Alternative for cloning in LWUIT Component object - java-me

Question

Situation:-
In my code I have to use the LWUIT Component object for the listview controls. The controls are dynamic and hence can be in any number.
Right now I am creating Component objects according to the controls(in numbers) i.e.- for every control to be created first the Component object is creating.
This process slows down the rendering of the listview when the controls are increasing.
Solution:-
If I create the Component object and use it in a loop for all the controls it is taking the reference of the object and hence displays all the listview items(controls) with the same data.
Now I am able to think of one last option of Cloning my object and using it to create the controls.
Problem:-
But I can't find any way in LWUIT by which I can achieve the copying of object.
What can be the alternatives in LWUIT to solve this problem?
P.S.-The listview items are of same type, but with different data.

Answer 1

Use a List component and the Renderer design pattern to create a "rubber stamp" component where you can display a large number of elements easily. See an explanation of this in the Codename One blog.
Create these classes first :
public class ListUtil {
private Vector data = new Vector();
private Content[] contents;
public ListUtil(Vector vData)
{
data = vData;
contents = new Content[vData.size()];
}
public List createList(Display display, CListCell renderer, ActionListener listener)
{
CList theList;
for(int i = 0; i < data.size(); i++)
{
contents[i] = new Content(String.valueOf(data.elementAt(i)));
}
theList = new CList(display, contents, renderer, listener);
return theList;
}
}
public class Content
{
private String row;
public Content(String row)
{
this.row = row;
}
public String getRow()
{
return (row);
}
}
public class CListCell extends Container implements ListCellRenderer {
private Label focus = new Label("");
public CListCell()
{
super();
// create and add the components here among the components which will display data
}
public Component getListCellRendererComponent(List list, Object value, int index, boolean isSelected)
{
Content entry = null;
if (value instanceof Content)
entry = (Content)value;
componentDisplayingDataAddedIntoThisListCellRenderer.setText(entry.getRow());
return this;
}
public Component getListFocusComponent(List arg0)
{
return focus;
}
}
public class CList extends List {
private Display disp;
public CList(Display display, Object[] data, CListCell renderer, ActionListener actionListener)
{
super(data);
setListCellRenderer(renderer);
setIgnoreFocusComponentWhenUnfocused(true);
addActionListener(actionListener);
setScrollAnimationSpeed(getScrollAnimationSpeed()/4);
disp = display;
}
public void pointerReleased(int x,int y)
{
if (isEnabled() && hasFocus())
super.pointerReleased(x, y);
}
public void keyReleased(int keyCode)
{
if (isEnabled() && hasFocus())
{
if (disp.getGameAction(keyCode) == Display.GAME_FIRE)
pointerReleased(getX(),getY());
else
super.keyReleased(keyCode);
}
}
}
To create your List and add it to a Form :
public class myForm extends Form implements ActionListener
{
private Vector listSource = // your vector of data
private CListCell renderer = new CListCell();
private List theList = (new ListUtil(listSource)).createList(Display.getInstance(),renderer, this);
...
public void actionPerformed(ActionEvent evt)
{
if (evt.getSource() == theList)
doSomething();
}
}