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SWT , TreeViewer , CellEditor with ComboBox

While using EditingSupport for a treeColumn in a TreeViewer, Is there any way i can just reflect the Changes in the View instead of changing the model and then using getViewer().update(element,null);
Detail:
I want to achieve the following functionality:
Show a tree View with |Object| (ComboBox)property|
Upon selection and clicking on the button i want to show user the summary of changes and then upon clicking confirm i want to apply those changes to the model (Object)
I am using a TreeViewer, Within that i have a column with EditingSupport Enabled.
Whenever I select a value from the ComboBox and click somewhere else (lostFocus kind of ) the Value sets to default.
I have figured out that after SetValue() is called the TreeLabelProvider is again called(using debug points)
Is there any way i can just reflect the Changes in the View instead of changing the model and using getViewer().update(element,null);
Some FYIs :
Package Object contains multiple versions
ContentProvider does the job to fetch the object
LabelProvider gets all the Versions from the package(String[]) and shows the first one.
//Code to Create the UI
// blah
TreeViewerColumn column2 = new TreeViewerColumn(treeViewer, SWT.LEFT);
column2.getColumn().setText("Version");
column2.getColumn().setWidth(130);
treeViewer.setLabelProvider(new PackageUpdateTreeLabelProvider());
EditingSupport exampleEditingSupport = new OperationEditingSupport(
column2.getViewer());
column2.setEditingSupport(exampleEditingSupport);
OperationEditingSupport Class
private class OperationEditingSupport extends EditingSupport {
private ComboBoxCellEditor cellEditor = null;
private OperationEditingSupport(ColumnViewer viewer) {
super(viewer);
cellEditor = new ComboBoxCellEditor(
((TreeViewer) viewer).getTree(), new String[] {},
SWT.READ_ONLY);
}
#Override
protected CellEditor getCellEditor(Object element) {
// TODO Auto-generated method stub
if (element instanceof IPackageInfo) {
IPackageInfo pkg = (IPackageInfo) element;
cellEditor.setItems(PackageMgrUtil.getInstance().getVersions(
(IdmPackage) pkg, false, true));
return cellEditor;
}
return null;
}
#Override
protected boolean canEdit(Object element) {
return true;
}
#Override
protected Object getValue(Object element) {
// TODO Auto-generated method stub
return 0;
}
#Override
protected void setValue(Object element, Object value) {
/* only set new value if it differs from old one */
}
}
***************************************************
When i click on the cell of column2 i get the combo box but when i select something and move the focus somewhere else.It again shows the default Value
on debuging i found that :
it agains calls the label Provider which fetches all the Version of the package and then shows the first one hence I can not see any change.
what i want is that it should keep the selection intact without changing the underlying object.
thanks for the help.

Figured it out.
following code added to the SetValue() method solves it.
m_tree = (Tree)getViewer.getControl();
TreeItem[] ti = m_tree.getSelection();
CCombo c = ((CCombo)cellEditor.getControl());
String str = c.getItem(c.getSelectionIndex());
ti[0].setText(1, str );

How to add a function in jTable that sorts the column?

I know that by using JTable the column is sorted when we click on the column heading, but what I want is that, when I right-click on the column name a function name 'sort' should be displayed. Any suggestion in doing it?

Start by adding a MouseListener to the table. See How to write mouse listeners
You will need to translate the click point to a column, see JTable#columnAtPoint.
You will then need to update the SortKey for the table. Check out Sorting and Filtering for an example

If I understand you correctly, you want to sort by some explicit action (triggered f.i. in a popup) instead of by the normal left-click.
If so, the tricky part is to force the ui-delegate to do nothing. There are two options:
hook into the default mouse listener installed by the ui delegate, as described in a recent QA
let the ui do its stuff, but fool it by a sorter implementation that doesn't follow the rules (beware: that's as dirty as the first approach!)
The mis-behaving sorter:
public class MyTableRowSorter extends TableRowSorter {
public MyTableRowSorter(TableModel model) {
super(model);
}
/**
* Implemented to do nothing to fool tableHeader internals.
*/
#Override
public void toggleSortOrder(int column) {
}
/**
* The method that really toggles, called from custom code.
*
* #param column
*/
public void realToggleSortOrder(int column) {
super.toggleSortOrder(column);
}
}
// usage
final JTable table = new JXTable(new AncientSwingTeam());
table.setRowSorter(new MyTableRowSorter(table.getModel()));
Action toggle = new AbstractAction("toggleSort") {
#Override
public void actionPerformed(ActionEvent e) {
JXTableHeader header = SwingXUtilities.getAncestor(
JXTableHeader.class, (Component) e.getSource());
Point trigger = header.getPopupTriggerLocation();
int column = trigger != null ? header.columnAtPoint(trigger) : -1;
if (column < 0) return;
int modelColumn = header.getTable().convertColumnIndexToModel(column);
((MyTableRowSorter) header.getTable().getRowSorter())
.realToggleSortOrder(modelColumn);
}
};
JPopupMenu menu = new JPopupMenu();
menu.add(toggle);
table.getTableHeader().setComponentPopupMenu(menu);
Yeah, couldn't resist throwing in some SwingX api, lazy me :-) With plain Swing, you'll have to write some lines more but the basics are the same: install the tricksy sorter and use its custom toggle sort to really sort whereever needed, f.i. in a mouseListener.

Is it possible to set an action to a JComponent without reseting its properties?

I've read the Java trail oracle provides and they said that the objects properties are set to match the actions properties. I would like to know if this is a limited set of properties that is shared, or if the Action is casted to the same class as the object you are setting the action to.
Another question I have is such... is it possible to set the Action to have the same properties as the Component that I'm setting it to so that it doesn't reset everything? The only work around that I can think of is either setting the action for the object before doing anything with the object, or passing the object through the actions methods or constructor and setting all the values you want at that point. I was hoping however I could set the actions at a later time in the program without disturbing anything, it be more convenient.
Example ...
JMenuItem myItem = new JMenuItem("someText");
myItem.setAction(myAction);// Clears the text from my menu item which is the problem
Thanks

Me:
Why not have "someText" associated with the Action from the get-go?
You:
How do I do that?
Solution:
// can also pass in an icon to this constructor as a 2nd parameter
Action myAction = new AbstractAction("Some Text") {
{
// set properties here including mnemmonic
putValue(MNEMONIC_KEY, KeyEvent.VK_S);
}
#Override
public void actionPerformed(ActionEvent e) {
// action initiated code goes here
}
};
Also you can set the button's text via the Action's NAME property:
Action myAction = new AbstractAction() {
{
putValue(NAME, "Some Text");
putValue(MNEMONIC_KEY, KeyEvent.VK_S);
}
// ... etc...
};

Change focus to next component in JTable using TAB

JTable's default behavior is changing focus to next cell and I want to force it to move focus to next component (e.g. JTextField) on TAB key pressed.
I overrided isCellEditable method of DefaultTableModel to always return false:
public boolean isCellEditable(int rowIndex, int columnIndex) {
return false;
}
But it still doesn't change focus to next component!
How should I make JTable change focus to next component instead of next cell?

The shift-/tab keys are used by default for transfering focus between components. JTable explicitly requests to handle the shift-/tab internally (by providing sets of focusTraversalKeys which doesn't include those).
Following the general rule (if there's specilized api available for a task, use that instead of rolling your own), the solution is to set traversal keys to again contain them:
Set<AWTKeyStroke> forward = new HashSet<AWTKeyStroke>(
table.getFocusTraversalKeys(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS));
forward.add(KeyStroke.getKeyStroke("TAB"));
table.setFocusTraversalKeys(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, forward);
Set<AWTKeyStroke> backward = new HashSet<AWTKeyStroke>(
table.getFocusTraversalKeys(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS));
backward.add(KeyStroke.getKeyStroke("shift TAB"));
table.setFocusTraversalKeys(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, backward);

If you really want this, you need to change the default behavior of the tables action map.
ActionMap am = table.getActionMap();
am.put("selectPreviousColumnCell", new PreviousFocusHandler());
am.put("selectNextColumnCell", new NextFocusHandler());
Then you need a couple of actions to handle the traversal
public class PreviousFocusHandler extends AbstractAction {
public void actionPerformed(ActionEvent evt) {
KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
manager.focusPreviousComponent();
}
}
public class NextFocusHandler extends AbstractAction {
public void actionPerformed(ActionEvent evt) {
KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
manager.focusNextComponent();
}
}
Another approach would be to disable the underlying Action...
ActionMap am = table.getActionMap();
am.get("selectPreviousColumnCell").setEnabled(false);
am.get("selectNextColumnCell").setEnabled(false);
(haven't tested this)
The benefit of this approach is can enable/disable the behaviour as you need it without needing to maintain a reference to the old Actions

default (implemented KeyBinding for JTable) is about next cell and from last cell to first,
you can to remove KeyBindings by setting to the null value

To reset to the standard keyboard bindings (typically TAB and SHIFT+TAB), simply specify null for the keystrokes parameter to Component.setFocusTraversalKeys:
table.setFocusTraversalKeys(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, null);
table.setFocusTraversalKeys(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, null);

JTable: single selection for the user, multiple selections programmatically

I have a JTable where the user should be able to select only a single row, but whenever a row is selected by the user, some other rows (that are related according to some logic) should also be selected programmatically. The problem is that if I set the selection mode of the table to ListSelectionModel.SINGLE_SELECTION, addRowSelectionInterval will also select only one row. Any ideas?
EDIT: I think all ideas (custom selection model, clearing all but last user selections, custom renderer for highlighting) were good, but the best is to use SwingX, because it doesn't require much infrastructure-code, only a clever usage of the library. (and it's easy to be clever when a SwingX-guru is helping :)

Biased me would say: certainly much easier in SwingX :-)
All you need is
a custom HighlightPredicate which decides about what is related
a ColorHighlighter configured with the selectionColors
set the custom predicate on receiving change notification from the selection model
Some code:
// the custom predicate
public static class RelatedHighlightPredicate implements HighlightPredicate {
List<Integer> related;
public RelatedHighlightPredicate(Integer... related) {
this.related = Arrays.asList(related);
}
#Override
public boolean isHighlighted(Component renderer,
ComponentAdapter adapter) {
int modelIndex = adapter.convertRowIndexToModel(adapter.row);
return related.contains(modelIndex);
}
}
// its usage
JXTable table = new JXTable(someModel);
table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
final ColorHighlighter hl = new ColorHighlighter(HighlightPredicate.NEVER,
table.getSelectionBackground(), table.getSelectionForeground());
table.addHighlighter(hl);
ListSelectionListener l = new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
if (e.getValueIsAdjusting()) return;
invokeUpdate((ListSelectionModel) e.getSource());
}
private void invokeUpdate(final ListSelectionModel source) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
int singleSelection = source.getMinSelectionIndex();
if (singleSelection >= 0) {
int first = Math.max(0, singleSelection - 2);
int last = singleSelection + 2;
hl.setHighlightPredicate(new RelatedHighlightPredicate(first, last));
} else {
hl.setHighlightPredicate(HighlightPredicate.NEVER);
}
}
});
}
};
table.getSelectionModel().addListSelectionListener(l);

You might set multiselection possible for the table, but with each selection change - take only 1 (last selected) row, clear other selections and add your own computed selection.

The problem is that if I set the selection mode of the table
use ListSelectionModel.SINGLE_SELECTION for events came from mouse and keyborad
some other rows (that are related according to some logic) should also be selected programmatically
have look at Renderer for JTable, then required row(s), columns or whatever could be highlighted until programmatic rules stay unchanged
... maybe will help you