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How to trigger EditingSupport on TableViewer

I'm currently writing an application where I use a JFace TableViewer. There's a Button next to the table that adds a new item to it. The TableViewer has only one column in this example, but this column has an EditingSupport assigned to it.
That all works as expected. A new item is added to the table when I click the button and it's also selected automatically.
However, what I want to achieve is that the EditingSupport of this column is triggered for the new item, i.e. when a new item is added, the cell within the new row should automatically show the text input that shows up when you use the editing support.
How would I achieve that? Do I need to fake up a mouse event or is there something in the API that I'm missing?
Here's some example code that roughly shows the current state of the table
public static void main(String[] args)
{
final Display d = new Display();
Shell s = new Shell(d);
s.setLayout(new FillLayout());
List<Project> projects = new ArrayList<>();
Table table = new Table(s, SWT.SINGLE | SWT.H_SCROLL | SWT.V_SCROLL | SWT.FULL_SELECTION | SWT.BORDER);
table.setHeaderVisible(true);
TableViewer viewer = new TableViewer(table);
viewer.setContentProvider(ArrayContentProvider.getInstance());
viewer.setInput(projects);
TableViewerColumn nameColumn = new TableViewerColumn(viewer, SWT.NONE);
nameColumn.getColumn().setText("Project name");
nameColumn.setLabelProvider(new ColumnLabelProvider()
{
#Override
public String getText(Object element)
{
Project p = (Project) element;
return p.name;
}
});
// Add the editing support
nameColumn.setEditingSupport(new ProjectNameEditingSupport(viewer));
// Button to add new item
Button add = new Button(s, SWT.PUSH);
add.setText("Add");
add.addListener(SWT.Selection, e -> {
// Create the new item
Project project = new Project("Project");
projects.add(project);
// Refresh the table
viewer.refresh();
// Select the item
viewer.setSelection(new StructuredSelection(project), true);
// TODO: Trigger editing support
});
for (TableColumn c : viewer.getTable().getColumns())
c.pack();
s.pack();
s.open();
s.setSize(300, 400);
while (!s.isDisposed())
{
if (!d.readAndDispatch())
d.sleep();
}
d.dispose();
}
private static class Project
{
private String name;
public Project(String name)
{
this.name = name;
}
}
public static class ProjectNameEditingSupport extends EditingSupport
{
private final TableViewer viewer;
private final CellEditor editor;
public ProjectNameEditingSupport(TableViewer viewer)
{
super(viewer);
this.viewer = viewer;
this.editor = new TextCellEditor(viewer.getTable());
}
#Override
protected CellEditor getCellEditor(Object element)
{
return editor;
}
#Override
protected boolean canEdit(Object element)
{
return true;
}
#Override
protected Object getValue(Object element)
{
return ((Project) element).name;
}
#Override
protected void setValue(Object element, Object userInputValue)
{
((Project) element).name = String.valueOf(userInputValue);
viewer.update(element, null);
}
}

IIRC you can use ColumnViewer::editElement in order to activate the editing control. The first method argument is the element that should be edited, the second argument is the index of the column on which the editor should be opened.
For example:
viewer.editElement( project, 0 );

JFace TreeViewer expand or collapse on selection

I've implemented a selection listener for my treeviewer to expand or collapse a node on selection.
This impementation works fine for collapsing, but does not expand a node.
this.getTree().addListener(SWT.Selection, new Listener() {
#Override
public void handleEvent(Event event) {
TreeItem treeItem = (TreeItem) event.item;
if (treeItem.getItems().length > 0) {
if (MyTreeViewer.this.getExpandedState(treeItem)) {
MyTreeViewer.this.collapseToLevel(treeItem, MyTreeViewer.this.ALL_LEVELS);
} else {
MyTreeViewer.this.expandToLevel(treeItem, 1);
}
MyTreeViewer.this.refresh();
}
}
});
Do you have any suggestions how to fix this?

For a JFace TreeViewer you should use a ISelectionChangedListener or a IDoubleClickListener - do not use the underlying Tree listeners as they may not interact correctly with the viewer.
This is what I use for double click:
public class TreeDoubleClickListener implements IDoubleClickListener
{
#Override
public void doubleClick(final DoubleClickEvent event)
{
IStructuredSelection selection = (IStructuredSelection)event.getSelection();
if (selection == null || selection.isEmpty())
return;
Object sel = selection.getFirstElement();
TreeViewer treeViewer = (TreeViewer)event.getViewer();
IContentProvider provider = treeViewer.getContentProvider();
if (provider instanceof ITreeContentProvider)
{
ITreeContentProvider treeProvider = (ITreeContentProvider)provider;
if (!treeProvider.hasChildren(sel))
return;
if (treeViewer.getExpandedState(sel))
treeViewer.collapseToLevel(sel, AbstractTreeViewer.ALL_LEVELS);
else
treeViewer.expandToLevel(sel, 1);
}
}
}
The key thing here is to use the selection as the argument to collapseToLevel / expandToLevel.
Just change to implement ISelectionChangedListener to work on selection.
Add the listener with TreeViewer addDoubleClickListener or addSelectionChangedListener

TreeTableView TableMenuButton setonAction

Is there any possible way to listen or to override the default TableMenuButton setonAction?
Something like this?
TreeTableView ttv = new TreeTableView();
ttv.setTableMenuButtonVisible(true);
ttv.setOnMouseClicked((MouseEvent event) -> {
....
});
I would like to know which column has been set to visible or invisible.
Any help is greatly appreciated.

I created an example about how to adapt the TableView's menu button. The TreeTableView is just similar. What you need to do is to get the ContextMenu. You can get it either by reflection or by using a lookup. Once you have it, you can do whatever you want with it.
I also filed a change request so that the context menu becomes accessible since the current implementation isn't satisfactory.
Here's the modified code of the lookup version:
public class TableUtils {
/**
* Make table menu button visible and replace the context menu with a custom context menu via reflection.
* The preferred height is modified so that an empty header row remains visible. This is needed in case you remove all columns, so that the menu button won't disappear with the row header.
* IMPORTANT: Modification is only possible AFTER the table has been made visible, otherwise you'd get a NullPointerException
* #param tableView
*/
public static void addCustomTableMenu( TreeTableView tableView) {
// enable table menu
tableView.setTableMenuButtonVisible(true);
// replace internal mouse listener with custom listener
setCustomContextMenu( tableView);
}
private static void setCustomContextMenu( TreeTableView table) {
TreeTableViewSkin<?> tableSkin = (TreeTableViewSkin<?>) table.getSkin();
// get all children of the skin
ObservableList<Node> children = tableSkin.getChildren();
// find the TableHeaderRow child
for (int i = 0; i < children.size(); i++) {
Node node = children.get(i);
if (node instanceof TableHeaderRow) {
TableHeaderRow tableHeaderRow = (TableHeaderRow) node;
// setting the preferred height for the table header row
// if the preferred height isn't set, then the table header would disappear if there are no visible columns
// and with it the table menu button
// by setting the preferred height the header will always be visible
// note: this may need adjustments in case you have different heights in columns (eg when you use grouping)
double defaultHeight = tableHeaderRow.getHeight();
tableHeaderRow.setPrefHeight(defaultHeight);
for( Node child: tableHeaderRow.getChildren()) {
// child identified as cornerRegion in TableHeaderRow.java
if( child.getStyleClass().contains( "show-hide-columns-button")) {
// get the context menu
ContextMenu columnPopupMenu = createContextMenu( table);
// replace mouse listener
child.setOnMousePressed(me -> {
// show a popupMenu which lists all columns
columnPopupMenu.show(child, Side.BOTTOM, 0, 0);
me.consume();
});
}
}
}
}
}
/**
* Create a menu with custom items. The important thing is that the menu remains open while you click on the menu items.
* #param cm
* #param table
*/
private static ContextMenu createContextMenu( TreeTableView table) {
ContextMenu cm = new ContextMenu();
// create new context menu
CustomMenuItem cmi;
// select all item
Label showAll = new Label("Show all");
showAll.addEventHandler(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
for (Object obj : table.getColumns()) {
((TreeTableColumn<?, ?>) obj).setVisible(true);
}
}
});
cmi = new CustomMenuItem(showAll);
cmi.setHideOnClick(false);
cm.getItems().add(cmi);
// deselect all item
Label hideAll = new Label("Hide all");
hideAll.addEventHandler(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
for (Object obj : table.getColumns()) {
((TreeTableColumn<?, ?>) obj).setVisible(false);
}
}
});
cmi = new CustomMenuItem(hideAll);
cmi.setHideOnClick(false);
cm.getItems().add(cmi);
// separator
cm.getItems().add(new SeparatorMenuItem());
// menu item for each of the available columns
for (Object obj : table.getColumns()) {
TreeTableColumn<?, ?> tableColumn = (TreeTableColumn<?, ?>) obj;
CheckBox cb = new CheckBox(tableColumn.getText());
cb.selectedProperty().bindBidirectional(tableColumn.visibleProperty());
cmi = new CustomMenuItem(cb);
cmi.setHideOnClick(false);
cm.getItems().add(cmi);
}
return cm;
}
}

JavaFX CheckBoxTreeItem Selection

I have a javafx checkbox tree. I need to select the checkbox when the tree item is clicked. I have added a listener for the selection property of the tree view. But the listener gets fired only when the tree item is clicked. The above listener is not fired when the checkbox is clicked.
Required: A listener that fires when a tree item or checkbox is clicked in the treeview.
Code:
String memberArray = {"subChild1", "subChild2", "childSub1"}
Group groupRoot = new Group();
Scene scene = new Scene(groupRoot, Color.ALICEBLUE);
HBox hBox = new HBox();
hBox.setMaxWidth(fxPanel.getWidth());
final Label royalLabel = new Label("Select a item");
TreeSet<String> prefixMember = new TreeSet<String>();
String tmpName = null;
LinkedHashSet<CheckBoxTreeItem<String>> treeItems = new LinkedHashSet<CheckBoxTreeItem<String>>();
LinkedHashSet<CheckBoxTreeItem<String>> treeSubItems = new LinkedHashSet<CheckBoxTreeItem<String>>();
for (String item : memberArray) {
if (!item.isEmpty()) {
tmpName = item.substring(0, 3);
prefixMember.add(tmpName);
}
}
// Create and empty TreeView
TreeView<String> duckTree = new TreeView<String>();
// Create TreeItems for the Hierarchy of the TreeView
CheckBoxTreeItem<String> root = new CheckBoxTreeItem<String>("Parent");
CheckBoxTreeItem<String> lm1 = new CheckBoxTreeItem<String>("Child1");
CheckBoxTreeItem<String> lm2 = new CheckBoxTreeItem<String>("Child2");
for (String item : prefixMember) {
CheckBoxTreeItem<String> treeItem = new CheckBoxTreeItem<String>(item.toString());
for (String subItem : memberArray) {
if (!subItem.isEmpty() && subItem.substring(0, 3).equals(item)) {
CheckBoxTreeItem<String> treeSubItem = new CheckBoxTreeItem<String>(
subItem.toString());
treeSubItems.add(treeSubItem);
}
}
treeItems.add(treeItem);
treeItem.getChildren().addAll(treeSubItems);
treeSubItems.clear();
}
root.getChildren().addAll(treeItems);
treeItems.clear();
// Create a TreeView using the root TreeItem
TreeView<String> royalTree = new TreeView<String>(root);
royalTree.setCellFactory(CheckBoxTreeCell.<String>forTreeView());
// Set a ChangeListener to handle events that occur with a Treeitem
// is selected
royalTree.getSelectionModel().selectedItemProperty()
.addListener(new ChangeListener<TreeItem<String>>() {
public void changed(
ObservableValue<? extends TreeItem<String>> observableValue,
TreeItem<String> oldItem, TreeItem<String> newItem) {
// Gets fired only on selection of tree item
// Need to get fired on selection of check box too
// Select the respective checkbox on selection of tree item
}
});
hBox.getChildren().add(royalTree);
groupRoot.getChildren().add(hBox);
fxPanel.setScene(scene);

You could just add an EventHandler to your root item in the tree:
rootItem.addEventHandler(CheckBoxTreeItem.checkBoxSelectionChangedEvent(), new EventHandler<TreeModificationEvent<Object>>() {
#Override
public void handle(TreeModificationEvent<Object> event) {
// Your code here.
}
});

i had the same problem and searched looong time. Sadly there is not offical documentation for this from oracle.
The answer is to set the CellFactory and call the getSelectedStateCallback().call(this.getTreeItem());
for your treeItem in the updateItem:
// set cellFactory
royalTree.setCellFactory(new Callback<TreeView<String>, TreeCell<String>>() {
#Override
public TreeCell<String> call(TreeView<String> p) {
// return new CheckBoxTreeCell, you also can make a new class with this
return new CheckBoxTreeCell<String>() {
#Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (!empty) {
// call the selectedStat Callback for treeitem
ObservableValue<Boolean> selectedState = getSelectedStateCallback().call(this.getTreeItem());
if (selectedState != null) {
// do something here
}
}
}
};
}
});
i have tested this in fx 8, but it should also work in fx 2.2
happy coding,
kalasch

Yes, adding an event handler to the tree item works. Here is some example code (Java 8) with a TreeView with items as CheckBoxTreeItem:
CheckBoxTreeItem<Path> rootItem = new CheckBoxTreeItem<>(rootDirPath);
rootItem.addEventHandler(
CheckBoxTreeItem.<Path>checkBoxSelectionChangedEvent(),
(TreeModificationEvent<Path> e) -> {
CheckBoxTreeItem<Path> item = e.getTreeItem();
if (item.isSelected() || item.isIndeterminate()) {
System.out.println("Some items are checked");
}
else {
System.out.println("Some items are unchecked");
}
});
TreeView<Path> tree = new TreeView<>(rootItem);
tree.getSelectionModel().setSelectionMode(SelectionMode.MULTIPLE);

Do you require an event for each selection immediately? If not you can create an arraylist of all your checkboxtreeitems and iterate through that to check for selected or not selected when you need it.

Showing a right click menu for a SWT TableItem?

Is it possible to show a right click menu on table items with SWT? The menu would be different for every item, e.g for some rows, some of the menu items would be enabled, for others, they would be disabled. So, each row would need its own menu, and when setting up the menu i'd need a way to identify which row I was working with.
Any ideas?

Listening for SWT.MouseDown, as suggested by #user4793956, is completely useless. The context menu is always brought up, no need to call setVisible(true). Quite contrary, you need to cancel the SWT.MenuDetect event, if you do not want the menu to pop up.
This works for me:
// Create context menu
Menu menuTable = new Menu(table);
table.setMenu(menuTable);
// Create menu item
MenuItem miTest = new MenuItem(menuTable, SWT.NONE);
miTest.setText("Test Item");
// Do not show menu, when no item is selected
table.addListener(SWT.MenuDetect, new Listener() {
#Override
public void handleEvent(Event event) {
if (table.getSelectionCount() <= 0) {
event.doit = false;
}
}
});

Without using a DynamicTable:
Menu contextMenu = new Menu(table);
table.setMenu(contextMenu);
MenuItem mItem1 = new MenuItem(contextMenu, SWT.None);
mItem1.setText("Menu Item Test.");
table.addListener(SWT.MouseDown, new Listener(){
#Override
public void handleEvent(Event event) {
TableItem[] selection = table.getSelection();
if(selection.length!=0 && (event.button == 3)){
contextMenu.setVisible(true);
}
}
});

table = new DynamicTable(shell, SWT.BORDER | SWT.FULL_SELECTION);
table.addMenuDetectListener(new MenuDetectListener()
{
#Override
public void menuDetected(MenuDetectEvent e)
{
int index = table.getSelectionIndex();
if (index == -1)
return; //no row selected
TableItem item = table.getItem(index);
item.getData(); //use this to identify which row was clicked.
//The popup can now be displayed as usual using table.toDisplay(e.x, e.y)
}
});
More details: http://www.eclipsezone.com/eclipse/forums/t49734.html