org.soyatec.tooling.gef.properties.SpinnerFieldEditor.java Source code

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Here is the source code for org.soyatec.tooling.gef.properties.SpinnerFieldEditor.java

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/*******************************************************************************
 * Copyright (c) 2015 Soyatec and others.
 * 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:
 *    Soyatec - initial API and implementation
 *******************************************************************************/
package org.soyatec.tooling.gef.properties;

import org.eclipse.jface.preference.FieldEditor;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Spinner;

/**
 * FieldEditor for integer values.
 * 
 * @author Ecsoya
 */
public class SpinnerFieldEditor extends FieldEditor {

    /**
     * Value that will feed Spinner.setIncrement(int).
     */
    private int incrementValue;

    /**
     * Value that will feed Spinner.setMaximum(int).
     */
    private int maxValue;

    /**
     * Value that will feed Spinner.setMinimum(int).
     */
    private int minValue;

    /**
     * Old integer value.
     */
    private int oldValue;

    /**
     * Value that will feed Spinner.setPageIncrement(int).
     */
    private int pageIncrementValue;

    /**
     * The scale, or <code>null</code> if none.
     */
    protected Spinner spinner;

    /**
     * Creates a scale field editor.
     * 
     * @param name
     *            the name of the preference this field editor works on
     * @param labelText
     *            the label text of the field editor
     * @param parent
     *            the parent of the field editor's control
     */
    public SpinnerFieldEditor(final String name, final String labelText, final Composite parent) {
        super(name, labelText, parent);
        setDefaultValues();
    }

    /**
     * Creates a scale field editor with particular scale values.
     * 
     * @param name
     *            the name of the preference this field editor works on
     * @param labelText
     *            the label text of the field editor
     * @param parent
     *            the parent of the field editor's control
     * @param min
     *            the value used for Scale.setMinimum(int).
     * @param max
     *            the value used for Scale.setMaximum(int).
     * @param increment
     *            the value used for Scale.setIncrement(int).
     * @param pageIncrement
     *            the value used for Scale.setPageIncrement(int).
     */
    public SpinnerFieldEditor(final String name, final String labelText, final Composite parent, final int min,
            final int max, final int increment, final int pageIncrement) {
        super(name, labelText, parent);
        setValues(min, max, increment, pageIncrement);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.preference.FieldEditor#adjustForNumColumns(int)
     */
    @Override
    protected void adjustForNumColumns(final int numColumns) {
        ((GridData) spinner.getLayoutData()).horizontalSpan = numColumns - 1;
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.eclipse.jface.preference.FieldEditor#doFillIntoGrid(org.eclipse.swt
     * .widgets.Composite, int)
     */
    @Override
    protected void doFillIntoGrid(final Composite parent, final int numColumns) {
        final Control control = getLabelControl(parent);
        GridData gd = new GridData();
        control.setLayoutData(gd);

        spinner = getSpinnerControl(parent);
        gd = new GridData(GridData.FILL_HORIZONTAL);
        gd.verticalAlignment = GridData.FILL;
        gd.horizontalSpan = numColumns - 1;
        gd.grabExcessHorizontalSpace = true;
        spinner.setLayoutData(gd);
        updateSpinner();
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.preference.FieldEditor#doLoad()
     */
    @Override
    protected void doLoad() {
        if (spinner != null) {
            final int value = getPreferenceStore().getInt(getPreferenceName());
            spinner.setSelection(value);
            oldValue = value;
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.preference.FieldEditor#doLoadDefault()
     */
    @Override
    protected void doLoadDefault() {
        if (spinner != null) {
            final int value = getPreferenceStore().getDefaultInt(getPreferenceName());
            spinner.setSelection(value);
        }
        valueChanged();
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.preference.FieldEditor#doStore()
     */
    @Override
    protected void doStore() {
        getPreferenceStore().setValue(getPreferenceName(), spinner.getSelection());
    }

    /**
     * Returns the value that will be used for Scale.setIncrement(int).
     * 
     * @return the value.
     * @see org.eclipse.swt.widgets.Scale#setIncrement(int)
     */
    public int getIncrement() {
        return incrementValue;
    }

    /**
     * Returns the value that will be used for Scale.setMaximum(int).
     * 
     * @return the value.
     * @see org.eclipse.swt.widgets.Scale#setMaximum(int)
     */
    public int getMaximum() {
        return maxValue;
    }

    /**
     * Returns the value that will be used for Scale.setMinimum(int).
     * 
     * @return the value.
     * @see org.eclipse.swt.widgets.Scale#setMinimum(int)
     */
    public int getMinimum() {
        return minValue;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.preference.FieldEditor#getNumberOfControls()
     */
    @Override
    public int getNumberOfControls() {
        return 2;
    }

    /**
     * Returns the value that will be used for Scale.setPageIncrement(int).
     * 
     * @return the value.
     * @see org.eclipse.swt.widgets.Scale#setPageIncrement(int)
     */
    public int getPageIncrement() {
        return pageIncrementValue;
    }

    /**
     * Returns this field editor's scale control.
     * 
     * @return the scale control, or <code>null</code> if no scale field is
     *         created yet
     */
    public Spinner getSpinnerControl() {
        return spinner;
    }

    /**
     * Returns this field editor's scale control. The control is created if it
     * does not yet exist.
     * 
     * @param parent
     *            the parent
     * @return the scale control
     */
    private Spinner getSpinnerControl(final Composite parent) {
        if (spinner == null) {
            spinner = new Spinner(parent, SWT.READ_ONLY | SWT.BORDER);
            spinner.setFont(parent.getFont());
            spinner.addSelectionListener(new SelectionAdapter() {
                public void widgetSelected(final SelectionEvent event) {
                    valueChanged();
                }
            });
            spinner.addDisposeListener(new DisposeListener() {
                public void widgetDisposed(final DisposeEvent event) {
                    spinner = null;
                }
            });
        } else {
            checkParent(spinner, parent);
        }
        return spinner;
    }

    /**
     * Set default values for the various scale fields. These defaults are:<br>
     * <ul>
     * <li>Minimum = 0
     * <li>Maximim = 10
     * <li>Increment = 1
     * <li>Page Increment = 1
     * </ul>
     */
    private void setDefaultValues() {
        setValues(0, 10, 1, 1);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.jface.preference.FieldEditor#setFocus()
     */
    @Override
    public void setFocus() {
        if (spinner != null && !spinner.isDisposed()) {
            spinner.setFocus();
        }
    }

    /**
     * Set the value to be used for Scale.setIncrement(int) and update the
     * scale.
     * 
     * @param increment
     *            a value greater than 0.
     * @see org.eclipse.swt.widgets.Scale#setIncrement(int)
     */
    public void setIncrement(final int increment) {
        this.incrementValue = increment;
        updateSpinner();
    }

    /**
     * Set the value to be used for Scale.setMaximum(int) and update the scale.
     * 
     * @param max
     *            a value greater than 0.
     * @see org.eclipse.swt.widgets.Scale#setMaximum(int)
     */
    public void setMaximum(final int max) {
        this.maxValue = max;
        updateSpinner();
    }

    /**
     * Set the value to be used for Scale.setMinumum(int) and update the scale.
     * 
     * @param min
     *            a value greater than 0.
     * @see org.eclipse.swt.widgets.Scale#setMinimum(int)
     */
    public void setMinimum(final int min) {
        this.minValue = min;
        updateSpinner();
    }

    /**
     * Set the value to be used for Scale.setPageIncrement(int) and update the
     * scale.
     * 
     * @param pageIncrement
     *            a value greater than 0.
     * @see org.eclipse.swt.widgets.Scale#setPageIncrement(int)
     */
    public void setPageIncrement(final int pageIncrement) {
        this.pageIncrementValue = pageIncrement;
        updateSpinner();
    }

    /**
     * Set all Scale values.
     * 
     * @param min
     *            the value used for Scale.setMinimum(int).
     * @param max
     *            the value used for Scale.setMaximum(int).
     * @param increment
     *            the value used for Scale.setIncrement(int).
     * @param pageIncrement
     *            the value used for Scale.setPageIncrement(int).
     */
    private void setValues(final int min, final int max, final int increment, final int pageIncrement) {
        this.incrementValue = increment;
        this.maxValue = max;
        this.minValue = min;
        this.pageIncrementValue = pageIncrement;
        updateSpinner();
    }

    /**
     * Update the scale particulars with set values.
     */
    private void updateSpinner() {
        if (spinner != null && !spinner.isDisposed()) {
            spinner.setMinimum(getMinimum());
            spinner.setMaximum(getMaximum());
            spinner.setIncrement(getIncrement());
            spinner.setPageIncrement(getPageIncrement());
        }
    }

    /**
     * Informs this field editor's listener, if it has one, about a change to
     * the value (<code>VALUE</code> property) provided that the old and new
     * values are different.
     * <p>
     * This hook is <em>not</em> called when the scale is initialized (or reset
     * to the default value) from the preference store.
     * </p>
     */
    protected void valueChanged() {
        setPresentsDefaultValue(false);

        final int newValue = spinner.getSelection();
        if (newValue != oldValue) {
            fireStateChanged(IS_VALID, false, true);
            fireValueChanged(VALUE, new Integer(oldValue), new Integer(newValue));
            oldValue = newValue;
        }
    }

    public void setEnabled(final boolean enabled, final Composite parent) {
        super.setEnabled(enabled, parent);
        getSpinnerControl(parent).setEnabled(enabled);
    }
}