Java AWT List

The object of List class represents a list of text items. With the help of the List class, user can choose either one item or multiple items. It inherits the Component class.

AWT List class Declaration

1. public class List extends Component implements ItemSelectable, Accessible  

AWT List Class Constructors

Sr. no.	Constructor	Description
1.	List()	It constructs a new scrolling list.
2.	List(int row_num)	It constructs a new scrolling list initialized with the given number of rows visible.
3.	List(int row_num, Boolean multipleMode)	It constructs a new scrolling list initialized which displays the given number of rows.

Methods Inherited by the List Class

The List class methods are inherited by following classes:

• java.awt.Component
• java.lang.Object

List Class Methods

Sr. no.	Method name	Description
1.	void add(String item)	It adds the specified item into the end of scrolling list.
2.	void add(String item, int index)	It adds the specified item into list at the given index position.
3.	void addActionListener(ActionListener l)	It adds the specified action listener to receive action events from list.
4.	void addItemListener(ItemListener l)	It adds specified item listener to receive item events from list.
5.	void addNotify()	It creates peer of list.
6.	void deselect(int index)	It deselects the item at given index position.
7.	AccessibleContext getAccessibleContext()	It fetches the accessible context related to the list.
8.	ActionListener[] getActionListeners()	It returns an array of action listeners registered on the list.
9.	String getItem(int index)	It fetches the item related to given index position.
10.	int getItemCount()	It gets the count/number of items in the list.
11.	ItemListener[] getItemListeners()	It returns an array of item listeners registered on the list.
12.	String[] getItems()	It fetched the items from the list.
13.	Dimension getMinimumSize()	It gets the minimum size of a scrolling list.
14.	Dimension getMinimumSize(int rows)	It gets the minimum size of a list with given number of rows.
15.	Dimension getPreferredSize()	It gets the preferred size of list.
16.	Dimension getPreferredSize(int rows)	It gets the preferred size of list with given number of rows.
17.	int getRows()	It fetches the count of visible rows in the list.
18.	int getSelectedIndex()	It fetches the index of selected item of list.
19.	int[] getSelectedIndexes()	It gets the selected indices of the list.
20.	String getSelectedItem()	It gets the selected item on the list.
21.	String[] getSelectedItems()	It gets the selected items on the list.
22.	Object[] getSelectedObjects()	It gets the selected items on scrolling list in array of objects.
23.	int getVisibleIndex()	It gets the index of an item which was made visible by method makeVisible()
24.	void makeVisible(int index)	It makes the item at given index visible.
25.	boolean isIndexSelected(int index)	It returns true if given item in the list is selected.
26.	boolean isMultipleMode()	It returns the true if list allows multiple selections.
27.	protected String paramString()	It returns parameter string representing state of the scrolling list.
28.	protected void processActionEvent(ActionEvent e)	It process the action events occurring on list by dispatching them to a registered ActionListener object.
29.	protected void processEvent(AWTEvent e)	It process the events on scrolling list.
30.	protected void processItemEvent(ItemEvent e)	It process the item events occurring on list by dispatching them to a registered ItemListener object.
31.	void removeActionListener(ActionListener l)	It removes specified action listener. Thus it doesn't receive further action events from the list.
32.	void removeItemListener(ItemListener l)	It removes specified item listener. Thus it doesn't receive further action events from the list.
33.	void remove(int position)	It removes the item at given index position from the list.
34.	void remove(String item)	It removes the first occurrence of an item from list.
35.	void removeAll()	It removes all the items from the list.
36.	void replaceItem(String newVal, int index)	It replaces the item at the given index in list with the new string specified.
37.	void select(int index)	It selects the item at given index in the list.
38.	void setMultipleMode(boolean b)	It sets the flag which determines whether the list will allow multiple selection or not.
39.	void removeNotify()	It removes the peer of list.

Java AWT List Example

In the following example, we are creating a List component with 5 rows and adding it into the Frame.

ListExample1.java

1. // importing awt class  
2. import java.awt.*;    
3.   
4. public class ListExample1  
5. {    
6.     // class constructor   
7.      ListExample1() {    
8.      // creating the frame  
9.         Frame f = new Frame();   
10.        // creating the list of 5 rows   
11.         List l1 = new List(5);   
12.   
13.         // setting the position of list component   
14.         l1.setBounds(100, 100, 75, 75);    
15.   
16.         // adding list items into the list  
17.         l1.add("Item 1");    
18.         l1.add("Item 2");    
19.         l1.add("Item 3");    
20.         l1.add("Item 4");    
21.         l1.add("Item 5");    
22.   
23.         // adding the list to frame  
24.         f.add(l1);   
25.   
26.         // setting size, layout and visibility of frame  
27.         f.setSize(400, 400);    
28.         f.setLayout(null);    
29.         f.setVisible(true);    
30.      }    
31.   
32. // main method  
33. public static void main(String args[])    
34. {    
35.    new ListExample1();    
36. }    
37. }    

Output:

Java AWT List Example with ActionListener

In the following example, we are creating two List components, a Button and a Label and adding them into the frame. Here, we are generating an event on the button using the addActionListener(ActionListener l) method. On clicking the button, it displays the selected programming language and the framework.

ListExample2.java

1. // importing awt and event class  
2. import java.awt.*;    
3. import java.awt.event.*;    
4.   
5. public class ListExample2    
6. {    
7.     // class constructor  
8.      ListExample2() {   
9.      // creating the frame   
10.         Frame f = new Frame();   
11.        // creating the label which is final   
12.         final Label label = new Label();   
13.   
14.         // setting alignment and size of label           
15.         label.setAlignment(Label.CENTER);    
16.         label.setSize(500, 100);    
17.   
18.         // creating a button   
19.         Button b = new Button("Show");  
20.   
21.         // setting location of button    
22.         b.setBounds(200, 150, 80, 30);   
23.   
24.         // creating the 2 list objects of 4 rows  
25.         // adding items to the list using add()   
26.         // setting location of list components  
27.         final List l1 = new List(4, false);    
28.         l1.setBounds(100, 100, 70, 70);    
29.         l1.add("C");    
30.         l1.add("C++");    
31.         l1.add("Java");    
32.         l1.add("PHP");    
33.   
34.   
35.         final List l2=new List(4, true);    
36.         l2.setBounds(100, 200, 70, 70);    
37.         l2.add("Turbo C++");    
38.         l2.add("Spring");    
39.         l2.add("Hibernate");    
40.         l2.add("CodeIgniter");   
41.   
42.         // adding List, Label and Button to the frame   
43.         f.add(l1);  
44.         f.add(l2);  
45.         f.add(label);  
46.         f.add(b);    
47.   
48.         // setting size, layout and visibility of frame  
49.         f.setSize(450,450);    
50.         f.setLayout(null);    
51.         f.setVisible(true);    
52.   
53.         // generating event on the button  
54.         b.addActionListener(new ActionListener() {    
55.          public void actionPerformed(ActionEvent e) {         
56.           String data = "Programming language Selected: "+l1.getItem(l1.getSelectedIndex());    
57.           data += ", Framework Selected:";    
58.           for(String frame:l2.getSelectedItems()) {    
59.                    data += frame + " ";    
60.           }    
61.           label.setText(data);    
62.           }    
63.          });            
64. }    
65.   
66. // main method  
67. public static void main(String args[])    
68. {    
69.    new ListExample2();    
70. }    
71. }    

Output: