The document provides an overview of using JFace to build cross-platform user interfaces in Java. It discusses how JFace includes convenience classes for building SWT applications and a framework for displaying and editing business model objects using SWT widgets like TableViewer and TreeViewer. It then walks through an example of using these components to build a to-do list application, including creating model objects, initializing the TableViewer, and implementing the various event handler objects like ContentProvider, LabelProvider, CellEditor, CellModifier, and RowSorter.

1. A simple, productive path to effective
cross-platform interfaces

2.  A bunch of convenience classes for
building SWT applications
◦ ApplicationWindow
◦ Dialog
◦ Wizard
 A framework for displaying and editing
Java business model objects using SWT
◦ TableViewer
◦ TreeViewer
Introduction to Jface| By Rahul Shukla 2

3.  A bunch of convenience classes for
building SWT applications
◦ ApplicationWindow
◦ Dialog
◦ Wizard
 A framework for displaying and editing
Java business model objects using SWT
◦ TableViewer
◦ TreeViewer
Introduction to Jface| By Rahul Shukla 3

4.  Hello, JFace
public class HelloJFace extends ApplicationWindow {
public HelloJFace(Shell parentShell) {
super(parentShell);
setBlockOnOpen(true);
}
public static void main(String[] args) {
(new HelloJFace(null)).open();
}
}
Introduction to Jface| By Rahul Shukla 4

5.  Hello, JFace
Introduction to Jface| By Rahul Shukla 5

6.  Ways to add features to your JFace
application:
◦ Add code to constructor
◦ Override protected methods
◦ Add new methods or classes
Introduction to Jface| By Rahul Shukla 6

7.  Add menu bar, tool bar, status line
public class HelloJFace extends ApplicationWindow
{
public HelloJFace(Shell parentShell) {
super(parentShell);
setBlockOnOpen(true);
}
public static void main(String[] args) {
(new HelloJFace(null)).open();
}
}
Introduction to Jface| By Rahul Shukla 7

8.  Add menu bar, tool bar, status line
public class HelloJFace extends ApplicationWindow {
public HelloJFace(Shell parentShell) {
super(parentShell);
setBlockOnOpen(true);
addMenuBar();
addToolBar(SWT.FLAT);
addStatusLine();
}
public static void main(String[] args) {
(new HelloJFace(null)).open();
}
}
Introduction to Jface| By Rahul Shukla 8

9.  Add application title and icon
protected void configureShell(Shell shell) {
super.configureShell(shell);
shell.setText("Hello, JFace");
shell.setImage(
ImageDescriptor.createFromFile(
HelloJFace.class,
"icons/app.png").createImage());
}
Introduction to Jface| By Rahul Shukla 9

10.  Add menu to menu bar
protected MenuManager createMenuManager() {
MenuManager menuManager = new MenuManager();
menuManager.add(createFileMenu());
return menuManager;
}
private MenuManager createFileMenu() {
MenuManager menu = new MenuManager("&File");
menu.add(new Action() {
public String getText() {
return "E&xit";
}
public void run() {
getShell().close();
} });
return menu;
}
Introduction to Jface| By Rahul Shukla 10

11.  Add button to tool bar
protected ToolBarManager createToolBarManager(
int style)
{
ToolBarManager toolBar = new
ToolBarManager(style);
toolBar.add(new NewAction());
return toolBar;
}
Introduction to Jface| By Rahul Shukla 11

12.  Add private class NewAction for button
private class NewAction extends Action {
public String getText() { return "New"; }
public String getToolTipText() { return "New"; }
public ImageDescriptor getImageDescriptor() {
ImageDescriptor imageDesc =
ImageDescriptor.createFromFile(
HelloJFace.class, "icons/new.png");
return imageDesc;
}
public ImageDescriptor getHoverImageDescriptor() {
ImageDescriptor imageDesc =
ImageDescriptor.createFromFile(
HelloJFace.class, "icons/new-h.png");
return imageDesc;
}
public void run() { // add action code here
}
}
Introduction to Jface| By Rahul Shukla 12

13.  Suppose we really want to build a “To-do”
list...
Introduction to Jface| By Rahul Shukla 13

14.  A bunch of convenience classes for
building SWT applications
◦ ApplicationWindow
◦ Dialog
◦ Wizard
 A framework for displaying and editing
Java business model objects using SWT
◦ TableViewer
◦ TreeViewer
Introduction to Jface| By Rahul Shukla 14

15.  Steps to add to-do list editor to
application
◦ Create TodoList “model” objects
◦ Add TableViewer object to layout
◦ Initialize TableViewer
◦ Set TodoList object as the TableViewer's input
◦ Write (or reuse existing classes) to specify the
following TableViewer event handler objects
 ContentProvider, LabelProvider
 CellEditor, CellModifier
 RowSorter
Introduction to Jface| By Rahul Shukla 15

16.  JFace TableViewer usage
TableViewerTodoList
TreeMapTodo
“input”
Introduction to Jface| By Rahul Shukla 16

17.  JFace TableViewer usage
TableViewerTodoList
Todo
“input”
ContentProvider
LabelProvider
RowSorter
CellEditor
CellModifier
Introduction to Jface| By Rahul Shukla 17

18. ● Steps to add to-do list editor to application
– Create TodoList “model” objects
– Add TableViewer object to layout
– Initialize TableViewer
– Set TodoList object as the TableViewer's input
– Write (or reuse existing classes) to specify the
following TableViewer event handler objects
● ContentProvider, LabelProvider
● CellEditor, CellModifier
● RowSorter
Introduction to Jface| By Rahul Shukla 18

19.  Create TodoList “model” object
public class TodoList implements Serializable {
public static List<Todo> list = new ArrayList<Todo>();
public static void addTodo(Todo todo) {
list.add(todo);
}
}
Introduction to Jface| By Rahul Shukla 19

20.  Steps to add to-do list editor to
application
◦ Create TodoList “model” object
◦ Add TableViewer object to layout
◦ Initialize TableViewer
◦ Set TodoList object as the TableViewer's input
◦ Write (or reuse existing classes) to specify the
following TableViewer event handler objects
 ContentProvider, LabelProvider
 CellEditor, CellModifier
 RowSorter
Introduction to Jface| By Rahul Shukla 20

21.  Add TableViewer object to layout
protected Control createContents(Composite parent)
{
return contents;
}
Introduction to Jface| By Rahul Shukla 21

22.  Add TableViewer object to layout
protected Control createContents(Composite parent) {
GridLayout layout = new GridLayout(1, false);
layout.marginHeight = 20;
layout.marginWidth = 20;
contents.setLayout(layout);
TableViewer viewer = new TableViewer(contents, SWT.BORDER |
SWT.H_SCROLL | SWT.V_SCROLL |
SWT.FULL_SELECTION);
viewer.getTable().setLayoutData(
new GridData(GridData.FILL_BOTH));
return contents;
}
Introduction to Jface| By Rahul Shukla 22

23.  Steps to add to-do list editor to
application
◦ Create TodoList “model” object
◦ Add TableViewer object to layout
◦ Initialize TableViewer
◦ Set TodoList object as the TableViewer's input
◦ Write (or reuse existing classes) to specify the
following TableViewer event handler objects
 ContentProvider, LabelProvider
 CellEditor, CellModifier
 RowSorter
Introduction to Jface| By Rahul Shukla 23

24.  Initialize TableViewer...
protected Control createContents(Composite parent) {
Composite contents = new Blotter(parent, SWT.NULL);
GridLayout layout = new GridLayout(1, false);
layout.marginHeight = 20;
layout.marginWidth = 20;
contents.setLayout(layout);
viewer = new TableViewer(contents, SWT.BORDER |
SWT.H_SCROLL
| SWT.V_SCROLL | SWT.FULL_SELECTION);
viewer.getTable().setLayoutData(new
GridData(GridData.FILL_BOTH));
init();
return contents;
} Introduction to Jface| By Rahul Shukla 24

25.  JFace TableViewer usage
TableViewerTodoList
TreeMapTodo
“input”
ContentProvider
LabelProvider
RowSorter
CellEditor
CellModifier
Introduction to Jface| By Rahul Shukla 25

26.  Implement addProvidersAndEditors()
private void addProvidersAndEditors() {
table.setContentProvider(
new ContentProvider());
table.setLabelProvider(new LabelProvider());
CellEditor[] editors = {
new CheckboxCellEditor(table.getTable()),
new TextCellEditor(table.getTable()),
new TextCellEditor(table.getTable())};
table.setCellEditors(editors);
table.setCellModifier(new CellModifier());
table.setSorter(new RowSorter());
table.setColumnProperties(colNames);
}
Introduction to Jface| By Rahul Shukla 27

27.  Steps to add to-do list editor to
application
◦ Create TodoList “model” object
◦ Add TableViewer object to layout
◦ Initialize TableViewer
◦ Set TodoList object as the TableViewer's input
◦ Write (or reuse existing classes) to specify the
following TableViewer event handler objects
 ContentProvider, LabelProvider
 CellEditor, CellModifier
 RowSorter
Introduction to Jface| By Rahul Shukla 28

28.  Set TodoList as the TableViewer's input
private void init() {
addColumns();
addProviders();
addEditors();
viewer.setInput(TodoList.list);
}
Introduction to Jface| By Rahul Shukla 29

29.  Set TodoList as the TableViewer's input
private void initTable() {
addColumns();
addProvidersAndEditors();
table.setInput(TodoList.theList);
}
private static final String[] colNames =
{ "Done", "Priority", "Description" };
private static final int[] colWeight =
{ 5, 5, 90 };
private static final int COL_DONE = 0;
private static final int COL_PRIORITY = 1;
private static final int COL_DESC = 2;
Introduction to Jface| By Rahul Shukla 30

30.  Steps to add to-do list editor to
application
◦ Create TodoList “model” object
◦ Add TableViewer object to layout
◦ Initialize TableViewer
◦ Set TodoList object as the TableViewer's input
◦ Write (or reuse existing classes) to specify the
following TableViewer event handler objects
 ContentProvider, LabelProvider
 CellEditor, CellModifier
 RowSorter
Introduction to Jface| By Rahul Shukla 31

31.  Implement addProvidersAndEditors()
private void addProviders() {
viewer.setContentProvider(new MyContentProvider());
viewer.setLabelProvider(new MyTableLabelProvider());
}
private void addEditors() {
Table table = viewer.getTable();
CellEditor[] editors = { new
CheckboxCellEditor(table),
new TextCellEditor(table), new TextCellEditor(table)
};
viewer.setCellEditors(editors);
viewer.setCellModifier(new CellModifier(columns,
this));
viewer.setColumnProperties(columns);Introduction to Jface| By Rahul Shukla 32

32.  JFace TableViewer usage
TableViewerTodoList
TreeMapTodo
“input”
ContentProvider
LabelProvider
RowSorter
CellEditor
CellModifier
Introduction to Jface| By Rahul Shukla 33

33.  A closer look at JFace “event handler
objects”
Event Handler When Triggered
ContentProvider On setInput(), refresh(), update()
LabelProvider A cell needs redrawing
CellEditor Edit cell value
CellModifier Fetch editable value / store value
RowSorter On table redraw
Introduction to Jface| By Rahul Shukla 34

34.  A closer look at JFace “event handler
objects”
Event Handler When Triggered
ContentProvider On setInput(), refresh(), update()
LabelProvider A cell needs redrawing
CellEditor Edit cell value
CellModifier Fetch editable value / store value
RowSorter On table redraw
Introduction to Jface| By Rahul Shukla 35

35.  Implementing ContentProvider
private class ContentProvider
implements IStructuredContentProvider
{
public Object[] getElements(
Object inputElement)
{
return ((TodoList)inputElement).toArray();
}
public void dispose() {}
public void inputChanged(Viewer viewer,
Object oldInput, Object newInput) {}
}
Introduction to Jface| By Rahul Shukla 36

36.  JFace TableViewer usage
TableViewerTodoList
TreeMapTodo
“input”
ContentProvider
LabelProvider
RowSorter
CellEditor
CellModifier
Introduction to Jface| By Rahul Shukla 37

37.  A closer look at JFace “event handler
objects”
Event Handler When Triggered
ContentProvider On setInput(), refresh(), update()
LabelProvider A cell needs redrawing
CellEditor Edit cell value
CellModifier Fetch editable value / store value
RowSorter On table redraw
Introduction to Jface| By Rahul Shukla 38

38.  Implementing LabelProvider
private class LabelProvider
implements ITableLabelProvider {
private Image done;
private Image notdone;
public LabelProvider() {
done = ImageDescriptor.createFromFile(
TodoListWindow.class,
"icons/task-done.png").createImage();
notdone = ImageDescriptor.createFromFile(
TodoListWindow.class,
"icons/task-open.png").createImage();
}
// <continued/>...
Introduction to Jface| By Rahul Shukla 39

39.  Implementing LabelProvider
public Image getColumnImage(Object element, int
columnIndex) {
Todo todo = (Todo) element;
switch (columnIndex) {
case 0:
if (todo.isDone())
return ImageDescriptor.createFromFile(HelloJFace.class,
"icons/done.gif").createImage();
else
return null;
default:
return null;
}
}
// <continued/>...
Introduction to Jface| By Rahul Shukla 40

40.  Implementing LabelProvider
public String getColumnText(Object element, int
columnIndex) {
Todo todo = (Todo) element;
switch (columnIndex) {
case 1:
return String.valueOf(todo.getPriority());
case 2:
return String.valueOf(todo.getDesc());
default:
return null;
}
} // <continued/>...
Introduction to Jface| By Rahul Shukla 41

41.  A closer look at JFace “event handler
objects”
Event Handler When Triggered
ContentProvider On setInput(), refresh(), update()
LabelProvider A cell needs redrawing
CellEditor Edit cell value
CellModifier Fetch editable value / store value
RowSorter On table redraw
Introduction to Jface| By Rahul Shukla 42

42.  JFace TableViewer usage
TableViewerTodoList
TreeMap
Todo
“input”
ContentProvider
LabelProvider
RowSorter
CellEditor
CellModifier
Introduction to Jface| By Rahul Shukla 43

43.  JFace TableViewer usage
TableViewerTodoList
Todo
“input”
ContentProvider
LabelProvider
RowSorter
CellEditor
CellModifier
The visible editor
Introduction to Jface| By Rahul Shukla 44

44.  JFace TableViewer usage
TableViewerTodoList
Todo
“input”
ContentProvider
LabelProvider
RowSorter
CellEditor
CellModifier
Translates between
visible editor's
data type and the
model's storage
data type
Introduction to Jface| By Rahul Shukla 45

45.  Implementing CellModifier
private class CellModifier
implements ICellModifier
{
public boolean canModify(Object element, String
property) {
return true;
}
// <continued/>...
Introduction to Jface| By Rahul Shukla 46

46.  Implementing CellModifier
public Object getValue(Object element, String property) {
Todo todo = (Todo) element;
if (property.equals(columns[0])) {
return new Boolean(todo.isDone());
} else if (property.equals(columns[1])) {
return Integer.toString(todo.getPriority());
} else if (property.equals(columns[2])) {
return todo.getDesc();
}
return null;
}
Introduction to Jface| By Rahul Shukla 47

47.  Implementing CellModifier
public void modify(Object element, String property, Object value) {
Item item = (Item) element;
Todo todo = (Todo) item.getData();
if (property.equals(columns[0])) {
boolean val = ((Boolean) value).booleanValue();
todo.setDone(val);
} else if (property.equals(columns[1])) {
int parseInt;
try {
parseInt = Integer.parseInt((String) value);
todo.setPriority(parseInt);
} catch (Exception e) {
MessageDialog.openError(window.getShell(), "Error", value
+ " is not a number");
}
} else if (property.equals(columns[2])) {
todo.setDesc((String) value);
}
window.refresh();
} Introduction to Jface| By Rahul Shukla 48

48.  A closer look at JFace “event handler
objects”
Event Handler When Triggered
ContentProvider On setInput(), refresh(), update()
LabelProvider A cell needs redrawing
CellEditor Edit cell value
CellModifier Fetch editable value / store value
RowSorter On table redraw
Introduction to Jface| By Rahul Shukla 49

49.  Implementing RowSorter
private class RowSorter extends ViewerSorter {
public int compare(Viewer viewer,
Object element1, Object element2) {
Todo t1 = (Todo) element1;
Todo t2 = (Todo) element2;
return t1.getPriority() -
t2.getPriority();
}
}
Introduction to Jface| By Rahul Shukla 50

50.  A closer look at JFace “event handler
objects”
Event Handler When Required
ContentProvider Always
LabelProvider Always
CellEditor If grid is not read-only
CellModifier If grid is not read-only
RowSorter If grid is sorted
Introduction to Jface| By Rahul Shukla 51

51.  So here's what we just built...
Introduction to Jface| By Rahul Shukla 52

52. Any questions?
Question................... ?