Application: gvSIG desktop » Library: org.gvsig.tools

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 * 

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 * 

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 

 * MA  02110-1301, USA.

 * 

 */

/*

 * AUTHORS (In addition to CIT):

 * 2010 Institute of New Imaging Technologies (INIT): 

 *   http://www.init.uji.es

 * Geographic Information research group: 

 *   http://www.geoinfo.uji.es

 * Universitat Jaume I, Spain

 */

/**

 * 

 */

package org.gvsig.tools.swing.spi;

import java.util.ArrayList;

import java.util.List;

import org.gvsig.tools.dynobject.DynField;

import org.gvsig.tools.dynobject.DynObject;

import org.gvsig.tools.swing.api.dynobject.ValueChangedListener;

import org.gvsig.tools.swing.api.dynobject.dynfield.JDynFieldComponent;

import org.gvsig.tools.swing.api.dynobject.dynfield.ValueField;

/**

 * 

 * This interfaces provides with the logic necessary to create

 * JDynFieldComponents. First,

 * the initial values are extracted. Second, the user interface components are

 * created.

 * Third, the initial value is set to the right component, and last but not

 * least, a

 * fireEventChanged event is raised to inform all Listeners that the value has

 * changed.

 * Some additional functions related to DynField attributes are also

 * implemented.

 * 

 * @author 2010 - <a href="cordinyana@gvsig.org">C?sar Ordi?ana</a> - gvSIG Team

 * @author 2010 - <a href="mailto:reinhold@uji.es">Cristian Mart?n&nbsp;</a> -

 *         gvSIG Team

 * @version $Id$

 * 

 */

public abstract class AbstractJDynField {

    private ValueField parent;

    protected final List<ValueChangedListener> listeners;

    public AbstractJDynField(ValueField parent) {

        this.parent = parent;

        listeners = new ArrayList<ValueChangedListener>();

    }

    /*

     * (non-Javadoc)

     * 

     * @seeorg.gvsig.tools.swing.api.dynobject.dynfield.JDynFieldComponent#

     * addValueChangedListener

     * (org.gvsig.tools.swing.api.dynobject.ValueChangedListener)

     */

    public void addValueChangedListener(ValueChangedListener listener) {

        // If it was the first item, we need to

        // initialize Component listeners

        // add listener to the dynfield set of listeners

        listeners.add(listener);

        // set supplementary listeners.

        this.setJDynFieldComponentListeners();

    }

    /**

     * The {@link JDynFieldComponent} can use this function to add any code

     * necessary

     * once all swing components have been initialized.

     */

    protected abstract void afterUI();

    /**

     * Then all {@link ValueChangedListener}s are fired to alert them

     * to check if the value has changed via the {@link getValue()} function of

     * the {@link JDynFieldComponent}.

     */

    public abstract void fireValueChangedEvent();

    /**

     * Gets the default value of the {@link ValueField} object.

     * 

     * @return

     *         the default value of the {@link ValueField} object.

     */

    public Object getDefaultFieldValue() {

        return this.getValueField().getDefaultFieldValue();

    }

    /**

     * Returns the {@link DynField} being rendered.

     * 

     * @return the {@link DynField}

     */

    public DynField getDynField() {

        return getValueField().getDynField();

    }

    /**

     * Gets the current value of the {@link ValueField} object.

     * 

     * @return

     *         the current value of the {@link ValueField} object.

     */

    public Object getFieldValue() {

        return this.getValueField().getFieldValue();

    }

    /**

     * Checks if the {@link ValueField} has an inputed value; if not, then it

     * asks

     * for its default value.

     * 

     * @return

     *         the initial value of the {@link ValueField}. It can be

     *         <b>null</b>.

     */

    public Object getInitialValue() {

        Object value = getFieldValue();

        if (value == null) {

            value = getDefaultFieldValue();

        }

        return value;

    }

    /**

     * Gets the {@link ValueField} object.

     * 

     * @return

     *         the {@link ValueField} object.

     */

    private ValueField getValueField() {

        return this.parent;

    }

    /**

     * Inits the JDynFieldComponent logic to create its components and check its

     * values.

     */

    protected void init() {

        this.initData();

        this.initUI();

        if (this.getDynField().isReadOnly()) {

            this.setReadOnly();

        }

        this.setValue(getInitialValue());

        this.afterUI();

    }

    /**

     * JDynFieldComponents can use this function to initialize any

     * data containers before the swing components are created.

     */

    protected abstract void initData();

    /**

     * {@link JDynFieldComponent}s can use this function to initialized any

     * swing components to be used afterwards, and specify their

     * default settings.

     */

    protected abstract void initUI();

    /**

     * Sets the current value of the {@link JDynFieldComponent} to the

     * {@link DynObject} value via the {@link ValueField} object.

     * 

     */

    public void setFieldValue(Object value) {

        this.getValueField().setFieldValue(value);

    }

    protected abstract void setJDynFieldComponentListeners();

    /**

     * The {@link JDynFieldComponent} can use this function to set a <b>non

     * null</b> value

     * into the correspondent swing component.

     * 

     * @param value

     *            the value to be set into the swing component.

     */

    protected abstract void setNonNullValue(Object value);

    /**

     * The {@link JDynFieldComponent} can use this function to set a <b>null</b>

     * value

     * into the correspondent swing component.

     * 

     * @param value

     *            the value to be set into the swing component.

     */

    protected abstract void setNullValue();

    /**

     * The {@link JDynFieldComponent} can implement this function to set the

     * swing

     * components that represent this {@link DynField} to readOnly mode.

     */

    protected abstract void setReadOnly();

    /**

     * Sets the value to the {@link JDynFieldComponent}. With this logic, it

     * checks first

     * if it is a null value or not. Then all {@link ValueChangedListener}s are

     * fired

     * to alert them to check if the value has changed via the {@link

     * getValue()} function.

     * 

     * @param value

     *            the value to be set into the swing component.

     */

    public void setValue(Object value) {

        if (value == null) {

            setNullValue();

        } else {

            setNonNullValue(value);

        }

        this.fireValueChangedEvent();

    }

}