es.cv.gvcase.fefem.common.composites.EMFPropertyEReferenceComposite.java Source code

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Here is the source code for es.cv.gvcase.fefem.common.composites.EMFPropertyEReferenceComposite.java

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/***************************************************************************
* Copyright (c) 2008 Conselleria de Infraestructuras y Transporte,
* Generalitat de la Comunitat Valenciana . 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: Mario Cervera Ubeda (Integranova)
*
**************************************************************************/
package es.cv.gvcase.fefem.common.composites;

import org.eclipse.core.databinding.UpdateValueStrategy;
import org.eclipse.core.databinding.conversion.Converter;
import org.eclipse.core.databinding.conversion.IConverter;
import org.eclipse.core.databinding.observable.value.IObservableValue;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.jface.databinding.swt.SWTObservables;
import org.eclipse.jface.viewers.ILabelProvider;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.forms.widgets.FormToolkit;

import es.cv.gvcase.fefem.common.FEFEMPage;
import es.cv.gvcase.fefem.common.providers.EObjectLabelProvider;
import es.cv.gvcase.fefem.common.widgets.CSingleObjectChooser;

/**
 * An implementation of a composite with a chooser.
 * Invoke bindFeatureToWidget to bind the chooser with the feature
 * 
 * @author Mario Cervera
 */
public abstract class EMFPropertyEReferenceComposite extends EMFPropertyComposite {

    /**
     * The combo box control for the section.
     */
    private CSingleObjectChooser chooser;

    public EMFPropertyEReferenceComposite(Composite parent, int style, FormToolkit toolkit, EObject eObject,
            FEFEMPage page) {
        super(parent, style, toolkit, eObject, page);

        hookListeners();
    }

    public EMFPropertyEReferenceComposite(Composite parent, int style, FormToolkit toolkit, Viewer viewer,
            FEFEMPage page) {
        super(parent, style, toolkit, viewer, page);

        hookListeners();
    }

    protected CSingleObjectChooser getChooser() {
        return chooser;
    }

    public void setLabelProvider(ILabelProvider lp) {
        chooser.setLabelProvider(lp);
    }

    public void setChoices(Object[] choices) {
        chooser.setChoices(choices);
    }

    protected void createWidgets(FormToolkit toolkit) {

        this.setLayout(new GridLayout(2, false));

        createLabel(toolkit);

        chooser = new CSingleObjectChooser(this, toolkit, SWT.NONE);
        chooser.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
        chooser.setLabelProvider(getLabelProvider());
        IStructuredContentProvider provider = this.getChooserContentProvider();
        if (provider != null) {
            chooser.setStructuredContentProvider(provider);
        } else {
            setChoices(getChoices());
        }

        if (getFeature() != null) {
            chooser.setChangeable(getFeature().isChangeable() && this.isEditable());
        }
    }

    private IStructuredContentProvider getChooserContentProvider() {
        return new IStructuredContentProvider() {

            public Object[] getElements(Object inputElement) {
                Object[] choices = getChoices();
                for (int i = 0; i < choices.length; i++) {
                    if (choices[i] == null) {
                        choices[i] = "";
                    }
                }
                return choices;
            }

            public void dispose() {
            }

            public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
            }

        };
    }

    protected void hookListeners() {
        chooser.addSelectionListener(new SelectionAdapter() {
            public void widgetSelected(SelectionEvent e) {
                handleComboModified();
            }
        });
    }

    /**
     * Handle the combo modified event.
     */
    protected void handleComboModified() {
        if (modelObservable != null) {
            modelObservable.setValue(chooser.getSelection());
        }

        getPage().setDirty(true);
    }

    /**
     * A converter is needed to convert the String of the Text field
     * of the chooser into a model element
     * 
     * @return the converter
     */
    protected IConverter getConverter() {

        return new ChooserConverter(null, null);
    }

    @Override
    protected UpdateValueStrategy getModelToTargetUpdateValueStrategy() {
        UpdateValueStrategy uvs = new UpdateValueStrategy();
        if (getConverter() != null) {
            uvs.setConverter(getConverter());
        }
        return uvs;
    }

    @Override
    protected IObservableValue getTargetObservable() {
        return SWTObservables.observeText(chooser.getText(), SWT.Modify);
    }

    private class ChooserConverter extends Converter {

        public ChooserConverter(Object fromType, Object toType) {
            super(fromType, toType);
        }

        public Object convert(Object fromObject) {

            if (fromObject instanceof EObject) {
                return getLabelProvider().getText(fromObject);
            }

            return null;
        }
    }

    protected ILabelProvider getLabelProvider() {
        return new EObjectLabelProvider();
    }

    protected abstract Object[] getChoices();

    @Override
    protected void handleSelectionChanged() {
        if (this.isDisposed())
            return;
        this.setChoices(getChoices());
        if (getChooser() != null && this.getFeatureValue() != null) {
            getChooser().setSelection(this.getFeatureValue());
        }
    }
}