Question

Is it possible to have a button in a TableViewerColumn? There are several posts that confirm this, but I’ve found no code that actually works. I’ve read about a DialogCellEditor, too, is that what to look into?

Regards,
Marcus

Answer 1

As this seems to be a common problem, I’ve tried a workaround. I use an image as label and add editing support like so:

        col = createTableViewerColumn(titles[10], bounds[10], 10);
    col.setEditingSupport(new DeleteSupport(viewer));
    col.setLabelProvider(new ColumnLabelProvider() {
        @Override
        public Image getImage(Object element) {
            return new Image(ApplicationRunner.getApp().getShell()
                    .getDisplay(), "ressources/images/delete.png");
        }

        @Override
        public String getText(Object element) {
            return "";
        }
    });

In the DeleteSupport class (extending EditingSupport), you have to let canEdit() return false, so the image is not selectable. But then, you can’t work with getValue(). So, I do whatever I have to in canEdit() BEFORE returning false. That’s the same behavior as a simple push button would have.

The DeleteSupport looks like this:

public class DeleteSupport extends EditingSupport {

private final TableViewer viewer;

public DeleteSupport(TableViewer viewer) {
    super(viewer);
    this.viewer = viewer;
}

@Override
protected CellEditor getCellEditor(Object element) {
    return new TextCellEditor(viewer.getTable());
}

@Override
protected boolean canEdit(Object element) {

            // if confirmed, try to delete the customer
    if (MessageDialog.openConfirm(  ApplicationRunner.getApp().getShell(),
                    "Confirm delete",
                    "Soll " + ((Customer) element).getFirstname()
                    + " " + ((Customer) element).getLastname()
                    + " be deleted? Cannot be undone!")) {

        try {
            CustomerDAO.getInstance().delete(((Customer) element).getId());
        } catch (SQLException e) {
            // TODO something
        }
    }

            // reload anyways
    try {
        viewer.setInput(CustomerDAO.getInstance().getAll());
    } catch (SQLException e) {
        // TODO something else
    }
    viewer.refresh();

    return false;
}

@Override
protected Object getValue(Object element) {
    return "";
}

@Override
protected void setValue(Object element, Object value) {
}

}