How To Initialize a JComboBox Whose Items are added Dynamically?

Question

I have Created a JComboBox and its item are being added dynamically through a LinkedList, how to initialize its selected value.

Suppose "list" contains A->B->C->D->null

I want to intialize the ComboBox selected index with B (i.e 2nd Item In the list).

I have tried to do it as below

ComboBox.setSelectedIndex(1);

but I am getting Exception setSelectedIndex: 1 out of bound

JComboBox ComboBox= new JComboBoX();
LinkedList List = new LinkedList();

getListDataFromDataBase();
//After this List Contains A->B->C->D->null

for(int i=1;i<=List.getSize();i++)
{
    Object Item = List.getValueAt(i);
    ComboBox.addItem(Item);
}

ComboBox.setSelectedIndex(1);

Answer 1

Make sure elements are added into the comboBox, using addItem().

Here's a small snippet:

import javax.swing.JComboBox;
import javax.swing.JFrame;

public class Demo {

  public static void main(String[] a) {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JComboBox jComboBox1 = new JComboBox();
    jComboBox1.addItem("Item 0");
    jComboBox1.addItem("Item 1");
    jComboBox1.addItem("Item 2");
    jComboBox1.addItem("Item 3");
    jComboBox1.addItem("Item 4");
    jComboBox1.addItem("Item 5");

    Object cmboitem = jComboBox1.getSelectedItem();
    System.out.println(cmboitem);

    frame.add(jComboBox1);

    jComboBox1.setSelectedIndex(4);
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}

EDIT

Adding from a linkedList

for(int i = 0; i < linkedList.size(); i++)
   comboBox.addItem(linkedList.get(i).toString());