package graph.filter;
import graph.*;
import java.awt.*;

/**
 * A simple dialog box for manipulating configuration information of
 * a filter.  It is constructed out of an array of FilterProps, each
 * of which provide their own GUI's.  If the user hits the <i>done</i>
 * button, the properties are committed.  If the user hits the
 * <i>cancel</i> button the changes are discarded. <p>
 *
 * This class is provided as a convenience to make things easier for
 * filter writers.  However, the Filter class itself simply returns
 * a Frame to configure itself, so special filters may have more
 * custom configuration GUI's where appropriate.
 *
 * @see Filter
 * @see FilterProp
 * @author Michael Shilman (michaels@eecs.berkeley.edu)
 * @version $Id$
 */
public class FilterConfig extends Frame {
	/**
	 * The array of properties that are configured by
	 * this dialog.
	 */
	protected FilterProp[] m_props = null;
	protected Button m_done = null;
	protected Button m_cancel = null;
	
	/**
	 * Builds the dialog box for this dialog so that the
	 * user can configure the filter parameters.
	 */
	FilterConfig(FilterProp[] props) {
		m_props = props;
		setLayout(new GridLayout(m_props.length+2, 1));
		for(int i = 0; i < m_props.length; i++) {
			add(m_props[i]);
		}
		m_done = new Button("Done");
		add(m_done);
		m_cancel = new Button("Cancel");
		add(m_cancel);

	}
	
	/**
	 * Commit the changes to each of the properties.
	 */
	public void update() {
		for(int i = 0; i < m_props.length; i++) {
			m_props[i].update();
		}
	}
	
	public boolean action(Event evt, Object what) {
		if(evt.target == m_done) {
			update();
			hide();
			return true;
		}
		else if(evt.target == m_cancel) {
			hide();
			return true;
		}
		return super.action(evt, what);
	}
}