Re: UISelectMany (Problem Resolved). Mr. Weber, Regarding Cleaning Multiple Selections

[Caroline Jen <ji...@yahoo.com>]

Hi Volker,

     Thanks a lot.  I have an answer to the question
that I posted earlier.

     In the submit() method that is invoked by an
action, I nullify the selectedItems after the
StringBuffer is created.  This way, the multiple
selections that were made previously will not show up
(not be highlighted) on the screen when I re-run the
application.

     Thanks again.  Have a nice day.

Warm Regards,
Caroline

--- Caroline Jen <ji...@yahoo.com> wrote:

> Hi Volker,
> 
>      I asked a wrong question in my previous post. 
> Sorry.
> 
>      Your code works fine.  It cleans the multiple
> selections "internally".  
> 
>      I observe a problem:
> 
> After a user submits his/her multiple selections,
> which is an action (instead of an action listener),
> I
> display the files that he/she has selected.  Then, I
> close the browser.
> 
>      While the server is still running, I run the
> same
> application again.  And I see the previously
> selected
> items are highlighted in the list box on my screen.
> 
>      What should I do to resolve this problem?  I
> mean
> how to erase the selections visually after the
> 'action' takes place?  See
> 
> 						<h:commandButton value="View Data Files ..."
> type="submit" style="width: 180px"
>
action="#{fileManagementBean.displaySelectedFiles}"/>
> 
> The "type' attribute in the commandButton has to
> have
> a value "submit".
> 
>      The cleaning multiple selections is easier. 
> the
> command button that has an action listener to invoke
> the clear( ActionEvent e ) method can have a 'type'
> attibute with its value being "reset" to clean the
> previous selections visually.
> 
> --Caroline
> 
> --- Volker Weber <us...@weber-oldenburg.de>
> wrote:
> 
> > Hi Caroline,
> > 
> > 
> > 
> > Caroline Jen wrote:
> > ...
> > > Meanwhile, would you mind advising:
> > > 
> > 
> > You want to clear the selected Items?
> > 
> > just clear or null the field in the bean.
> > public void clear(ActionEvent e)
> > {
> >   FacesContext facesContext =
> >       FacesContext.getCurrentInstance();
> >   ValueBinding vb =
> > e.getComponent().getValueBinding();
> >   if (vb != null) {
> >     vb.setValue(facesContext, null);
> >   }
> > }
> > 
> > 
> > 
> > > 1. How do I deliver each element of the Object[]
> > > selectedItems into this method:
> > > 
> > > public void clear(ActionEvent e) 
> > > {
> > >     FacesContext facesContext =
> > > FacesContext.getCurrentInstance();
> > >     UIViewRoot uiViewRoot =
> > > facesContext.getViewRoot();
> > > 
> > >     // Here, I want to iterating through the
> > Object[]
> > >     if (selectedItems[i] instanceof
> > > EditableValueHolder)
> > >     {
> > 
> > this can never happen, selectedItems[i] is not an
> > instance of
> > EditableValueHolder !
> > selectedItems[i] is the first argument of
> SelectItem
> > constructor:
> > String in my example.
> > 
> > >     EditableValueHolder evh =
> > (EditableValueHolder)
> > > selectedItems[i];
> > >     evh.setSubmittedValue(null);
> > 
> > This has no effect in application phase.
> > just setting a variable to null and throwing away
> > afterwards.
> > 
> > >     } 
> > > }
> > > 
> > > The code snippet above is a draft.  I am
> uncertain
> > if
> > > I am doing it right.
> > > 
> > 
> > 
> > 
> > > 2. The multiple selections made by user are in
> an
> > > Object array (i.e. Object[] selectedItems).  How
> > do I
> > > retrieve the values from this Object array (I
> > think
> > 
> > Just fetch them from your bean or via ValueBinding
> > from your Component.
> > 
> > > that the values retrieved will be a String[] if
> I
> > am
> > > not terribly wrong.) to be sent to the database?
> > 
> > The type is the array type of the objects used to
> > create the
> > selectItems, in my example Strings.
> > 
> > I attached updated TestBean.java and test.jsp with
> > examples.
> > 
> > Regards
> > Volker Weber
> > -- 
> > Don't answer to From: address!
> > Mail to this account are droped if not recieved
> via
> > mailinglist.
> > To contact me direct create the mail address by
> > concatenating my forename to my senders domain.
> > > package org.apache.myfaces.examples;
> > 
> > import javax.faces.component.UISelectMany;
> > import javax.faces.component.UISelectItems;
> > import javax.faces.model.SelectItem;
> > import javax.faces.event.ActionEvent;
> > import javax.faces.context.FacesContext;
> > import javax.faces.el.ValueBinding;
> > import java.util.List;
> > import java.util.ArrayList;
> > 
> > public class TestBean {
> > 
> >   private UISelectMany selectMany;
> > 
> >   private Object[] selectedItems;
> > 
> >   public TestBean() {
> >     selectMany = new UISelectMany();
> >     selectMany.setId("selectMany");
> > 
> >     UISelectItems items = new UISelectItems();
> >     items.setId("selectManyItems");
> >     items.setValue(createSelectItems());
> > 
> >     selectMany.getChildren().add(items);
> >   }
> > 
> >   private Object createSelectItems() {
> >     List items = new ArrayList();
> >     for (int i = 0; i < 10; i++){
> >       items.add(new SelectItem("item" + i, "Item
> No.
> > " + i));
> >     }
> >     return items;
> >   }
> > 
> >   public UISelectMany getSelectMany() {
> >     return selectMany;
> >   }
> > 
> >   public void setSelectMany(UISelectMany
> selectMany)
> > {
> >     this.selectMany = selectMany;
> >   }
> > 
> >   public Object[] getSelectedItems() {
> >     return selectedItems;
> >   }
> > 
> >   public void setSelectedItems(Object[]
> > selectedItems) {
> 
=== message truncated ===



	
		
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