JobTitleList Help
Help is available for each task,
or you can go straight to the JobTitleList
source code to see a solution.
Task 1
Create an Applet to hold one instance of JobTitleList so you
can test the component.
You need to create a class separate from your JobTitleList class.
You can call it JobTitleListTest. In this class, create
an instance of JobTitleList and add it to the container.
import java.awt.*;
public class JobTitleListTest extends java.applet.Applet {
public void init() {
JobTitleList test = new JobTitleList("Test");
add(test);
}
}
Task 2
Create class JobTitleList as a subclass of FormElement.
public class JobTitleList extends FormElement {
...
}
Task 3
In class JobTitleList, create a centered Label and a List below. Set the List so that multiple selections are not allowed.
You have to create a constructor to initialize the components needed by
your compound component, and to add them to the current Container.
In this case, the Container is a Panel because FormElement subclasses Panel:
class JobTitleList extends FormElement {
protected List list;
protected String label = "Job Title";
public JobTitleList() {
list = new List(5,false);
// add a bunch of items to the list
list.addItem("President");
list.addItem("CEO/CFO");
list.addItem("Vice President");
list.addItem("Manager");
list.addItem("CTO");
list.addItem("Engineer");
list.addItem("Designer");
list.addItem("Marketing");
list.addItem("Programmer");
list.addItem("Consultant");
list.addItem("Scientist");
list.addItem("Support Staff");
list.addItem("Slacker");
list.addItem("Webmaster");
// put the label above the List.
setLayout(new BorderLayout());
add("North", new Label(label, Label.CENTER));
add("Center", list);
}
...
}
label and choice are instance variables so that other
methods in this class will have access to them.
Task 4
Implement the method isEmpty of FormElement to return true if the List has a selected element.
When a List has no selected element, getSelectedIndex returns -1.
public boolean isEmpty() {
return list.getSelectedIndex() == -1;
}
Task 5
Implement the method getContents of FormElement to return the Label and the currently selected element of the List.
public String getContents() {
return label + " " + choice.getSelectedItem();
}
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