FlatDataLoader.java

/*******************************************************************************
 * Copyright (c) 2009-2010, G. Weirich and Elexis
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    G. Weirich - initial implementation
 * 
 *******************************************************************************/

package ch.elexis.core.ui.actions;

import java.util.HashMap;
import java.util.List;

import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.viewers.ILazyContentProvider;
import org.eclipse.jface.viewers.TableViewer;

import ch.elexis.core.ui.UiDesk;
import ch.elexis.core.ui.util.viewers.CommonViewer;
import ch.elexis.core.ui.util.viewers.ViewerConfigurer.ControlFieldProvider;
import ch.elexis.data.PersistentObject;
import ch.elexis.data.Query;

/**
 * A PersistentObjectLoader for flat tables. This is also an ILazyContentProvider for Structured
 * Viewers and a ContentProvider for @see CommonViewer
 * 
 * @author Gerry
 * 
 */
public class FlatDataLoader extends PersistentObjectLoader implements ILazyContentProvider {
	//private static final String LOADMESSAGE = "Lade Daten..."; //$NON-NLS-1$
	private List<? extends PersistentObject> raw = null;
	private List<? extends PersistentObject> filtered = null;
	
	public FlatDataLoader(CommonViewer cv, Query<? extends PersistentObject> qbe){
		super(cv, qbe);
	}
	
	/**
	 * Constructor without CommonViewer. Do not in Connection with CommonViewers
	 * 
	 * @param qbe
	 */
	public FlatDataLoader(Query<? extends PersistentObject> qbe){
		super(null, qbe);
	}
	
	/**
	 * From @see DelayableJob.IWorker
	 */
	public IStatus work(IProgressMonitor monitor, HashMap<String, Object> params){
		if (isSuspended()) {
			return Status.CANCEL_STATUS;
		}
		final TableViewer tv = (TableViewer) cv.getViewerWidget();
		if (filtered != null) {
			filtered.clear();
		}
		filtered = null;
		setQuery();
		applyQueryFilters();
		if (orderFields != null) {
			qbe.orderBy(false, orderFields);
		}
		if (monitor.isCanceled()) {
			return Status.CANCEL_STATUS;
		}
		raw = qbe.execute();
		if (monitor.isCanceled()) {
			return Status.CANCEL_STATUS;
		}
		UiDesk.asyncExec(new Runnable() {
			public void run(){
				// Avoid access to disposed table
				if (tv != null && !tv.getTable().isDisposed()) {
					tv.setItemCount(0);
					filtered = raw;
					tv.setItemCount(raw.size());
				}
			}
		});
		
		return Status.OK_STATUS;
	}
	
	public void setResult(List<PersistentObject> res){
		raw = res;
	}
	
	/**
	 * prepare the query so it returns the appropriate Objects on execute(). The default
	 * implemetation lets the ControlFieldProvider set the query. Subclasses may override
	 */
	protected void setQuery(){
		qbe.clear();
		ControlFieldProvider cfp = cv.getConfigurer().getControlFieldProvider();
		if (cfp != null) {
			cfp.setQuery(qbe);
		}
	}
	
	public void updateElement(int index){
		if (filtered != null) {
			if (index >= 0 && index < filtered.size()) {
				Object o = filtered.get(index);
				if (o != null) {
					TableViewer tv = (TableViewer) cv.getViewerWidget();
					tv.replace(filtered.get(index), index);
				}
			}
		}
	}
	
}