org.eclipse.nebula.widgets.nattable.core/src/org/eclipse/nebula/widgets/nattable/tree/config/TreeLayerExpandCollapseKeyBindings.java

/*******************************************************************************
 * Copyright (c) 2014, 2020 Roman Flueckiger, Dirk Fauth.
 *
 * This program and the accompanying materials are made
 * available under the terms of the Eclipse Public License 2.0
 * which is available at https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Roman Flueckiger <roman.flueckiger@mac.com> - initial API and implementation
 ******************************************************************************/
package org.eclipse.nebula.widgets.nattable.tree.config;

import static org.eclipse.nebula.widgets.nattable.tree.config.DefaultTreeLayerConfiguration.TREE_COLLAPSED_CONFIG_TYPE;
import static org.eclipse.nebula.widgets.nattable.tree.config.DefaultTreeLayerConfiguration.TREE_EXPANDED_CONFIG_TYPE;
import static org.eclipse.nebula.widgets.nattable.ui.matcher.SelectionAnchorCellLabelKeyEventMatcher.anchorLabel;

import org.eclipse.nebula.widgets.nattable.config.AbstractUiBindingConfiguration;
import org.eclipse.nebula.widgets.nattable.layer.IUniqueIndexLayer;
import org.eclipse.nebula.widgets.nattable.selection.SelectionLayer;
import org.eclipse.nebula.widgets.nattable.tree.action.TreeExpandCollapseKeyAction;
import org.eclipse.nebula.widgets.nattable.ui.binding.UiBindingRegistry;
import org.eclipse.nebula.widgets.nattable.ui.matcher.KeyEventMatcher;
import org.eclipse.swt.SWT;

/**
 * A default configuration that can be used as an addition for a NatTable with
 * both a {@link org.eclipse.nebula.widgets.nattable.tree.TreeLayer} and a
 * {@link SelectionLayer}, where also an alternative tree layer implementation
 * can be used. It adds the key bindings that allows the space bar to be pressed
 * to expand/collapse tree nodes.
 */
public class TreeLayerExpandCollapseKeyBindings extends AbstractUiBindingConfiguration {

    protected final IUniqueIndexLayer treeLayer;
    protected final SelectionLayer selectionLayer;

    /**
     * @param treeLayer
     *            provides the necessary labels to detect tree nodes that can be
     *            expanded/collapsed.
     * @param selectionLayer
     *            the {@link SelectionLayer} - provides the selection anchor
     *            (the context for the action).
     * @since 1.6
     */
    public TreeLayerExpandCollapseKeyBindings(IUniqueIndexLayer treeLayer, SelectionLayer selectionLayer) {
        if (treeLayer == null) {
            throw new IllegalArgumentException("treeLayer must not be null."); //$NON-NLS-1$
        }
        if (selectionLayer == null) {
            throw new IllegalArgumentException("selectionLayer must not be null."); //$NON-NLS-1$
        }

        this.treeLayer = treeLayer;
        this.selectionLayer = selectionLayer;
    }

    @Override
    public void configureUiBindings(UiBindingRegistry uiBindingRegistry) {
        TreeExpandCollapseKeyAction action = new TreeExpandCollapseKeyAction(this.selectionLayer);
        uiBindingRegistry.registerFirstKeyBinding(anchorLabel(this.selectionLayer, this.treeLayer, TREE_EXPANDED_CONFIG_TYPE, new KeyEventMatcher(SWT.NONE, 32)), action);
        uiBindingRegistry.registerFirstKeyBinding(anchorLabel(this.selectionLayer, this.treeLayer, TREE_COLLAPSED_CONFIG_TYPE, new KeyEventMatcher(SWT.NONE, 32)), action);
    }

}