bundles/org.eclipse.emf.ecp.edit.swt/src/org/eclipse/emf/ecp/edit/internal/swt/controls/ECPFocusCellDrawHighlighter.java

/*******************************************************************************
 * Copyright (c) 2011-2013 EclipseSource Muenchen GmbH and others.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 * Edgar Mueller - initial API and implementation
 ******************************************************************************/
package org.eclipse.emf.ecp.edit.internal.swt.controls;

import org.eclipse.jface.viewers.CellLabelProvider;
import org.eclipse.jface.viewers.ColumnViewer;
import org.eclipse.jface.viewers.ColumnViewerEditor;
import org.eclipse.jface.viewers.ColumnViewerEditorActivationEvent;
import org.eclipse.jface.viewers.ColumnViewerEditorActivationListener;
import org.eclipse.jface.viewers.ColumnViewerEditorDeactivationEvent;
import org.eclipse.jface.viewers.FocusCellHighlighter;
import org.eclipse.jface.viewers.IColorProvider;
import org.eclipse.jface.viewers.ViewerCell;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Table;

/**
 * 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
 *
 * <p>
 * <strong>RAP specific:</strong> despite its name that was taken as-is from JFace/RCP to ease single-sourcing, this
 * class does not use custom drawing to highlight the focused cell. <br />
 * The focused cell is displayed using the selection colors of the system.
 * </p>
 *
 * This class can be subclassed to configure how the coloring of the selected
 * cell.
 *
 * @since 1.2
 *
 */
public class ECPFocusCellDrawHighlighter extends FocusCellHighlighter {

	private final ColumnViewer viewer;

	/**
	 * Create a new instance which can be passed to a.
	 *
	 * @param viewer
	 *            the viewer
	 */
	public ECPFocusCellDrawHighlighter(ColumnViewer viewer) {
		super(viewer);
		this.viewer = viewer;
		// hookListener(viewer);
		// RAP [if]
		viewer.getControl().setData(Table.class.getName() + "#alwaysHideSelection", Boolean.TRUE); //$NON-NLS-1$
	}

	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());
			// }
			cell.setBackground(background);
			cell.setForeground(foreground);

			// 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;
		Color cellBackground = null;
		Color cellForeground = null;
		final CellLabelProvider labelProvider = viewer.getLabelProvider(cell.getColumnIndex());
		if (labelProvider instanceof IColorProvider) {
			final IColorProvider columnLabelProvider = (IColorProvider) labelProvider;
			cellBackground = columnLabelProvider.getBackground(cell.getElement());
			cellForeground = columnLabelProvider.getForeground(cell.getElement());
		}
		cell.setBackground(cellBackground);
		cell.setForeground(cellForeground);
	}

	// private void hookListener(final ColumnViewer viewer) {
	//
	// Listener listener = new Listener() {
	//
	// public void handleEvent(Event event) {
	// // if ((event.detail & SWT.SELECTED) > 0) {
	// ViewerCell focusCell = getFocusCell();
	// ViewerRow row = viewer.getViewerRowFromItem(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);
	// // }
	//
	// focusCellChanged( focusCell );
	// }
	//
	// };
	// // viewer.getControl().addListener(SWT.EraseItem, listener);
	// viewer.getControl().addListener(SWT.KeyDown, listener);
	// viewer.getControl().addListener(SWT.MouseDown, listener);
	// }

	/**
	 * 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
	 */
	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
	 */
	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
	 */
	protected boolean onlyTextHighlighting(ViewerCell cell) {
		// return false;
		return true;
	}

	@Override
	protected void init() {
		final ColumnViewerEditorActivationListener listener = new ColumnViewerEditorActivationListener() {
			@Override
			public void afterEditorActivated(ColumnViewerEditorActivationEvent e) {
			}

			@Override
			public void afterEditorDeactivated(ColumnViewerEditorDeactivationEvent e) {
				focusCellChanged(getFocusCell(), null);
			}

			@Override
			public void beforeEditorActivated(ColumnViewerEditorActivationEvent e) {
			}

			@Override
			public void beforeEditorDeactivated(ColumnViewerEditorDeactivationEvent e) {
			}
		};
		final ColumnViewerEditor editor = viewer.getColumnViewerEditor();
		editor.addEditorActivationListener(listener);
	}

	@Override
	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);
		// }
		if (oldCell != null) {
			removeSelectionInformation(null, oldCell);
		}
		if (newCell != null) {
			markFocusedCell(null, newCell);
		}
	}
}