ecommons.waltable/org.eclipse.statet.ecommons.waltable.core/src/org/eclipse/statet/ecommons/waltable/edit/editor/DateCellEditor.java

/*=============================================================================#
 # Copyright (c) 2013, 2021 Dirk Fauth and others.
 # 
 # This program and the accompanying materials are made available under the
 # terms of the Eclipse Public License 2.0 which is available at
 # https://www.eclipse.org/legal/epl-2.0.
 # 
 # SPDX-License-Identifier: EPL-2.0
 # 
 # Contributors:
 #     Dirk Fauth <dirk.fauth@gmail.com> - initial API and implementation
 #=============================================================================*/ 

package org.eclipse.statet.ecommons.waltable.edit.editor;

import java.util.Calendar;
import java.util.Date;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.KeyAdapter;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.DateTime;

import org.eclipse.statet.ecommons.waltable.coordinate.Direction;
import org.eclipse.statet.ecommons.waltable.edit.EditMode;
import org.eclipse.statet.ecommons.waltable.style.CellStyleAttributes;


/**
 * ICellEditor implementation that uses a DateTime control for editing.
 * It supports objects of type Date and Calendar aswell.
 * <p>
 * Introduces the contract that the editor control value is of type Calendar.
 * Therefore the methods to deal with the canonical values need to be overriden
 * too, to avoid conversion of the canonical value to display value by using
 * the IDisplayConverter that is registered together with this editor.
 * <p>
 * Note: This is an example implementation for a Date editor. As the SWT DateTime
 * 		 control has some serious issues like it is not nullable, has issues on
 * 		 setting the focus programmatically and it is not possible to open the
 * 		 dropdown programmatically, we suggest to rather use some Nebula widget
 * 		 or a custom widget for date editing.
 */
public class DateCellEditor extends AbstractCellEditor {

	/**
	 * The DateTime control which is the editor wrapped by this DateCellEditor.
	 */
	private DateTime dateTime;
	
	/**
	 * Flag to configure whether the selection should move after a value was
	 * committed after pressing enter.
	 */
	private final boolean moveSelectionOnEnter;
	
	/**
	 * Creates the default DateCellEditor that does not move the selection on committing
	 * the value by pressing enter.
	 */
	public DateCellEditor() {
		this(false);
	}
	
	/**
	 * Creates a DateCellEditor.
	 * @param moveSelectionOnEnter Flag to configure whether the selection should move after a value was
	 * 			committed after pressing enter.
	 */
	public DateCellEditor(final boolean moveSelectionOnEnter) {
		this.moveSelectionOnEnter= moveSelectionOnEnter;
	}

	@Override
	public Object getEditorValue() {
		final Calendar cal= Calendar.getInstance();
		cal.set(
				this.dateTime.getYear(), 
				this.dateTime.getMonth(), 
				this.dateTime.getDay());
		return cal;
	}

	@Override
	public void setEditorValue(final Object value) {
		//in setCanonicalValue() we ensure that the value is of type Calendar
		//but an additional check to ensure type safety doesn't hurt
		if (value instanceof Calendar) {
			final Calendar cal= (Calendar)value;
			this.dateTime.setDate(
					cal.get(Calendar.YEAR), 
					cal.get(Calendar.MONTH), 
					cal.get(Calendar.DATE));
		}
	}

	@Override
	public Object getCanonicalValue() {
		if (this.layerCell.getDataValue(0, null) instanceof Calendar) {
			return getEditorValue();
		}
		else if (this.layerCell.getDataValue(0, null) instanceof Date) {
			return ((Calendar)getEditorValue()).getTime();
		}
		return null;
	}
	
	@Override
	public void setCanonicalValue(final Object canonicalValue) {
		Calendar editorValue= null;
		if (canonicalValue instanceof Calendar) {
			editorValue= (Calendar) canonicalValue;
		}
		else if (canonicalValue instanceof Date) {
			editorValue= Calendar.getInstance();
			editorValue.setTime((Date)canonicalValue);
		}
		
		if (editorValue != null) {
			setEditorValue(editorValue);
		}
	}

	@Override
	public DateTime getEditorControl() {
		return this.dateTime;
	}

	@Override
	public DateTime createEditorControl(final Composite parent) {
		final DateTime dateControl= new DateTime(parent, SWT.DATE | SWT.DROP_DOWN);
		
		//set style information configured in the associated cell style
		dateControl.setBackground(this.cellStyle.getAttributeValue(CellStyleAttributes.BACKGROUND_COLOR));
		dateControl.setForeground(this.cellStyle.getAttributeValue(CellStyleAttributes.FOREGROUND_COLOR));
		dateControl.setFont(this.cellStyle.getAttributeValue(CellStyleAttributes.FONT));
		
		//add a key listener that will commit or close the editor for special key strokes
		dateControl.addKeyListener(new KeyAdapter() {

			@Override
			public void keyPressed(final KeyEvent event) {
				if (event.keyCode == SWT.CR || event.keyCode == SWT.KEYPAD_CR) {
					
					final boolean commit= (event.stateMask == SWT.ALT) ? false : true;
					Direction move= null;
					if (DateCellEditor.this.moveSelectionOnEnter && DateCellEditor.this.editMode == EditMode.INLINE) {
						if (event.stateMask == 0) {
							move= Direction.DOWN;
						} else if (event.stateMask == SWT.SHIFT) {
							move= Direction.UP;
						}
					}
					
					if (commit) {
						commit(move);
					}
					
					if (DateCellEditor.this.editMode == EditMode.DIALOG) {
						parent.forceFocus();
					}
				} 
				else if (event.keyCode == SWT.ESC && event.stateMask == 0){
					close();
				}
			}
		});
		
		return dateControl;
	}

	@Override
	protected Control activateCell(final Composite parent, final Object originalCanonicalValue) {
		this.dateTime= createEditorControl(parent);
		setCanonicalValue(originalCanonicalValue);
		
		//this is necessary so the control gets the focus
		//but this also causing some issues as focusing the DateTime control
		//programmatically does some strange things with showing the editable data
		//also it seems to be not possible to open the dropdown programmatically
		this.dateTime.forceFocus();
		
		return this.dateTime;
	}

}