PagableFreeformRootEditPart.java

package org.insightech.er.editor.controller.editpart.element;

import org.eclipse.draw2d.ColorConstants;
import org.eclipse.draw2d.Graphics;
import org.eclipse.draw2d.geometry.Rectangle;
import org.eclipse.gef.editparts.GridLayer;
import org.eclipse.gef.editparts.ScalableFreeformRootEditPart;
import org.eclipse.swt.graphics.Color;
import org.insightech.er.editor.model.ERDiagram;
import org.insightech.er.editor.model.settings.PageSetting;

public class PagableFreeformRootEditPart extends ScalableFreeformRootEditPart {

	private ERDiagram diagram;

	public PagableFreeformRootEditPart(ERDiagram diagram) {
		this.diagram = diagram;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected GridLayer createGridLayer() {
		return new PagableGridLayer();
	}

	private class PagableGridLayer extends GridLayer {

		private int i = 0;

		/**
		 * {@inheritDoc}
		 */
		@Override
		protected void paintGrid(Graphics g) {
			super.paintGrid(g);

			Rectangle clip = g.getClip(Rectangle.SINGLETON);

			PageSetting pageSetting = diagram.getPageSetting();

			int width = pageSetting.getWidth();
			int height = pageSetting.getHeight();

			Rectangle rect = clip;

			Color color = g.getForegroundColor();
			g.setForegroundColor(ColorConstants.lightGray);

			int startX = rect.x;
			if (startX > 0) {
				startX = 0;
			}
			int startY = rect.y;
			if (startY > 0) {
				startY = 0;
			}

			for (int i = startX; i < rect.x + rect.width; i += width) {
				g.drawLine(i, rect.y, i, rect.y + rect.height);
			}

			for (int i = startY; i < rect.y + rect.height; i += height) {
				g.drawLine(rect.x, i, rect.x + rect.width, i);
			}

			g.setForegroundColor(color);

			i++;
			if (i > 0) {
				i = -1;
				repaint();
			}
		}
	}
}