com.github.jknack.antlr4ide.ui.railroad.RailroadView.java Source code

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Here is the source code for com.github.jknack.antlr4ide.ui.railroad.RailroadView.java

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/*******************************************************************************
 * Copyright (c) 2010 itemis AG (http://www.itemis.eu)
 * 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:
 *   Jan Koehnlein - Initial API and implementation
 *******************************************************************************/
package com.github.jknack.antlr4ide.ui.railroad;

import java.util.List;

import org.eclipse.draw2d.Figure;
import org.eclipse.draw2d.FigureCanvas;
import org.eclipse.draw2d.IFigure;
import org.eclipse.draw2d.StackLayout;
import org.eclipse.draw2d.Viewport;
import org.eclipse.draw2d.geometry.Point;
import org.eclipse.draw2d.geometry.Rectangle;
import org.eclipse.jface.action.IToolBarManager;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.IViewSite;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.part.ViewPart;

import com.github.jknack.antlr4ide.ui.railroad.actions.ExportToHtmlAction;
import com.github.jknack.antlr4ide.ui.railroad.actions.LinkWithEditorAction;
import com.github.jknack.antlr4ide.ui.railroad.actions.RailroadSelectionLinker;
import com.google.common.collect.Lists;
import com.google.inject.Inject;
import com.google.inject.Singleton;

/**
 * A railroad diagram view for Xtext grammars.
 *
 * @author Jan Koehnlein - Initial contribution and API
 */
@Singleton
public class RailroadView extends ViewPart {
    public static final String ID = "org.eclipse.xtext.xtext.ui.graph.view";

    @Inject
    private RailroadSynchronizer synchronizer;

    @Inject
    private RailroadSelectionProvider selectionProvider;

    @Inject
    private ExportToHtmlAction exportAction;

    @Inject
    private LinkWithEditorAction linkWithEditorAction;

    @Inject
    private RailroadSelectionLinker selectionLinker;

    private IFigure rootFigure;

    private FigureCanvas canvas;

    private IFigure contents;

    public RailroadView() {
    }

    @Override
    public void createPartControl(final Composite parent) {
        canvas = new FigureCanvas(parent, SWT.V_SCROLL | SWT.H_SCROLL);
        rootFigure = new Figure();
        rootFigure.addMouseListener(selectionProvider);
        rootFigure.setLayoutManager(new StackLayout());
        rootFigure.setVisible(true);
        canvas.setContents(rootFigure);
        getSite().setSelectionProvider(selectionProvider);
        createActions();
    }

    private void createActions() {
        IToolBarManager toolBarManager = getViewSite().getActionBars().getToolBarManager();
        toolBarManager.add(exportAction);
        toolBarManager.add(linkWithEditorAction);
        selectionLinker.activate();
    }

    @Override
    public void init(final IViewSite site) throws PartInitException {
        super.init(site);
        synchronizer.start(site);
    }

    @Override
    public void dispose() {
        selectionLinker.deactivate();
        synchronizer.stop(getSite());
        super.dispose();
    }

    public void setContents(final IFigure newContents) {
        Display.getDefault().asyncExec(new Runnable() {
            @Override
            public void run() {
                if (contents != null) {
                    if (contents.getParent() == rootFigure) {
                        rootFigure.remove(contents);
                    }
                }
                if (newContents != null) {
                    rootFigure.add(newContents);
                }
                rootFigure.validate();
                contents = newContents;
                exportAction.setEnabled(newContents != null);
            }
        });
    }

    public void clearView() {
        Display.getDefault().asyncExec(new Runnable() {
            @Override
            public void run() {
                @SuppressWarnings("unchecked")
                List<IFigure> children = rootFigure.getChildren();
                if (children != null) {
                    for (IFigure child : Lists.newArrayList(children)) {
                        rootFigure.remove(child);
                    }
                }
                exportAction.setEnabled(false);
            }
        });
    }

    public IFigure getContents() {
        return contents;
    }

    public IFigure findFigureAt(final Point location) {
        return rootFigure.findFigureAt(location);
    }

    public void reveal(final IFigure figure) {
        Viewport viewport = canvas.getViewport();
        Rectangle viewportBounds = viewport.getBounds().getCopy();
        viewportBounds.translate(viewport.getViewLocation());
        Rectangle figureBounds = figure.getBounds().getCopy();
        figure.translateToAbsolute(figureBounds);
        figureBounds.translate(viewport.getViewLocation());
        if (!viewportBounds.contains(figureBounds)) {
            int newX = viewportBounds.x;
            int newY = viewportBounds.y;
            if (viewportBounds.x > figureBounds.x) {
                newX = figureBounds.x;
            } else if (viewportBounds.x + viewportBounds.getRight().x < figureBounds.getRight().x) {
                newX = figureBounds.getRight().x - viewportBounds.width;
            }
            if (viewportBounds.y > figureBounds.y) {
                newY = figureBounds.y;
            } else if (viewportBounds.getBottom().y < figureBounds.getBottom().y) {
                newY = figureBounds.getBottom().y - viewportBounds.height;
            }
            canvas.scrollSmoothTo(newX, newY);
        }
    }

    @Override
    public void setFocus() {
        canvas.setFocus();
    }

    public Control getControl() {
        return canvas;
    }

}