org.eclipse.nebula.widgets.nattable.core/src/org/eclipse/nebula/widgets/nattable/ui/action/DragModeEventHandler.java

/*******************************************************************************
 * Copyright (c) 2012, 2014 Original authors and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Original authors and others - initial API and implementation
 *     Dirk Fauth <dirk.fauth@googlemail.com> - Bug 453882
 ******************************************************************************/
package org.eclipse.nebula.widgets.nattable.ui.action;

import org.eclipse.nebula.widgets.nattable.NatTable;
import org.eclipse.nebula.widgets.nattable.ui.mode.AbstractModeEventHandler;
import org.eclipse.nebula.widgets.nattable.ui.mode.Mode;
import org.eclipse.nebula.widgets.nattable.ui.mode.ModeSupport;
import org.eclipse.nebula.widgets.nattable.ui.mode.MouseModeEventHandler;
import org.eclipse.nebula.widgets.nattable.ui.util.MouseEventHelper;
import org.eclipse.swt.events.FocusEvent;
import org.eclipse.swt.events.MouseEvent;

public class DragModeEventHandler extends AbstractModeEventHandler {

    private final IDragMode dragMode;

    private final MouseModeEventHandler parentModeEventHandler;
    private final MouseEvent mouseDownEvent;

    private boolean realDrag = false;

    public DragModeEventHandler(
            ModeSupport modeSupport,
            NatTable natTable,
            IDragMode dragMode,
            MouseModeEventHandler parentModeEventHandler,
            MouseEvent mouseDownEvent) {

        super(modeSupport, natTable);

        this.dragMode = dragMode;
        this.parentModeEventHandler = parentModeEventHandler;
        this.mouseDownEvent = mouseDownEvent;
    }

    @Override
    public void mouseMove(MouseEvent event) {
        this.dragMode.mouseMove(this.natTable, event);

        if (!this.realDrag
                && !MouseEventHelper.treatAsClick(this.mouseDownEvent, event)) {
            this.realDrag = true;
        }
    }

    @Override
    public void mouseUp(MouseEvent event) {
        this.dragMode.mouseUp(this.natTable, event);
        switchMode(Mode.NORMAL_MODE);

        // Bug 379884
        // check if the drag operation started and ended within the same cell
        // in that case the registered click operation is executed also
        if (!this.realDrag
                && MouseEventHelper.eventOnSameCell(this.natTable, this.mouseDownEvent, event)) {
            this.parentModeEventHandler.mouseUp(event);
        }
    }

    @Override
    public void focusLost(FocusEvent event) {
        // Bug 453882
        // NatTable lost the focus while a drag operation was active
        // so we simple skip the drag operation by calling mouseUp using the
        // initial mouseDown event
        mouseUp(this.mouseDownEvent);
    }
}