listitem.java

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/* Listitem.java

{{IS_NOTE
	Purpose:
		
	Description:
		
	History:
		Wed Jun 15 17:38:52     2005, Created by tomyeh
}}IS_NOTE

Copyright (C) 2005 Potix Corporation. All Rights Reserved.

{{IS_RIGHT
	This program is distributed under GPL Version 2.0 in the hope that
	it will be useful, but WITHOUT ANY WARRANTY.
}}IS_RIGHT
*/
package org.zkoss.zul;

import java.util.Iterator;
import java.util.List;
import java.util.ArrayList;

import org.zkoss.lang.Objects;
import org.zkoss.util.logging.Log;
import org.zkoss.xml.HTMLs;

import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.UiException;

import org.zkoss.zul.impl.XulElement;

/**
 * A list item.
 *
 * @author tomyeh
 */
public class Listitem extends XulElement {
	private static final Log log = Log.lookup(Listitem.class);

	private Object _value;
	/** The index in the parent (only for implementation purpose). */
	private int _index = -1; //no parent at begining
	private boolean _selected, _disabled;
	/** whether the content of this item is loaded; used if
	 * the listbox owning this item is using a list model.
	 */
	private boolean _loaded;

	public Listitem() {
	}
	public Listitem(String label) {
		setLabel(label);
	}
	public Listitem(String label, Object value) {
		setLabel(label);
		setValue(value);
	}

	/** Returns the list box that it belongs to.
	 */
	public Listbox getListbox() {
		return (Listbox)getParent();
	}
	/** Returns whether the HTML's select tag is used.
	 */
	private final boolean inSelectMold() {
		final Listbox listbox = getListbox();
		return listbox != null && listbox.inSelectMold();
	}

	/** Returns the maximal length of each item's label.
	 * It is a shortcut of getParent().getMaxlength();
	 * Thus, it works only if the listbox's mold is "select".
	 */
	public int getMaxlength() {
		final Listbox listbox = getListbox();
		return listbox != null ? listbox.getMaxlength(): 0;
	}

	/** Returns the value.
	 * <p>Default: null.
	 * <p>Note: the value is application dependent, you can place
	 * whatever value you want.
	 * <p>If you are using listitem with HTML Form (and with
	 * the name attribute), it is better to specify a String-typed
	 * value.
	 */
	public Object getValue() {
		return _value;
	}
	/** Sets the value.
	 * @param value the value.
	 * <p>Note: the value is application dependent, you can place
	 * whatever value you want.
	 * <p>If you are using listitem with HTML Form (and with
	 * the name attribute), it is better to specify a String-typed
	 * value.
	 */
	public void setValue(Object value) {
		if (!Objects.equals(_value, value)) {
			_value = value;

			final Listbox listbox = getListbox();
			if (listbox != null)
				if (listbox.inSelectMold())
					smartUpdate("value", Objects.toString(_value));
				else if (listbox.getName() != null)
					smartUpdate("z.value", Objects.toString(_value));
		}
	}

	/** Returns whether it is disabled.
	 * <p>Default: false.
	 */
	public final boolean isDisabled() {
		return _disabled;
	}
	/** Sets whether it is disabled.
	 */
	public void setDisabled(boolean disabled) {
		if (_disabled != disabled) {
			if (disabled && !inSelectMold())
				throw new UnsupportedOperationException();

			_disabled = disabled;
			smartUpdate("disabled", _disabled);
		}
	}
	/** Returns whether it is selected.
	 * <p>Default: false.
	 */
	public boolean isSelected() {
		return _selected;
	}
	/** Sets whether it is selected.
	 */
	public void setSelected(boolean selected) {
		if (_selected != selected) {
			final Listbox listbox = (Listbox)getParent();
			if (listbox != null) {
				//Note: we don't update it here but let its parent does the job
				listbox.toggleItemSelection(this);
			} else {
				_selected = selected;
			}
		}
	}

	/** Returns the label of the {@link Listcell} it contains, or null
	 * if no such cell.
	 */
	public String getLabel() {
		final List cells = getChildren();
		return cells.isEmpty() ? null: ((Listcell)cells.get(0)).getLabel();
	}
	/** Sets the label of the {@link Listcell} it contains.
	 *
	 * <p>If it is not created, we automatically create it.
	 */
	public void setLabel(String label) {
		final List cells = getChildren();
		if (cells.isEmpty()) {
			final Listcell cell = new Listcell();
			cell.applyProperties();
			cell.setParent(this);
			cell.setLabel(label);
		} else {
			((Listcell)cells.get(0)).setLabel(label);
		}
	}

	/** Returns the src of the {@link Listcell} it contains, or null
	 * if no such cell.
	 */
	public String getSrc() {
		final List cells = getChildren();
		return cells.isEmpty() ? null: ((Listcell)cells.get(0)).getSrc();
	}
	/** Sets the src of the {@link Listcell} it contains.
	 *
	 * <p>If it is not created, we automatically create it.
	 *
	 * <p>The same as {@link #setImage}.
	 */
	public void setSrc(String src) {
		final List cells = getChildren();
		if (cells.isEmpty()) {
			final Listcell cell = new Listcell();
			cell.applyProperties();
			cell.setParent(this);
			cell.setSrc(src);
		} else {
			((Listcell)cells.get(0)).setSrc(src);
		}
	}
	/** Returns the image of the {@link Listcell} it contains.
	 *
	 * <p>The same as {@link #getImage}.
	 */
	public String getImage() {
		return getSrc();
	}
	/** Sets the image of the {@link Listcell} it contains.
	 *
	 * <p>If it is not created, we automatically create it.
	 *
	 * <p>The same as {@link #setSrc}.
	 */
	public void setImage(String image) {
		setSrc(image);
	}

	/** Returns the index of this item (aka., the order in the listbox).
	 */
	public final int getIndex() {
		return _index;
	}

	/** Sets whether the content of this item is loaded; used if
	 * the listbox owning this item is using a list model.
	 */
	/*package*/ final void setLoaded(boolean loaded) {
		if (loaded != _loaded) {
			_loaded = loaded;

			final Listbox listbox = getListbox();
			if (listbox != null && listbox.getModel() != null)
				smartUpdate("z.loaded", _loaded);
		}
	}
	/** Returns whether the content of this item is loaded; used if
	 * the listbox owning this item is using a list model.
	 */
	/*package*/ final boolean isLoaded() {
		return _loaded;
	}
	//-- Utilities for implementation only (called by Listbox) */
	/*package*/ final void setIndex(int index) {
		_index = index;
	}
	/*package*/ final void setSelectedDirectly(boolean selected) {
		_selected = selected;
	}

	//-- super --//
	/** Returns the style class.
	 * Note: 1) if not set (or setSclass(null), "item" is assumed;
	 * 2) if selected, it appends "sel" to super's getSclass().
	 */
	public String getSclass() {
		String scls = super.getSclass();
		if (scls == null) scls = "item";
		return isSelected() ? scls + "sel": scls;
	}

	//-- Component --//
	public void setParent(Component parent) {
		if (parent != null && !(parent instanceof Listbox))
			throw new UiException("Listitem's parent must be Listbox, not "+parent);
		super.setParent(parent);
	}
	public boolean insertBefore(Component child, Component insertBefore) {
		if (!(child instanceof Listcell))
			throw new UiException("Unsupported child for listitem: "+child);
		return super.insertBefore(child, insertBefore);
	}
	public void invalidate() {
		if (inSelectMold()) {
			//Both IE and Mozilla are buggy if we update options by outerHTML
			getParent().invalidate();
			return;
		}
		super.invalidate();
	}
	public void onChildAdded(Component child) {
		if (inSelectMold()) invalidate(); //if HTML-select, Listcell has no client part
		super.onChildAdded(child);
	}
	public void onChildRemoved(Component child) {
		if (inSelectMold()) invalidate(); //if HTML-select, Listcell has no client part
		super.onChildRemoved(child);
	}
	public String getOuterAttrs() {
		final StringBuffer sb =
			new StringBuffer(80).append(super.getOuterAttrs());

		if (inSelectMold()) {
			HTMLs.appendAttribute(sb, "value",  Objects.toString(_value));
			if (isDisabled())
				HTMLs.appendAttribute(sb, "disabled",  "disabled");
			if (isSelected())
				HTMLs.appendAttribute(sb, "selected", "selected");
		} else {
			final Listbox listbox = getListbox();
			if (listbox != null) {
				if (listbox.getName() != null)
					HTMLs.appendAttribute(sb, "z.value",  Objects.toString(_value));
				final Listitem sel = listbox.getSelectedItem();
				if (sel == this || (sel == null && getIndex() == 0))
					sb.append(" z.focus=\"true\"");
				if (listbox.getModel() != null)
					HTMLs.appendAttribute(sb, "z.loaded", _loaded);
			}
			if (isSelected())
				HTMLs.appendAttribute(sb, "z.sel", "true");

			final String clkattrs = getAllOnClickAttrs(false);
			if (clkattrs != null) sb.append(clkattrs);
		}
		return sb.toString();
	}
	//Clone//
	public Object clone() {
		final Listitem clone = (Listitem)super.clone();
		clone._index = -1;
			//note: we have to reset, since listbox.insertBefore assumes
			//that a parent-less listitem's index is -1
		return clone;
	}
}