Hi all
I am very new to spring MVC and I am having a problem. I have a drop
down
list in my web form. i am able to create a new entry without any
problem.
but when I try to update the value of the form, it doesn't selected the
value from the drop down list.( this is very annoying, so I have to
choose
the value again for the drop down list every time).
I have tried to find out what cause it and I couldn't find out why.
here is my code.
in the BidFormController.java
protected Map<String, List<Operator>> referenceData(HttpServletRequest
request){
List<Operator> list = operatorManager.getAll();
Map<String, List<Operator>> map = new HashMap<String,
List<Operator>>();
map.put("operators", list);
return map;
}
protected Object formBackingObject(HttpServletRequest request)throws
Exception {
String id = request.getParameter("id");
if (id != null && request.getMethod().equalsIgnoreCase("get")){
Bid bid = bidManager.get(new Long(id));
return bid;
}
return new Bid();
}
public void initBinder(HttpServletRequest request,
ServletRequestDataBinder
binder){
//super.initBinder(request, binder);
StringToObjectCustomEditor propertyEditor = new
StringToObjectCustomEditor();
propertyEditor.setGenreicManager(operatorManager);
binder.registerCustomEditor(Operator.class, propertyEditor);
}
in bidForm.jsp
<form:select path="operator">
<form:option value="" label="--Please Select" />
<form:options items="${operators}" itemValue="id" itemLabel="name"/>
</form:select>
in StringToObjectCustomEditor.java
/**
* this class is mainly converting the string(the ID in the string
form) to
Object
* the Object must extends the #link{TanBaseObject}.
* */
import java.beans.PropertyEditorSupport;
import com.tantalus.app.model.bid.TanBaseObject;
import com.tantalus.app.service.GenericManager;
/**
* this class can only convert Object that extends TanBaseObject
* @author ben.li
*
*/
public class StringToObjectCustomEditor extends PropertyEditorSupport {
@SuppressWarnings("unchecked")
private GenericManager genericManager = null;
@SuppressWarnings("unchecked")
public GenericManager getGenericManager(){
if (genericManager == null ) {
throw new RuntimeException("Didn't set GenericManager");
}
return genericManager;
}
@SuppressWarnings("unchecked")
public void setGenreicManager(GenericManager genericManager){
this.genericManager = genericManager;
}
@SuppressWarnings("unchecked")
public void setAsText(String text){
if ("".equals(text)){
setValue(null);
}else {
setValue(genericManager.get(new Long(text)));
}
}
public String getAsText(){
TanBaseObject to = (TanBaseObject) getValue();
if (to == null || to.getId() == null){
return null;
}else {
TanBaseObject operator = (TanBaseObject) getValue();
return "" + operator.getId();
}
}
@SuppressWarnings("unchecked")
protected Object convertElement(Object element){
if ( element != null){
Long id = new Long((String)element);
TanBaseObject object = (TanBaseObject)
genericManager.get(id);
return object;
}
return null;
}
}
Can someone please help me which part I did wrong?
Thanks in advance.
