SWT Table inside ScrolledCompsite: no scrolling by Mouse Wheel - swt

Question

The code below is taken from:
How to always show vertical scroll bar in SWT table?
Table in the ScrolledComposite scrolls only by moving vertical scrollbar by Mouse or by putting Mouse directly onto vertical scrollbar and scroll the Wheel.
Could you advise, please, how to make table scrollable by Mouse Wheel by putting Mouse onto the Table?
public static void main(String[] args)
{
final Display display = new Display();
final Shell shell = new Shell(display);
shell.setLayout(new GridLayout());
final ScrolledComposite composite = new ScrolledComposite(shell, SWT.V_SCROLL);
composite.setLayout(new GridLayout());
composite.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
final Table table = new Table(composite, SWT.NO_SCROLL | SWT.FULL_SELECTION);
table.setHeaderVisible(true);
composite.setContent(table);
composite.setExpandHorizontal(true);
composite.setExpandVertical(true);
composite.setAlwaysShowScrollBars(true);
composite.setMinSize(table.computeSize(SWT.DEFAULT, SWT.DEFAULT));
Button fillTable = new Button(shell, SWT.PUSH);
fillTable.setText("Fill table");
fillTable.setLayoutData(new GridData(SWT.FILL, SWT.END, true, false));
fillTable.addListener(SWT.Selection, new Listener()
{
#Override
public void handleEvent(Event arg0)
{
if (table.getColumnCount() < 1)
{
for (int col = 0; col < 4; col++)
{
TableColumn column = new TableColumn(table, SWT.NONE);
column.setText("Column " + col);
}
}
for (int row = 0; row < 20; row++)
{
TableItem item = new TableItem(table, SWT.NONE);
for (int col = 0; col < table.getColumnCount(); col++)
{
item.setText(col, "Item " + row + " " + col);
}
}
for (int col = 0; col < table.getColumnCount(); col++)
{
table.getColumn(col).pack();
}
composite.setMinSize(table.computeSize(SWT.DEFAULT, SWT.DEFAULT));
}
});
Button clearTable = new Button(shell, SWT.PUSH);
clearTable.setText("Clear table");
clearTable.setLayoutData(new GridData(SWT.FILL, SWT.END, true, false));
clearTable.addListener(SWT.Selection, new Listener()
{
#Override
public void handleEvent(Event arg0)
{
table.removeAll();
composite.setMinSize(table.computeSize(SWT.DEFAULT, SWT.DEFAULT));
}
});
shell.pack();
shell.setSize(400, 300);
shell.open();
while (!shell.isDisposed())
{
if (!display.readAndDispatch())
display.sleep();
}
display.dispose();
}

Answer 1

The table is receiving the mouse wheel events which it is ignoring because the Table control is large enough to show all the rows.
I don't see a way to just pass on the wheel events to the scrolled composite.
You could try listening to the wheel events in the table and adjusting the scrolled composite origin - something like:
table.addListener(SWT.MouseVerticalWheel, event ->
{
Point origin = scrolled.getOrigin();
origin.y -= event.count;
scrolled.setOrigin(origin);
});
The count field in the wheel event is 1/-1 depending on the scrolling direction.