Java tutorial
/******************************************************************************* * Copyright (c) 2007, 2008 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 * Tom Schindl <tom.schindl@bestsolution.at> - initial API and implementation * - fix for bug 183850, 182652, 182800, 215069 *******************************************************************************/ package org.eclipse.emf.examples.library.databinding.common; import java.lang.reflect.Method; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.viewers.ColumnViewer; import org.eclipse.jface.viewers.FocusCellHighlighter; import org.eclipse.jface.viewers.ViewerCell; import org.eclipse.jface.viewers.ViewerRow; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.graphics.GC; import org.eclipse.swt.graphics.Rectangle; import org.eclipse.swt.widgets.Event; import org.eclipse.swt.widgets.Listener; import org.eclipse.swt.widgets.Widget; /** * A concrete implementation of {@link FocusCellHighlighter} using by setting * the control into owner draw mode and highlighting the currently selected * cell. To make the use this class you should create the control with the * {@link SWT#FULL_SELECTION} bit set * * This class can be subclassed to configure how the coloring of the selected * cell. * * @since 3.3 * */ public class FocusCellOwnerDrawHighlighter extends FocusCellHighlighter { /** * Create a new instance which can be passed to a * {@link TreeViewerFocusCellManager} * * @param viewer * the viewer */ public FocusCellOwnerDrawHighlighter(ColumnViewer viewer) { super(viewer); hookListener(viewer); } private void markFocusedCell(Event event, ViewerCell cell) { Color background = (cell.getControl().isFocusControl()) ? getSelectedCellBackgroundColor(cell) : getSelectedCellBackgroundColorNoFocus(cell); Color foreground = (cell.getControl().isFocusControl()) ? getSelectedCellForegroundColor(cell) : getSelectedCellForegroundColorNoFocus(cell); if (foreground != null || background != null || onlyTextHighlighting(cell)) { GC gc = event.gc; if (background == null) { background = cell.getItem().getDisplay().getSystemColor(SWT.COLOR_LIST_SELECTION); } if (foreground == null) { foreground = cell.getItem().getDisplay().getSystemColor(SWT.COLOR_LIST_SELECTION_TEXT); } gc.setBackground(background); gc.setForeground(foreground); if (onlyTextHighlighting(cell)) { Rectangle area = event.getBounds(); Rectangle rect = cell.getTextBounds(); if (rect != null) { area.x = rect.x; } gc.fillRectangle(area); } else { gc.fillRectangle(event.getBounds()); } event.detail &= ~SWT.SELECTED; } } private void removeSelectionInformation(Event event, ViewerCell cell) { // GC gc = event.gc; // gc.setBackground(cell.getViewerRow().getBackground( // cell.getColumnIndex())); // gc.setForeground(cell.getViewerRow().getForeground( // cell.getColumnIndex())); // gc.fillRectangle(cell.getBounds()); // event.detail &= ~SWT.SELECTED; } private void hookListener(final ColumnViewer viewer) { try { final Method m = ColumnViewer.class.getDeclaredMethod("getViewerRowFromItem", Widget.class); m.setAccessible(true); Listener listener = new Listener() { public void handleEvent(Event event) { if ((event.detail & SWT.SELECTED) > 0) { try { ViewerCell focusCell = getFocusCell(); ViewerRow row = (ViewerRow) m.invoke(viewer, event.item); Assert.isNotNull(row, "Internal structure invalid. Item without associated row is not possible."); //$NON-NLS-1$ ViewerCell cell = row.getCell(event.index); if (focusCell == null || !cell.equals(focusCell)) { removeSelectionInformation(event, cell); } else { markFocusedCell(event, cell); } } catch (Exception e) { // TODO: handle exception } } } }; viewer.getControl().addListener(SWT.EraseItem, listener); } catch (Exception e) { // TODO: handle exception } } /** * The color to use when rendering the background of the selected cell when * the control has the input focus * * @param cell * the cell which is colored * @return the color or <code>null</code> to use the default */ protected Color getSelectedCellBackgroundColor(ViewerCell cell) { return null; } /** * The color to use when rendering the foreground (=text) of the selected * cell when the control has the input focus * * @param cell * the cell which is colored * @return the color or <code>null</code> to use the default */ protected Color getSelectedCellForegroundColor(ViewerCell cell) { return null; } /** * The color to use when rendering the foreground (=text) of the selected * cell when the control has <b>no</b> input focus * * @param cell * the cell which is colored * @return the color or <code>null</code> to use the same used when * control has focus * @since 3.4 */ protected Color getSelectedCellForegroundColorNoFocus(ViewerCell cell) { return null; } /** * The color to use when rendering the background of the selected cell when * the control has <b>no</b> input focus * * @param cell * the cell which is colored * @return the color or <code>null</code> to use the same used when * control has focus * @since 3.4 */ protected Color getSelectedCellBackgroundColorNoFocus(ViewerCell cell) { return null; } /** * Controls whether the whole cell or only the text-area is highlighted * * @param cell * the cell which is highlighted * @return <code>true</code> if only the text area should be highlighted * @since 3.4 */ protected boolean onlyTextHighlighting(ViewerCell cell) { return false; } protected void focusCellChanged(ViewerCell newCell, ViewerCell oldCell) { super.focusCellChanged(newCell, oldCell); // Redraw new area if (newCell != null) { Rectangle rect = newCell.getBounds(); int x = newCell.getColumnIndex() == 0 ? 0 : rect.x; int width = newCell.getColumnIndex() == 0 ? rect.x + rect.width : rect.width; // 1 is a fix for Linux-GTK newCell.getControl().redraw(x, rect.y - 1, width, rect.height + 1, true); } if (oldCell != null) { Rectangle rect = oldCell.getBounds(); int x = oldCell.getColumnIndex() == 0 ? 0 : rect.x; int width = oldCell.getColumnIndex() == 0 ? rect.x + rect.width : rect.width; // 1 is a fix for Linux-GTK oldCell.getControl().redraw(x, rect.y - 1, width, rect.height + 1, true); } } }