I.T. aware

The Eclipse Nebula sub-project present the Grid widget, an alpha version which works great, i use it in my application to administrate reservation of swimming course. The JFace layer is not implemented yet but it’s on rails. But I don’t know if a GridViewer will be very useful because the needs of a spreadsheet are very large.

This is an example of Grid with header of columns and rows, column grouping, expand/collapse event of group column. The objective is to show the schedules in columns and the week days in rows, each column is composed of 3 sub-columns showing the total capacity, the availability and the sold place. The total capacity column can be desactivated :

public Grid createGrid(List in_schedules, Composite in_composite) {
        // Grid creation
        Grid l_grid = new Grid(in_composite, SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL);
        // show column header
        l_grid.setHeaderVisible(true);
        // show row header
        l_grid.setRowHeaderVisible(true);
        // enable cell selection
        l_grid.setCellSelectionEnabled(true);
        GC l_gc = new GC(l_grid);
        // list of swimming course schedules
        for (ScheduleType l_scheduleType : in_schedules) {
            // create column group with dynamic column (TOGGLE)
            GridColumnGroup l_scheduleColumn = new GridColumnGroup(l_grid, SWT.TOGGLE);
            // column group header name
            l_scheduleColumn.setText(l_scheduleType.getLabel());
            final int l_colWidth = l_gc.stringExtent(l_scheduleType.getLabel() + " <<").x + 6;
            // initialize state (collapse)
            l_scheduleColumn.setExpanded(false);
            // listen expand event
            l_scheduleColumn.addListener(SWT.Expand, new Listener() {
                public void handleEvent(Event event) {
                    int l_width = l_colWidth / 3;
                    if (l_width < 20) {
                        l_width = 20;
                    }
                    for (GridColumn l_column : ((GridColumnGroup) event.widget).getColumns()) {
                        l_column.setWidth(l_width);
                    }
                }
            });
            // listen collapse event
            l_scheduleColumn.addListener(SWT.Collapse, new Listener() {
                public void handleEvent(Event event) {
                    int l_width = l_colWidth / 2;
                    if (l_width < 20) {
                        l_width = 20;
                    }
                    for (GridColumn l_column : ((GridColumnGroup) event.widget).getColumns()) {
                        if (l_column.isSummary()) {
                            l_column.setWidth(l_width);
                        }
                    }
                }
            });
            int l_width = l_colWidth / 2;
            if (l_width < 20) {
                l_width = 20;
            }
            // create columns group
            GridColumn l_capacity = new GridColumn(l_scheduleColumn, SWT.CENTER);
            l_capacity.setText("C");
            l_capacity.setWidth(20);
            l_capacity.setCellSelectionEnabled(false);
            // collapsed ? no
            l_capacity.setSummary(false);
            l_capacity = new GridColumn(l_scheduleColumn, SWT.CENTER);
            l_capacity.setText("V");
            l_capacity.setWidth(l_width);
            l_capacity.setCellSelectionEnabled(false);
            // collapsed ? yes
            l_capacity.setSummary(true);
            l_capacity = new GridColumn(l_scheduleColumn, SWT.CENTER);
            l_capacity.setText("L");
            l_capacity.setWidth(l_width);
            l_capacity.setSummary(true);
            l_capacity.setData(l_scheduleType);
        }
        l_gc.dispose();
        //l_grid.pack(true);
        return l_grid;
    }

The Grid binding is realise via the GridItem object

// GridItem creation
l_gridItem = new GridItem(l_grid, SWT.CENTER);
// row header name
l_gridItem.setHeaderText(l_headerText);
// set value by index column
l_gridItem.setText(, );

It possible to merge cell of a same line e.g.:
e.g.:

l_gridItem.setColumnSpan(0, in_grid.getColumnCount());

And to get the selection :

Point[] l_selections = l_grid.getCellSelection();
for (Point l_selection : l_selections) {
	// get GridItem
	l_grid.getItem(l_selection.y);
	// get GridColumn
	l_grid.getColumn(l_selection.x)
}