator" id="DeptViewRO">
      <nodeDefinition DefName="model.DeptViewRO" Name="DeptViewRO0">
        <AttrNames>
          <Item Value="DeptID"/>
          <Item Value="DeptName"/>
          <Item Value="Flag" Binds="MyFlag"/>
        </AttrNames>
      </nodeDefinition>
    </tree>
    <button IterBinding="DeptViewROIterator" StaticList="true" id="MyFlag">
      <AttrNames>
        <Item Value="Flag"/>
      </AttrNames>
      <ValueList>
        <Item Value="Y"/>
        <Item Value="N"/>
      </ValueList>
    </button>
  </bindings>
</pageDefinition>In the sample above the target VO attribute is called Flag. Have a look at the line <tt><Item Value="Flag" Binds="MyFlag"/></tt>. This line does the magic.
Hope I've been a bit helpful.
Dimitar
Edited by: Dimitar Dimitrov on Nov 13, 2010 1:53 PM
There was a little mistake: Instead of BooleanYNConverter I had written BooleanYNCheckbox in the <af:selectBooleanCheckbox> tag.