Java tutorial
/******************************************************************************* * Copyright (c) 2015 UT-Battelle, LLC. * 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: * Jordan Deyton - Initial API and implementation and/or initial documentation * *******************************************************************************/ package org.eclipse.eavp.viz.service.connections.preferences; import java.util.ArrayList; import java.util.List; import org.eclipse.eavp.viz.datastructures.VizTableComponent; import org.eclipse.jface.action.Action; import org.eclipse.jface.action.ActionContributionItem; import org.eclipse.jface.action.IAction; import org.eclipse.jface.viewers.ColumnViewerToolTipSupport; import org.eclipse.jface.viewers.IElementComparer; import org.eclipse.jface.viewers.ISelectionChangedListener; import org.eclipse.jface.viewers.SelectionChangedEvent; import org.eclipse.jface.viewers.TableViewer; import org.eclipse.jface.window.ToolTip; import org.eclipse.swt.SWT; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Table; public class TableComponentComposite extends Composite { /** * The current {@code TableComponent} data model that is rendered in the * {@link #tableViewer}. */ private VizTableComponent tableComponent; /** * The JFace {@code Viewer} that displays the {@link #tableComponent}'s rows * as rows in an SWT {@link Table}. */ private TableViewer tableViewer; /** * Adds a new, default row to the {@link #tableComponent}. */ private Action addRowAction; /** * Removes all selected rows from the {@link #tableComponent}. */ private Action removeRowAction; // TODO Add an add wizard action. /** * A list to keep track of selected indices in the {@code TableComponent}. */ private final List<Integer> selectedIndices = new ArrayList<Integer>(); /** * The default constructor. * * @param parent * a widget which will be the parent of the new instance (cannot * be null) * @param style * the style of widget to construct */ public TableComponentComposite(Composite parent, int style) { super(parent, style); // Use a 2-column GridLayout. The table should get all excess space and // should be on the left. The action buttons should be on the right. setLayout(new GridLayout(2, false)); // Create the TableViewer. tableViewer = createTableViewer(this); tableViewer.getTable().setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true)); // Initialize the Actions. createActions(); // Create a Composite to contain the buttons. Use a vertical fill // layout. Composite buttons = new Composite(this, SWT.NONE); buttons.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, false, false)); buttons.setLayout(new FillLayout(SWT.VERTICAL)); // Create Buttons from the JFace Actions. new ActionContributionItem(addRowAction).fill(buttons); new ActionContributionItem(removeRowAction).fill(buttons); return; } /** * Creates the JFace {@code Action}s used to add or remove rows to or from * the {@link #tableComponent}. */ private void createActions() { // Create the add action. It will add a new, default row. addRowAction = new Action("+", IAction.AS_PUSH_BUTTON) { @Override public void run() { tableComponent.addRow(); } }; addRowAction.setToolTipText("Adds a new, default row."); // Create the remove action. It will remove all rows selected in the // TableViewer from the TableComponent. removeRowAction = new Action("-", IAction.AS_PUSH_BUTTON) { @Override public void run() { // The action should only be run once. setEnabled(false); // Delete all selected rows from the TableComponent. for (int i = selectedIndices.size() - 1; i >= 0; i--) { tableComponent.deleteRow(selectedIndices.get(i)); } selectedIndices.clear(); // Make sure the model knows there is no selection. tableComponent.setSelectedRows(new ArrayList<Integer>()); } }; removeRowAction.setToolTipText("Removes all selected rows."); removeRowAction.setEnabled(false); return; } /** * Creates a new {@code TableViewer} to show a {@link TableComponent}. * * @param parent * The containing {@code Composite}. * @return The created JFace {@code TableViewer}. */ private TableViewer createTableViewer(Composite parent) { // Create the TableViewer and the underlying Table Control. TableViewer viewer = new TableViewer(this, SWT.BORDER | SWT.MULTI | SWT.FULL_SELECTION | SWT.H_SCROLL | SWT.V_SCROLL); // Set some properties for the table. final Table table = viewer.getTable(); table.setHeaderVisible(true); table.setLinesVisible(true); // Set up the content provider for the viewer. Now the viewer's input // can be set. viewer.setContentProvider(new TableComponentContentProvider()); // Enable tool tips for the Table's cells. ColumnViewerToolTipSupport.enableFor(viewer, ToolTip.NO_RECREATE); // Add a selection listener to tell the TableComponent which rows are // selected. ISelectionChangedListener listener = new ISelectionChangedListener() { @Override public void selectionChanged(SelectionChangedEvent event) { // To delete rows (later), the TableComponent expects indices. // Thus, we must keep track of selected indicies by updating the // class' list. // To select rows, the TableComponent expects an // ArrayList<Integer> containing the row IDs, not indices. Thus, // we must convert the int[] of indices into an // ArrayList<Integer> of IDs to select. int[] selected = table.getSelectionIndices(); List<Integer> rowIds = tableComponent.getRowIds(); ArrayList<Integer> rows = new ArrayList<Integer>(selected.length); selectedIndices.clear(); for (int i : selected) { selectedIndices.add(i); rows.add(rowIds.get(i)); } tableComponent.setSelectedRows(rows); // Enable/disable the remove action if the selection is // non/empty. removeRowAction.setEnabled(!event.getSelection().isEmpty()); return; } }; viewer.addSelectionChangedListener(listener); // Use a custom comparer to just check references rather than calling // equals(Object), which causes strange behavior when multiple rows have // the same values. viewer.setComparer(new IElementComparer() { @Override public boolean equals(Object a, Object b) { return a == b; } @Override public int hashCode(Object element) { return element.hashCode(); } }); return viewer; } /** * Gets the current {@code TableComponent} data model that is rendered in * the {@link #tableViewer}. * * @return The current {@code TableComponent}. */ public VizTableComponent getTableComponent() { return tableComponent; } /** * Sets the current {@code TableComponent} data model that is rendered in * the {@link #tableViewer}. * * @param table * The new {@code TableComponent}. This value must not be * {@code null} and must have a row template. */ public void setTableComponent(VizTableComponent table) { // We cannot handle TableComponents with no template set. if (table == null || table.getRowTemplate() == null) { return; } // Otherwise, we should be able to add rows based on the set template. tableComponent = table; // Update the viewer's input. Display.getDefault().asyncExec(new Runnable() { @Override public void run() { // Make sure the remove action is disabled since the // TableComponent is new. removeRowAction.setEnabled(false); selectedIndices.clear(); // Set the TableViewer's input. tableViewer.setInput(tableComponent); } }); return; } }