BindRowRenderer.java

/* BindRowRenderer.java

	Purpose:
		
	Description:
		
	History:
		Aug 16, 2011 10:34:50 AM, Created by henrichen

Copyright (C) 2011 Potix Corporation. All Rights Reserved.
*/

package org.zkoss.bind.impl;

import org.zkoss.bind.Binder;
import org.zkoss.bind.sys.BinderCtrl;
import org.zkoss.bind.sys.TemplateResolver;
import org.zkoss.lang.Objects;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.UiException;
import org.zkoss.zk.ui.util.ForEachStatus;
import org.zkoss.zk.ui.util.Template;
import org.zkoss.zul.Attributes;
import org.zkoss.zul.Grid;
import org.zkoss.zul.Group;
import org.zkoss.zul.Groupfoot;
import org.zkoss.zul.Label;
import org.zkoss.zul.ListModel;
import org.zkoss.zul.Row;
import org.zkoss.zul.RowRenderer;
import org.zkoss.zul.Rows;

/**
 * Row renderer for binding.
 * @author henrichen
 * @since 6.0.0
 */
public class BindRowRenderer extends AbstractRenderer implements RowRenderer<Object> {
	private static final long serialVersionUID = 1463169907348730644L;

	public void render(final Row row, final Object data, final int index) {
		final Rows rows = (Rows) row.getParent();
		final Grid grid = (Grid) rows.getParent();
		final int size = grid.getModel().getSize();
		//B70-ZK-2555: in order to handle dynamic template name
		final String subtype = row instanceof Group ? "group" : row instanceof Groupfoot ? "groupfoot" : null;
		final Template tm = resolveTemplate(grid, row, data, index, size, "model", subtype);

		if (tm == null) {
			final Label label = newRenderLabel(Objects.toString(data));
			label.applyProperties();
			label.setParent(row);
			row.setValue(data);
		} else {
			final ForEachStatus iterStatus = new AbstractForEachStatus() { //provide iteration status in this context
				private static final long serialVersionUID = 1L;

				public int getIndex() {
					return index;
				}

				public Object getCurrent() {
					return data;
				}

				public Integer getEnd() {
					return size;
				}
			};

			final String var = (String) tm.getParameters().get(EACH_ATTR);
			final String varnm = var == null ? EACH_VAR : var; //var is not specified, default to "each"
			final String itervar = (String) tm.getParameters().get(STATUS_ATTR);
			final String itervarnm = itervar == null ? (var == null ? EACH_STATUS_VAR : varnm + STATUS_POST_VAR)
					: itervar; //provide default value if not specified

			//bug 1188, EL when nested var and itervar
			Object oldVar = grid.getAttribute(varnm);
			Object oldIter = grid.getAttribute(itervarnm);
			grid.setAttribute(varnm, data);
			grid.setAttribute(itervarnm, iterStatus);

			final Component[] items = filterOutShadows(rows, tm.create(rows, row, null, null));

			// Bug ZK-2882
			if (oldVar == null) {
				grid.removeAttribute(varnm);
			} else {
				grid.setAttribute(varnm, oldVar);
			}
			if (oldIter == null) {
				grid.removeAttribute(itervarnm);
			} else {
				grid.setAttribute(itervarnm, oldIter);
			}

			if (items.length != 1)
				throw new UiException("The model template must have exactly one row, not " + items.length);

			final Row nr = (Row) items[0];
			nr.setAttribute(BinderCtrl.VAR, varnm);

			// ZK-2552
			recordRenderedIndex(grid, items.length);

			nr.setAttribute(AbstractRenderer.IS_TEMPLATE_MODEL_ENABLED_ATTR, true);
			nr.setAttribute(AbstractRenderer.CURRENT_INDEX_RESOLVER_ATTR, new IndirectBinding(data) {
				public Binder getBinder() {
					return BinderUtil.getBinder(nr, true);
				}

				protected ListModel getModel() {
					return grid.getListModel();
				}

				public Component getComponent() {
					return nr;
				}
			});
			addItemReference(grid, nr, index, varnm); //kept the reference to the data, before ON_BIND_INIT

			nr.setAttribute(itervarnm, iterStatus);

			//sync open state
			if (nr instanceof Group && row instanceof Group) {
				((Group) nr).setOpen(((Group) row).isOpen());
			}

			//ZK-1787 When the viewModel tell binder to reload a list, the other component that bind a bean in the list will reload again
			//move TEMPLATE_OBJECT (was set in resoloveTemplate) to current for check in addTemplateTracking
			nr.setAttribute(TemplateResolver.TEMPLATE_OBJECT, row.removeAttribute(TemplateResolver.TEMPLATE_OBJECT));
			//add template dependency
			addTemplateTracking(grid, nr, data, index, size);

			if (nr.getValue() == null) //template might set it
				nr.setValue(data);
			row.setAttribute(Attributes.MODEL_RENDERAS, nr);
			//indicate a new row is created to replace the existent one
			row.detach();
		}
	}

	/** Returns the label for the cell generated by the default renderer.
	 */
	private static Label newRenderLabel(String value) {
		final Label label = new Label(value != null && value.length() > 0 ? value : " ");
		label.setPre(true); //to make sure   is generated, and then occupies some space
		return label;
	}
}