DecoratedGridCellValueAdaptor.java

/*
 * Copyright 2012 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.kie.workbench.common.widgets.decoratedgrid.client.widget;

import com.google.gwt.cell.client.AbstractCell;
import com.google.gwt.cell.client.ValueUpdater;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.event.shared.EventBus;
import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
import org.kie.workbench.common.widgets.decoratedgrid.client.widget.events.UpdateSelectedCellsEvent;

import java.util.Set;

/**
 * A Cell that casts values to whatever is appropriate for the wrapped Cell
 * @param <T> The data-type required by the wrapped cell
 */
public class DecoratedGridCellValueAdaptor<T extends Comparable<T>> extends AbstractCell<CellValue<? extends Comparable<?>>> {

    // Really we want AbstractCell<?> but that leads to generics hell
    private AbstractCell<T> cell;

    private EventBus eventBus;

    /**
     * @param cell
     */
    public DecoratedGridCellValueAdaptor( AbstractCell<T> cell,
                                          EventBus eventBus ) {
        super( cell.getConsumedEvents() );
        this.eventBus = eventBus;
        this.cell = cell;
    }

    @Override
    public boolean dependsOnSelection() {
        return cell.dependsOnSelection();
    }

    @Override
    public Set<String> getConsumedEvents() {
        return cell.getConsumedEvents();
    }

    @Override
    public boolean handlesSelection() {
        return cell.handlesSelection();
    }

    @Override
    @SuppressWarnings("unchecked")
    public boolean isEditing( Context context,
                              Element parent,
                              CellValue<? extends Comparable<?>> value ) {
        return cell.isEditing( context,
                               parent,
                               (T) value.getValue() );
    }

    @Override
    @SuppressWarnings("unchecked")
    public void onBrowserEvent( Context context,
                                Element parent,
                                CellValue<? extends Comparable<?>> value,
                                NativeEvent event,
                                ValueUpdater<CellValue<? extends Comparable<?>>> valueUpdater ) {

        // Updates are passed back to the DecoratedGridWidget where merged cells
        // are also updated. Override the Column's FieldUpdater because
        // a Horizontal MergableGridWidget will potentially have a different
        // data-type per row.
        cell.onBrowserEvent( context,
                             parent,
                             (T) value.getValue(),
                             event,
                             new ValueUpdater<T>() {

                                 public void update( T value ) {
                                     eventBus.fireEvent( new UpdateSelectedCellsEvent( value ) );
                                 }

                             } );
    }

    @Override
    @SuppressWarnings("unchecked")
    public void render( Context context,
                        CellValue<? extends Comparable<?>> value,
                        SafeHtmlBuilder sb ) {
        cell.render( context,
                     (T) value.getValue(),
                     sb );
    }

    @Override
    @SuppressWarnings("unchecked")
    public boolean resetFocus( Context context,
                               Element parent,
                               CellValue<? extends Comparable<?>> value ) {
        return cell.resetFocus( context,
                                parent,
                                (T) value.getValue() );
    }

    @Override
    @SuppressWarnings("unchecked")
    public void setValue( Context context,
                          Element parent,
                          CellValue<? extends Comparable<?>> value ) {
        cell.setValue( context,
                       parent,
                       (T) value.getValue() );
    }

}