vaadin-framework/src/com/itmill/toolkit/ui/AbstractComponentContainer.java

/* *************************************************************************
 
                               IT Mill Toolkit 

               Development of Browser User Interfaces Made Easy

                    Copyright (C) 2000-2006 IT Mill Ltd
                     
   *************************************************************************

   This product is distributed under commercial license that can be found
   from the product package on license.pdf. Use of this product might 
   require purchasing a commercial license from IT Mill Ltd. For guidelines 
   on usage, see licensing-guidelines.html

   *************************************************************************
   
   For more information, contact:
   
   IT Mill Ltd                           phone: +358 2 4802 7180
   Ruukinkatu 2-4                        fax:   +358 2 4802 7181
   20540, Turku                          email:  info@itmill.com
   Finland                               company www: www.itmill.com
   
   Primary source for information and releases: www.itmill.com

   ********************************************************************** */

package com.itmill.toolkit.ui;

import java.lang.reflect.Method;
import java.util.LinkedList;
import java.util.Iterator;

/** Extension to {@link AbstractComponent} that defines the default
 * implementation for the methods in {@link ComponentContainer}. Basic UI
 * components that need to contain other components inherit this class to
 * easily qualify as a component container.
 * 
 * @author  IT Mill Ltd
 * @version @VERSION@
 * @since 3.0
 */
public abstract class AbstractComponentContainer 
extends AbstractComponent implements ComponentContainer {

	/** Constructs a new component container. */
	public AbstractComponentContainer() {
		super();
	}

    /** Removes all components from the container. This should probably be
     * reimplemented in extending classes for a more powerfu
     * implementation. 
     */
    public void removeAllComponents() {
        LinkedList l = new LinkedList();

		// Add all components
        for (Iterator i = getComponentIterator(); i.hasNext();)
        	l.add(i.next());
        	
        // Remove all component
        for (Iterator i = l.iterator(); i.hasNext();)
        	removeComponent((Component)i.next());
    }
    
    /* Moves all components from an another container into this container.
	 * Don't add a JavaDoc comment here, we use the default documentation
	 * from implemented interface.
	 */
	public void moveComponentsFrom(ComponentContainer source) {
		LinkedList components = new LinkedList();
		for (Iterator i = source.getComponentIterator(); i.hasNext();) 
			components.add(i.next());
		
		for (Iterator i = components.iterator(); i.hasNext();) {
			Component c = (Component) i.next();
			source.removeComponent(c);
			addComponent(c);
		}
    }
    
	/** Notifies all contained components that the container is attached to
	 * a window.
	 * 
	 * @see com.itmill.toolkit.ui.Component#attach()
	 */
	public void attach() {
		super.attach();
		
		for (Iterator i = getComponentIterator(); i.hasNext();)
			((Component)i.next()).attach();
	}

	/** Notifies all contained components that the container is detached
	 * from a window.
	 * 
	 * @see com.itmill.toolkit.ui.Component#detach()
	 */
	public void detach() {
		super.detach();
		
		for (Iterator i = getComponentIterator(); i.hasNext();)
			((Component)i.next()).detach();
	}


	/* Events ************************************************************ */

	private static final Method COMPONENT_ATTACHED_METHOD;
	private static final Method COMPONENT_DETACHED_METHOD;

	static {
		try {
			COMPONENT_ATTACHED_METHOD =
				ComponentAttachListener.class.getDeclaredMethod(
					"componentAttachedToContainer",
					new Class[] { ComponentAttachEvent.class });
			COMPONENT_DETACHED_METHOD =
				ComponentDetachListener.class.getDeclaredMethod(
					"componentDetachedFromContainer",
					new Class[] { ComponentDetachEvent.class });
		} catch (java.lang.NoSuchMethodException e) {
			// This should never happen
			throw new java.lang.RuntimeException();
		}
	}

	/* documented in interface */
	public void addListener(ComponentAttachListener listener) {
		addListener(ComponentContainer.ComponentAttachEvent.class, listener, COMPONENT_ATTACHED_METHOD);
	}

	/* documented in interface */
	public void addListener(ComponentDetachListener listener) {
		addListener(ComponentContainer.ComponentDetachEvent.class, listener, COMPONENT_DETACHED_METHOD);
	}

	/* documented in interface */
	public void removeListener(ComponentAttachListener listener) {
		removeListener(ComponentContainer.ComponentAttachEvent.class, listener, COMPONENT_ATTACHED_METHOD);
	}

	/* documented in interface */
	public void removeListener(ComponentDetachListener listener) {
		removeListener(ComponentContainer.ComponentDetachEvent.class, listener, COMPONENT_DETACHED_METHOD);
	}

	/** Fire component attached event. This should be called by the addComponent 
	 * methods after the component have been added to this container. 
	 * @param component The component that has been added to this container.
	 */
	protected void fireComponentAttachEvent(Component component) {
		fireEvent(new ComponentAttachEvent(this,component));
	}

	/** Fire component detached event. This should be called by the removeComponent 
	 * methods after the component have been removed from this container. 
	 * @param component The component that has been removed from this container.
	 */
	protected void fireComponentDetachEvent(Component component) {
		fireEvent(new ComponentAttachEvent(this,component));
	}
	
	/** This only implements the events and component parent calls. The extending
	 * classes must implement component list maintenance and call this method 
	 * after component list maintenance.
	 * @see com.itmill.toolkit.ui.ComponentContainer#addComponent(Component)
	 */
	public void addComponent(Component c) {
		c.setParent(this);
		fireComponentAttachEvent(c);
	}

	/** This only implements the events and component parent calls. The extending
	 * classes must implement component list maintenance and call this method 
	 * before component list maintenance.
	 * @see com.itmill.toolkit.ui.ComponentContainer#removeComponent(Component)
	 */
	public void removeComponent(Component c) {
		c.setParent(null);
		fireComponentDetachEvent(c);
	}
}