org.compiere.mfg_scm.eclipse.db.editors.ComboFieldEditor.java Source code

Java tutorial

Introduction

Here is the source code for org.compiere.mfg_scm.eclipse.db.editors.ComboFieldEditor.java

Source

/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.compiere.mfg_scm.eclipse.db.editors;

import org.eclipse.jface.preference.FieldEditor;
import org.eclipse.jface.util.Assert;
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.widgets.Combo;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;

/**
 * 
 * @author <a href="mailto:adl@compiere-mfgscm.org">Andre Charles Legendre </a>
 */

/**
 * A field editor for a combo box that allows the drop-down selection of one of
 * a list of items.
 * 
 * XXX: Note this is a copy from org.eclipse.debug.internal.ui.preferences This
 * class can be removed once bug 24928 is fixed.
 * 
 * @since 2.1
 */
public class ComboFieldEditor extends FieldEditor {

    /**
     * The <code>Combo</code> widget.
     */
    private Combo fCombo;

    /**
     * The value (not the name) of the currently selected item in the Combo
     * widget.
     */
    private String fValue;

    /**
     * The names (labels) and underlying values to populate the combo widget.
     * These should be arranged as: { {name1, value1}, {name2, value2}, ...}
     */
    private String[][] fEntryNamesAndValues;

    public ComboFieldEditor(String name, String labelText, String[][] entryNamesAndValues, Composite parent) {
        init(name, labelText);
        Assert.isTrue(checkArray(entryNamesAndValues));
        fEntryNamesAndValues = entryNamesAndValues;
        createControl(parent);
    }

    /**
     * Checks whether given <code>String[][]</code> is of "type"
     * <code>String[][2]</code>.
     * 
     * @return <code>true</code> if it is ok, and <code>false</code>
     *         otherwise
     */
    private boolean checkArray(String[][] table) {
        if (table == null) {
            return false;
        }
        for (int i = 0; i < table.length; i++) {
            String[] array = table[i];
            if (array == null || array.length != 2) {
                return false;
            }
        }
        return true;
    }

    /*
     * @see FieldEditor#adjustForNumColumns(int)
     */
    protected void adjustForNumColumns(int numColumns) {
        Control control = getLabelControl();
        if (control != null) {
            ((GridData) control.getLayoutData()).horizontalSpan = numColumns;
        }
        ((GridData) fCombo.getLayoutData()).horizontalSpan = numColumns;
    }

    /*
     * @see FieldEditor#doFillIntoGrid(Composite, int)
     */
    protected void doFillIntoGrid(Composite parent, int numColumns) {
        Control control = getLabelControl(parent);
        GridData gd = new GridData();
        gd.horizontalSpan = numColumns;
        control.setLayoutData(gd);
        control = getComboBoxControl(parent);
        gd = new GridData();
        gd.horizontalSpan = numColumns;
        control.setLayoutData(gd);
    }

    /*
     * @see FieldEditor#doLoad()
     */
    protected void doLoad() {
        updateComboForValue(getPreferenceStore().getString(getPreferenceName()));
    }

    /*
     * @see FieldEditor#doLoadDefault()
     */
    protected void doLoadDefault() {
        updateComboForValue(getPreferenceStore().getDefaultString(getPreferenceName()));
    }

    /*
     * @see FieldEditor#doStore()
     */
    protected void doStore() {
        if (fValue == null) {
            getPreferenceStore().setToDefault(getPreferenceName());
            return;
        }

        getPreferenceStore().setValue(getPreferenceName(), fValue);
    }

    /*
     * @see FieldEditor#getNumberOfControls()
     */
    public int getNumberOfControls() {
        return 2;
    }

    /**
     * Lazily create and return the Combo control.
     */
    public Combo getComboBoxControl(Composite parent) {
        if (fCombo == null) {
            fCombo = new Combo(parent, SWT.READ_ONLY);
            for (int i = 0; i < fEntryNamesAndValues.length; i++) {
                fCombo.add(fEntryNamesAndValues[i][0], i);
            }
            fCombo.setFont(parent.getFont());
            fCombo.addSelectionListener(new SelectionAdapter() {
                public void widgetSelected(SelectionEvent evt) {
                    String oldValue = fValue;
                    String name = fCombo.getText();
                    fValue = getValueForName(name);
                    setPresentsDefaultValue(false);
                    fireValueChanged(VALUE, oldValue, fValue);
                }
            });
        }
        return fCombo;
    }

    /**
     * Given the name (label) of an entry, return the corresponding value.
     */
    protected String getValueForName(String name) {
        for (int i = 0; i < fEntryNamesAndValues.length; i++) {
            String[] entry = fEntryNamesAndValues[i];
            if (name.equals(entry[0])) {
                return entry[1];
            }
        }
        return fEntryNamesAndValues[0][0];
    }

    /**
     * Set the name in the combo widget to match the specified value.
     */
    protected void updateComboForValue(String value) {
        fValue = value;
        for (int i = 0; i < fEntryNamesAndValues.length; i++) {
            if (value.equals(fEntryNamesAndValues[i][1])) {
                fCombo.setText(fEntryNamesAndValues[i][0]);
                return;
            }
        }
        if (fEntryNamesAndValues.length > 0) {
            fValue = fEntryNamesAndValues[0][1];
            fCombo.setText(fEntryNamesAndValues[0][0]);
        }
    }
}