package bndtools.release.ui;
import java.util.Arrays;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerComparator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
public class TableSortingEnabler {
public static void applyTableColumnSorting(TableViewer tableViewer) {
TableSortingEnabler enabler = new TableSortingEnabler();
enabler.setTableViewer(tableViewer);
}
private TableViewer tableViewer;
private TableSortingEnabler() {
}
private void setTableViewer(TableViewer tableViewer) {
this.tableViewer = tableViewer;
addColumnSelectionListeners(tableViewer);
tableViewer.setComparator(new ViewerComparator() {
@Override
public int compare(Viewer viewer, Object e1, Object e2) {
return compareElements(e1, e2);
}
});
}
private void addColumnSelectionListeners(TableViewer tableViewer) {
TableColumn[] columns = tableViewer.getTable().getColumns();
for (int i = 0; i < columns.length; i++) {
addColumnSelectionListener(columns[i]);
}
}
private void addColumnSelectionListener(TableColumn column) {
column.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent e) {
tableColumnClicked((TableColumn) e.widget);
}
});
}
private void tableColumnClicked(TableColumn column) {
Table table = column.getParent();
if (column.equals(table.getSortColumn())) {
int direction = getSortDirection(table.getSortDirection());
table.setSortDirection(direction);
if (direction == SWT.NONE) {
table.setSortColumn(null);
}
} else {
table.setSortColumn(column);
table.setSortDirection(getSortDirection(SWT.NONE));
}
tableViewer.refresh();
}
private static int getSortDirection(int currentDirection) {
switch (currentDirection) {
case SWT.NONE:
return SWT.UP;
case SWT.UP:
return SWT.DOWN;
default:
return SWT.NONE;
}
}
@SuppressWarnings({
"rawtypes", "unchecked"
})
private int compareElements(Object e1, Object e2) {
IColumnContentProvider columnValueProvider = (IColumnContentProvider) tableViewer.getContentProvider();
Table table = tableViewer.getTable();
int index = Arrays.asList(table.getColumns()).indexOf(table.getSortColumn());
int result = 0;
if (index != -1) {
Comparable c1 = columnValueProvider.getValue(e1, index);
Comparable c2 = columnValueProvider.getValue(e2, index);
result = c1.compareTo(c2);
}
return table.getSortDirection() == SWT.UP ? result : -result;
}
public interface IColumnContentProvider {
Comparable<?> getValue(Object element, int column);
}
}