| /******************************************************************************* |
| * Copyright (c) 2004, 2005 IBM Corporation and others. |
| * 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: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.jface.viewers.deferred; |
| |
| import java.util.Comparator; |
| |
| import org.eclipse.jface.util.Assert; |
| import org.eclipse.jface.viewers.AcceptAllFilter; |
| import org.eclipse.jface.viewers.IFilter; |
| import org.eclipse.jface.viewers.ILazyContentProvider; |
| import org.eclipse.jface.viewers.TableViewer; |
| import org.eclipse.jface.viewers.Viewer; |
| import org.eclipse.swt.widgets.Control; |
| import org.eclipse.swt.widgets.Table; |
| |
| /** |
| * Content provider that performs sorting and filtering in a background thread. |
| * Requires a <code>TableViewer</code> created with the <code>SWT.VIRTUAL</code> |
| * flag and an <code>IConcurrentModel</code> as input. |
| * <p> |
| * The sorter and filter must be set directly on the content provider. |
| * Any sorter or filter on the TableViewer will be ignored. |
| * </p> |
| * |
| * <p> |
| * The real implementation is in <code>BackgroundContentProvider</code>. This |
| * object is a lightweight wrapper that adapts the algorithm to work with |
| * <code>TableViewer</code>. |
| * </p> |
| * |
| * @since 3.1 |
| */ |
| public class DeferredContentProvider implements ILazyContentProvider { |
| |
| private int limit = -1; |
| private BackgroundContentProvider provider; |
| private Comparator sortOrder; |
| private IFilter filter = AcceptAllFilter.getInstance(); |
| private AbstractVirtualTable table; |
| |
| private static final class TableViewerAdapter extends AbstractVirtualTable { |
| |
| private TableViewer viewer; |
| |
| public TableViewerAdapter(TableViewer viewer) { |
| this.viewer = viewer; |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.deferred.AbstractVirtualTable#flushCache(java.lang.Object) |
| */ |
| public void clear(int index) { |
| viewer.clear(index); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.deferred.AbstractVirtualTable#replace(java.lang.Object, int) |
| */ |
| public void replace(Object element, int itemIndex) { |
| viewer.replace(element, itemIndex); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.deferred.AbstractVirtualTable#setItemCount(int) |
| */ |
| public void setItemCount(int total) { |
| viewer.setItemCount(total); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.deferred.AbstractVirtualTable#getItemCount() |
| */ |
| public int getItemCount() { |
| return viewer.getTable().getItemCount(); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.deferred.AbstractVirtualTable#getTopIndex() |
| */ |
| public int getTopIndex() { |
| return Math.max(viewer.getTable().getTopIndex() - 1, 0); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.deferred.AbstractVirtualTable#getVisibleItemCount() |
| */ |
| public int getVisibleItemCount() { |
| int start = getTopIndex(); |
| int itemCount = getItemCount(); |
| Table table = viewer.getTable(); |
| return Math.min(table.getBounds().height / table.getItemHeight() + 2, |
| itemCount - start); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.deferred.AbstractVirtualTable#getControl() |
| */ |
| public Control getControl() { |
| return viewer.getControl(); |
| } |
| |
| } |
| |
| /** |
| * Create a DeferredContentProvider with the given sort order. |
| * @param sortOrder a comparator that sorts the content. |
| */ |
| public DeferredContentProvider(Comparator sortOrder) { |
| this.sortOrder = sortOrder; |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.IContentProvider#dispose() |
| */ |
| public void dispose() { |
| setProvider(null); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer, java.lang.Object, java.lang.Object) |
| */ |
| public void inputChanged(Viewer viewer, Object oldInput, Object newInput) { |
| if (newInput == null) { |
| setProvider(null); |
| return; |
| } |
| |
| Assert.isTrue(newInput instanceof IConcurrentModel); |
| Assert.isTrue(viewer instanceof TableViewer); |
| IConcurrentModel model = (IConcurrentModel)newInput; |
| |
| this.table = new TableViewerAdapter((TableViewer)viewer); |
| |
| BackgroundContentProvider newProvider = new BackgroundContentProvider( |
| table, |
| model, sortOrder); |
| |
| setProvider(newProvider); |
| |
| newProvider.setLimit(limit); |
| newProvider.setFilter(filter); |
| } |
| |
| /** |
| * Sets the sort order for this content provider. This sort order takes priority |
| * over anything that was supplied to the <code>TableViewer</code>. |
| * |
| * @param sortOrder new sort order. The comparator must be able to support being |
| * used in a background thread. |
| */ |
| public void setSortOrder(Comparator sortOrder) { |
| Assert.isNotNull(sortOrder); |
| this.sortOrder = sortOrder; |
| if (provider != null) { |
| provider.setSortOrder(sortOrder); |
| } |
| } |
| |
| /** |
| * Sets the filter for this content provider. This filter takes priority over |
| * anything that was supplied to the <code>TableViewer</code>. The filter |
| * must be capable of being used in a background thread. |
| * |
| * @param toSet filter to set |
| */ |
| public void setFilter(IFilter toSet) { |
| this.filter = toSet; |
| if (provider != null) { |
| provider.setFilter(toSet); |
| } |
| } |
| |
| /** |
| * Sets the maximum number of rows in the table. If the model contains more |
| * than this number of elements, only the top elements will be shown based on |
| * the current sort order. |
| * |
| * @param limit maximum number of rows to show or -1 if unbounded |
| */ |
| public void setLimit(int limit) { |
| this.limit = limit; |
| if (provider != null) { |
| provider.setLimit(limit); |
| } |
| } |
| |
| /** |
| * Returns the current maximum number of rows or -1 if unbounded |
| * |
| * @return the current maximum number of rows or -1 if unbounded |
| */ |
| public int getLimit() { |
| return limit; |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jface.viewers.ILazyContentProvider#updateElement(int) |
| */ |
| public void updateElement(int element) { |
| if (provider != null) { |
| provider.checkVisibleRange(element); |
| } |
| } |
| |
| private void setProvider(BackgroundContentProvider newProvider) { |
| if (provider != null) { |
| provider.dispose(); |
| } |
| |
| provider = newProvider; |
| } |
| |
| } |