secondo/Javagui/viewer/hoese/SimpleBackground.java

package viewer.hoese;

import java.awt.Rectangle;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.util.LinkedList;
import java.util.Properties;
import java.awt.geom.AffineTransform;


import javax.swing.JColorChooser;
import javax.swing.JComponent;

import sj.lang.ListExpr;
import tools.Reporter;

/**
 * This Background class homogeneously fills the visible background (the total
 * clipping area) with a user-defined color.
 *
 * @author Christian Duentgen
 *
 */
public class SimpleBackground extends Background {

	private static final long serialVersionUID = 4578057018487847324L;

	/**
	 * The simple constructor sets the background color to the JComponent's
	 * default background color.
	 */
	public SimpleBackground() {
		name = "SimpleBackground";
		license = "";
		backgroundcolor = null;
    backgroundChanged=true;
		useforbbox = false;
		bbox = null;
		listeners = new LinkedList<BackgroundListener>();
	}

	/**
	 * The simple constructor sets the background color to "white"
	 *
	 * @param c
	 *            The color to be used as background color;
	 */
	public SimpleBackground(Color c) {
		name = "SimpleBackground";
		license = "";
		backgroundcolor = c;
    backgroundChanged=true;
		useforbbox = false;
		bbox = null;
		listeners = new LinkedList<BackgroundListener>();
	}

	/**
	 * Creates a SimpleBackground, restoring it from a property.
	 *
	 * @param p
	 *            The properties to read from.
	 * @param datapath
	 *            The directory with additional data (not used).
	 */
	public SimpleBackground(Properties p, String datapath) {
		name = "SimpleBackground";
		license = "";
		backgroundcolor = null;
    backgroundChanged = true;
		useforbbox = false;
		bbox = null;
		listeners = new LinkedList<BackgroundListener>();
		setConfiguration(p, datapath);
	}

	/**
	 * Creates a SimpleBackground from a nested list and a data path.
	 *
	 * @param l
	 *            The nested list to read from.
	 * @param datapath
	 *            The directory with additional data (not used).
	 */
	public SimpleBackground(ListExpr l, String datapath) {
		name = "SimpleBackground";
		license = "";
		backgroundcolor = null;
    backgroundChanged=true;
		useforbbox = false;
		bbox = null;
		listeners = new LinkedList<BackgroundListener>();
		readFromList(l, datapath);
	}

	/**
	 * Constructs a SimpleBackground by interaction with the user.
	 *
	 * @param parent
	 *            The parent for the used dialog
	 */
	public SimpleBackground(JComponent parent) {
		name = "SimpleBackground";
		license = "";
		backgroundcolor = null;
    backgroundChanged=true;
		useforbbox = false;
		bbox = null;
		listeners = new LinkedList<BackgroundListener>();
		showConfigDialog(parent);
	}

	/**
	 * Opens a Dialog for choosing the background color. Informs all listeners
	 * about the change.
	 *
	 * @see viewer.hoese.Background#showConfigDialog(javax.swing.JComponent)
	 * @param parent
	 *            The parent of the dialog component used.
	 */
	@Override
	public void showConfigDialog(JComponent parent) {
		name = "SimpleBackground";
		license = "";
		useforbbox = false;
		bbox = null;
		if (listeners == null) {
			listeners = new LinkedList<BackgroundListener>();
		}
		Color selectedColor = JColorChooser.showDialog(null,
				"Choose the background color:", backgroundcolor);
    if(selectedColor!=null){
       if(!selectedColor.equals(backgroundcolor)){
          backgroundcolor = selectedColor;
          backgroundChanged = true;
       }
    }

		BackgroundChangedEvent evt = new BackgroundChangedEvent() {
			public Object getSource() {
				return SimpleBackground.this;
			}
		};
		informListeners(evt);
	}

	/**
	 * Set up the Background with parameters given as a Properties object. Can
	 * be used to restore the Background settings, e.g. from a file. All
	 * registered Listeners are informed. The image data is retrieved from files
	 * rooted at the given path.
	 * @param p
	 *            The Background settings to restore.
	 * @param backgrounddatapath
	 *            A path to a directory where additional data is stored in
	 *            files.
	 * @see viewer.hoese.Background#setConfiguration(java.util.Properties)
	 */
	@Override
	public void setConfiguration(Properties p, String backgrounddatapath) {
		license = "";
		useforbbox = false;
		bbox = null;
		if (listeners == null) {
			listeners = new LinkedList<BackgroundListener>();
		}
		super.setConfiguration(p, backgrounddatapath);
		backgroundcolor = null;
    backgroundChanged=true;
		String bcstring = p.getProperty(KEY_BGCOLOR, null);
		if(bcstring != null) {
			try {
				int rgb = Integer.parseInt(bcstring);
				backgroundcolor = new Color(rgb);
			} catch(Exception e) {
					Reporter.writeError("Could not set Background property: "
							+ KEY_BGCOLOR + " is not a valid RGB code).");
			}
		} else {
			Reporter.writeError("Could not set Background property: "
					+ KEY_BGCOLOR + " not found).");
		}
		BackgroundChangedEvent evt = new BackgroundChangedEvent() {
			public Object getSource() {
				return SimpleBackground.this;
			}
		};
		informListeners(evt);
	}

	/**
	 * Return the Background's settings as a Properties object. The Properties
	 * can be used to save Background settings for later reference. Additional
	 * data may be stored to files rooted at the given path.
	 * @param BackgroundDataPath
	 *            Path where to store the current image
	 * @return The Background's settings as a Properties object.
	 * @see viewer.hoese.Background#getConfiguration(java.lang.Object)
	 */
	@Override
	public Properties getConfiguration(String backgrounddatapath) {
		Properties p = super.getConfiguration(backgrounddatapath);
		if (p == null) {
			Reporter.writeError("ERROR: No property!");
		}
		int a = backgroundcolor.getRGB();
		p.setProperty(KEY_BGCOLOR, ("" + a));
		return p;
	}

	/**
	 * Paints the background as a filled rectangle.
	 * @see viewer.hoese.Background#paint()
	 * @param g
	 *            The Graphics object to paint to.
	 */
	@Override
	public void paint(JComponent parent, Graphics2D g, AffineTransform at, Rectangle2D rect) {
    if(parent!=null){
       if(backgroundChanged){
          backgroundChanged=false;
          parent.setBackground(backgroundcolor);
       }
    } else {
       Reporter.writeError("parent is null");
    }
  }

	/**
	 * This is a call-back method to be called by external objects requesting
	 * the Background to update it's internal data. Since the SimpleBackground
	 * does not register with any other structure, the implementation stays
	 * empty.
	 */
	@Override
	public void handleBackgroundDataChangedEvent(BackgroundChangedEvent evt) {
	}


  /** sets the background color used in this background **/
  public void setBackgroundColor(Color c){
     if(c==null && backgroundcolor==null){ // backgroundcolor not changed
        return;
     }
     if(backgroundcolor==null || c==null){
        backgroundChanged = true;
        backgroundcolor = c; 
        return;
     }
     if(!c.equals(backgroundcolor)){
        backgroundChanged = true;
        backgroundcolor = c; 
        return;
     }
  }


  public String toString(){
     return getClass().getName() + "[" + super.toString() + ", " + "backgroundcolor = " + backgroundcolor+"]";
  }

	/**
	 * The background color to be used.
	 */
	private Color backgroundcolor;
  private boolean backgroundChanged=true;

	public static final String KEY_BGCOLOR = "backgroundcolor";
}