EPPlus/Style/ExcelFill.cs

/*******************************************************************************
 * You may amend and distribute as you like, but don't remove this header!
 *
 * EPPlus provides server-side generation of Excel 2007/2010 spreadsheets.
 * See http://www.codeplex.com/EPPlus for details.
 *
 * Copyright (C) 2011  Jan Källman
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.

 * This library 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 Lesser General Public License for more details.
 *
 * The GNU Lesser General Public License can be viewed at http://www.opensource.org/licenses/lgpl-license.php
 * If you unfamiliar with this license or have questions about it, here is an http://www.gnu.org/licenses/gpl-faq.html
 *
 * All code and executables are provided "as is" with no warranty either express or implied.
 * The author accepts no liability for any damage or loss of business that this product may cause.
 *
 * Code change notes:
 *
 * Author							Change						Date
 * ******************************************************************************
 * Jan Källman		                Initial Release		        2009-10-01
 * Jan Källman		License changed GPL-->LGPL 2011-12-16
 *******************************************************************************/

namespace OfficeOpenXml.Style;

/// <summary>
/// The background fill of a cell
/// </summary>
public class ExcelFill : StyleBase {
  internal ExcelFill(
      ExcelStyles styles,
      XmlHelper.ChangedEventHandler changedEvent,
      int positionId,
      string address,
      int index)
      : base(styles, changedEvent, positionId, address) {
    Index = index;
  }

  /// <summary>
  /// The pattern for solid fills.
  /// </summary>
  public ExcelFillStyle PatternType {
    get {
      if (Index == int.MinValue) {
        return ExcelFillStyle.None;
      }
      return _styles.Fills[Index].PatternType;
    }
  }

  private ExcelColor _patternColor;

  /// <summary>
  /// The color of the pattern
  /// </summary>
  public ExcelColor PatternColor {
    get {
      if (_patternColor == null) {
        _patternColor = new(
            _styles,
            _ChangedEvent,
            _positionID,
            _address,
            eStyleClass.FillPatternColor,
            this);
        if (_gradient != null) {
          _gradient = null;
        }
      }
      return _patternColor;
    }
  }

  private ExcelColor _backgroundColor;

  /// <summary>
  /// The background color
  /// </summary>
  public ExcelColor BackgroundColor {
    get {
      if (_backgroundColor == null) {
        _backgroundColor = new(
            _styles,
            _ChangedEvent,
            _positionID,
            _address,
            eStyleClass.FillBackgroundColor,
            this);
        if (_gradient != null) {
          _gradient = null;
        }
      }
      return _backgroundColor;
    }
  }

  private ExcelGradientFill _gradient;

  /// <summary>
  /// Access to properties for gradient fill.
  /// </summary>
  public ExcelGradientFill Gradient {
    get {
      if (_gradient == null) {
        _gradient = new(_styles, _ChangedEvent, _positionID, _address, Index);
        _backgroundColor = null;
        _patternColor = null;
      }
      return _gradient;
    }
  }

  internal override string Id {
    get {
      if (_gradient == null) {
        return PatternType + PatternColor.Id + BackgroundColor.Id;
      }
      return _gradient.Id;
    }
  }
}