listbox.java

ZK 基础介绍 功能操作 模块 结合数据库操作

	public void setName(String name) {
		if (name != null && name.length() == 0) name = null;
		if (!Objects.equals(_name, name)) {
			_name = name;
			if (inSelectMold()) smartUpdate("name", _name);
			else if (_name != null) smartUpdate("z.name", _name);
			else invalidate(); //1) generate _value; 2) add submit listener
		}
	}

	/** Returns a live list of all {@link Listitem}.
	 * By live we mean you can add or remove them directly with
	 * the List interface. In other words, you could add or remove
	 * an item by manipulating the returned list directly.
	 */
	public List getItems() {
		return _items;
	}
	/** Returns the number of items.
	 */
	public int getItemCount() {
		return _items.size();
	}
	/** Returns the item at the specified index.
	 *
	 * <p>Note: if live data is used ({@link #getModel} is not null),
	 * the returned item might NOT be loaded yet.
	 * To ensure it is loaded, you have to invoke {@link #renderItem}.
	 */
	public Listitem getItemAtIndex(int index) {
		return (Listitem)_items.get(index);
	}
	/** Returns the index of the specified item, or -1 if not found.
	 */
	public int getIndexOfItem(Listitem item) {
		return item == null ? -1: item.getIndex();
	}

	/** Returns the index of the selected item (-1 if no one is selected).
	 */
	public int getSelectedIndex() {
		return _jsel;
	}
	/** Deselects all of the currently selected items and selects
	 * the item with the given index.
	 */
	public void setSelectedIndex(int jsel) {
		if (jsel >= _items.size())
			throw new UiException("Out of bound: "+jsel+" while size="+_items.size());

		if (jsel < -1) 
			jsel = -1;
		if (jsel < 0) { //unselct all
			clearSelection();
		} else if (jsel != _jsel
		|| (_multiple && _selItems.size() > 1)) {
			for (Iterator it = _selItems.iterator(); it.hasNext();) {
				final Listitem item = (Listitem)it.next();
				item.setSelectedDirectly(false);
			}
			_selItems.clear();

			_jsel = jsel;
			final Listitem item = getItemAtIndex(_jsel);
			item.setSelectedDirectly(true);
			_selItems.add(item);
			if (inSelectMold())
				smartUpdate("selectedIndex", Integer.toString(_jsel));
			else
				smartUpdate("select", item.getUuid());
				//Bug 1734950: don't count on index (since it may change)
				//On the other hand, it is OK with select-mold since
				//it invalidates if items are added or removed
		}
	}

	/**  Deselects all of the currently selected items and selects
	 * the given item.
	 * <p>It is the same as {@link #setSelectedItem}.
	 * @param item the item to select. If null, all items are deselected.
	 */
	public void selectItem(Listitem item) {
		if (item == null) {
			setSelectedIndex(-1);
		} else {
			if (item.getParent() != this)
				throw new UiException("Not a child: "+item);
			if (_multiple || !item.isSelected())
				setSelectedIndex(item.getIndex());
		}
	}
	/** Selects the given item, without deselecting any other items
	 * that are already selected..
	 */
	public void addItemToSelection(Listitem item) {
		if (item.getParent() != this)
			throw new UiException("Not a child: "+item);

		if (!item.isSelected()) {
			if (!_multiple) {
				selectItem(item);
			} else {
				if (item.getIndex() < _jsel || _jsel < 0) {
					_jsel = item.getIndex();
					if (!inSelectMold()) smartUpdate("z.selId", getSelectedId());
				}
				item.setSelectedDirectly(true);
				_selItems.add(item);
				if (inSelectMold()) {
					item.smartUpdate("selected", true);
				} else {
					smartUpdateSelection();
				}
			}
		}
	}
	/**  Deselects the given item without deselecting other items.
	 */
	public void removeItemFromSelection(Listitem item) {
		if (item.getParent() != this)
			throw new UiException("Not a child: "+item);

		if (item.isSelected()) {
			if (!_multiple) {
				clearSelection();
			} else {
				final int oldSel = _jsel;
				item.setSelectedDirectly(false);
				_selItems.remove(item);
				fixSelectedIndex(0);
				if (inSelectMold()) {
					item.smartUpdate("selected", false);
				} else {
					smartUpdateSelection();
					if (oldSel != _jsel)
						smartUpdate("z.selId", getSelectedId());
				}
			}
		}
	}
	/** Note: we have to update all selection at once, since addItemToSelection
	 * and removeItemFromSelection might be called interchangeably.
	 */
	private void smartUpdateSelection() {
		final StringBuffer sb = new StringBuffer(80);
		for (Iterator it = _selItems.iterator(); it.hasNext();) {
			if (sb.length() > 0) sb.append(',');
			sb.append(((Listitem)it.next()).getUuid());
		}
		smartUpdate("chgSel", sb.toString());
	}
	/** If the specified item is selected, it is deselected.
	 * If it is not selected, it is selected. Other items in the list box
	 * that are selected are not affected, and retain their selected state.
	 */
	public void toggleItemSelection(Listitem item) {
		if (item.isSelected()) removeItemFromSelection(item);
		else addItemToSelection(item);
	}
	/** Clears the selection.
	 */
	public void clearSelection() {
		if (!_selItems.isEmpty()) {
			for (Iterator it = _selItems.iterator(); it.hasNext();) {
				final Listitem item = (Listitem)it.next();
				item.setSelectedDirectly(false);
			}
			_selItems.clear();
			_jsel = -1;
			if (inSelectMold())
				smartUpdate("selectedIndex", "-1");
			else
				smartUpdate("select", "");
				//Bug 1734950: don't count on index (since it may change)
		}
	}
	/** Selects all items.
	 */
	public void selectAll() {
		if (!_multiple)
			throw new UiException("Appliable only to the multiple seltype: "+this);

		if (_items.size() != _selItems.size()) {
			for (Iterator it = _items.iterator(); it.hasNext();) {
				final Listitem item = (Listitem)it.next();
				_selItems.add(item);
				item.setSelectedDirectly(true);
			}
			_jsel = _items.isEmpty() ? -1: 0;
			smartUpdate("selectAll", "true");
		}
	}

	/** Returns the selected item.
	 *
	 * <p>Note: if live data is used ({@link #getModel} is not null),
	 * the returned item might NOT be loaded yet.
	 * To ensure it is loaded, you have to invoke {@link #renderItem}.
	 */
	public Listitem getSelectedItem() {
		return  _jsel >= 0 ?
			_jsel > 0 && _selItems.size() == 1 ? //optimize for performance
				(Listitem)_selItems.iterator().next():
				getItemAtIndex(_jsel): null;
	}
	/**  Deselects all of the currently selected items and selects
	 * the given item.
	 * <p>It is the same as {@link #selectItem}.
	 */
	public void setSelectedItem(Listitem item) {
		selectItem(item);
	}

	/** Returns all selected items.
	 *
	 * <p>Note: if live data is used ({@link #getModel} is not null),
	 * the returned item might NOT be loaded yet.
	 * To ensure it is loaded, you have to invoke {@link #renderItem}.
	 */
	public Set getSelectedItems() {
		return _roSelItems;
	}
	/** Returns the number of items being selected.
	 */
	public int getSelectedCount() {
		return _selItems.size();
	}

	/** Appends an item.
	 *
	 * <p>Note: if live data is used ({@link #getModel} is not null),
	 * the returned item might NOT be loaded yet.
	 * To ensure it is loaded, you have to invoke {@link #renderItem}.
	 */
	public Listitem appendItem(String label, String value) {
		final Listitem item = new Listitem(label, value);
		item.applyProperties();
		item.setParent(this);
		return item;
	}
	/**  Removes the child item in the list box at the given index.
	 *
	 * <p>Note: if live data is used ({@link #getModel} is not null),
	 * the returned item might NOT be loaded yet.
	 * To ensure it is loaded, you have to invoke {@link #renderItem}.
	 *
	 * @return the removed item.
	 */
	public Listitem removeItemAt(int index) {
		final Listitem item = getItemAtIndex(index);
		removeChild(item);
		return item;
	}

	//--Paging--//
	/** Returns the paging controller, or null if not available.
	 * Note: the paging controller is used only if {@link #getMold} is "paging".
	 *
	 * <p>If mold is "paging", this method never returns null, because
	 * a child paging controller is created automcatically (if not specified
	 * by developers with {@link #setPaginal}).
	 *
	 * <p>If a paging controller is specified (either by {@link #setPaginal},
	 * or by {@link #setMold} with "paging"),
	 * the listbox will rely on the paging controller to handle long-content
	 * instead of scrolling.
	 */
	public Paginal getPaginal() {
		return _pgi;
	}
	/* Specifies the paging controller.
	 * Note: the paging controller is used only if {@link #getMold} is "paging".
	 *
	 * <p>It is OK, though without any effect, to specify a paging controller
	 * even if mold is not "paging".
	 *
	 * @param pgi the paging controller. If null and {@link #getMold} is "paging",
	 * a paging controller is created automatically as a child component
	 * (see {@link #getPaging}).
	 */
	public void setPaginal(Paginal pgi) {
		if (!Objects.equals(pgi, _pgi)) {
			final Paginal old = _pgi;
			_pgi = pgi;

			if (inPagingMold()) {
				if (old != null) removePagingListener(old);
				if (_pgi == null) {
					if (_paging != null) _pgi = _paging;
					else newInternalPaging();
				} else { //_pgi != null
					if (_pgi != _paging) {
						if (_paging != null) _paging.detach();
						_pgi.setTotalSize(getItemCount());
						addPagingListener(_pgi);
					}
				}
			}
		}
	}
	/** Creates the internal paging component.
	 */
	private void newInternalPaging() {
		assert D.OFF || inPagingMold(): "paging mold only";
		assert D.OFF || (_paging == null && _pgi == null);

		final Paging paging = new Paging();
		paging.setAutohide(true);
		paging.setDetailed(true);
		paging.setTotalSize(getItemCount());
		paging.setParent(this);
		addPagingListener(_pgi);
	}
	/** Adds the event listener for the onPaging event. */
	private void addPagingListener(Paginal pgi) {
		if (_pgListener == null)
			_pgListener = new EventListener() {
				public void onEvent(Event event) {
					final PagingEvent evt = (PagingEvent)event;
					Events.postEvent(
						new PagingEvent(evt.getName(),
							Listbox.this, evt.getPageable(), evt.getActivePage()));
				}
			};
		pgi.addEventListener(ZulEvents.ON_PAGING, _pgListener);

		if (_pgImpListener == null)
			_pgImpListener = new EventListener() {
	public void onEvent(Event event) {
		if (_model != null && inPagingMold()) {
			final Renderer renderer = new Renderer();
			try {
				final Paginal pgi = getPaginal();
				int pgsz = pgi.getPageSize();
				final int ofs = pgi.getActivePage() * pgsz;
				for (final Iterator it = getItems().listIterator(ofs);
				--pgsz >= 0 && it.hasNext();)
					renderer.render((Listitem)it.next());
			} catch (Throwable ex) {
				renderer.doCatch(ex);
			} finally {
				renderer.doFinally();
			}
		}
		invalidate();
	}
			};
		pgi.addEventListener("onPagingImpl", _pgImpListener);
	}
	/** Removes the event listener for the onPaging event. */
	private void removePagingListener(Paginal pgi) {
		pgi.removeEventListener(ZulEvents.ON_PAGING, _pgListener);
		pgi.removeEventListener("onPagingImpl", _pgImpListener);
	}

	/** Returns the child paging controller that is created automatically,
	 * or null if mold is not "paging", or the controller is specified externally
	 * by {@link #setPaginal}.
	 */
	public Paging getPaging() {
		return _paging;
	}
	/** Returns the page size, aka., the number items per page.
	 * @exception IllegalStateException if {@link #getPaginal} returns null,
	 * i.e., mold is not "paging" and no external controller is specified.
	 */
	public int getPageSize() {
		if (_pgi == null)
			throw new IllegalStateException("Available only the paging mold");
		return _pgi.getPageSize();
	}
	/** Sets the page size, aka., the number items per page.
	 * @exception IllegalStateException if {@link #getPaginal} returns null,
	 * i.e., mold is not "paging" and no external controller is specified.
	 */
	public void setPageSize(int pgsz) {
		if (_pgi == null)
			throw new IllegalStateException("Available only the paging mold");
		_pgi.setPageSize(pgsz);
	}

	/** Returns whether this listbox is in the paging mold.
	 */
	/*package*/ boolean inPagingMold() {
		return "paging".equals(getMold());
	}

	/** Returns the index of the first visible child.
	 * <p>Used only for component development, not for application developers.
	 */
	public int getVisibleBegin() {
		if (!inPagingMold())
			return 0;
		final Paginal pgi = getPaginal();
		return pgi.getActivePage() * pgi.getPageSize();
	}
	/** Returns the index of the last visible child.
	 * <p>Used only for component development, not for application developers.
	 */
	public int getVisibleEnd() {
		if (!inPagingMold())
			return Integer.MAX_VALUE;
		final Paginal pgi = getPaginal();
		return (pgi.getActivePage() + 1) * pgi.getPageSize() - 1; //inclusive
	}

	/** Returns the style class for the odd rows.
	 * <p>Default: odd.
	 * @since 3.0.0
	 */
	public String getOddRowSclass() {
		return _scOddRow;
	}
	/** Sets the style class for the odd rows.
	 * If the style class doesn't exist, the striping effect disappears.
	 * You can provide different effects by providing the proper style
	 * classes.
	 * @since 3.0.0
	 */
	public void setOddRowSclass(String scls) {
		if (scls != null && scls.length() == 0) scls = null;
		if (!Objects.equals(_scOddRow, scls)) {
			_scOddRow = scls;
			smartUpdate("z.scOddRow", scls);
		}
	}

	//-- Component --//
	public void smartUpdate(String attr, String value) {
		if (!_noSmartUpdate) super.smartUpdate(attr, value);
	}
	public void onChildAdded(Component child) {
		super.onChildAdded(child);
		if (inSelectMold()) invalidate();
			//Both IE and Mozilla are buggy if we insert options by innerHTML
		else if(inPagingMold() && (child instanceof Listitem))
			_pgi.setTotalSize(getItemCount());
	}
	public void onChildRemoved(Component child) {
		super.onChildRemoved(child);
		if (inSelectMold()) invalidate();
			//Both IE and Mozilla are buggy if we remove options by outerHTML
			//CONSIDER: use special command to remove items
			//Cons: if user remove a lot of items it is slower
		else if(inPagingMold() && (child instanceof Listitem))
			_pgi.setTotalSize(getItemCount());
	}
	public boolean insertBefore(Component newChild, Component refChild) {
		if (newChild instanceof Listitem) {
			//first: listhead or auxhead
			//last two: listfoot and paging
			if (refChild != null && refChild.getParent() != this)
				refChild = null; //Bug 1649625: it becomes the last child
			if (refChild != null
			&& (refChild == _listhead || refChild instanceof Auxhead))
				refChild = getChildren().size() > _hdcnt ?
					(Component)getChildren().get(_hdcnt): null;

			refChild = fixRefChildBeforeFoot(refChild);