source: branches/HeuristicLab.Problems.GrammaticalOptimization/DynamicDataDisplay/Charts/Axes/Numeric/ExponentialLabelProvider.cs @ 13398

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Globalization;
using System.Diagnostics;
using Microsoft.Research.DynamicDataDisplay.Charts.Axes;

namespace Microsoft.Research.DynamicDataDisplay.Charts
{
  /// <summary>
  /// Represents an axis label provider for double ticks, generating labels with numbers in exponential form when it is appropriate.
  /// </summary>
  public sealed class ExponentialLabelProvider : NumericLabelProviderBase
  {
    /// <summary>
    /// Initializes a new instance of the <see cref="ExponentialLabelProvider"/> class.
    /// </summary>
    public ExponentialLabelProvider() { }

    /// <summary>
    /// Creates labels by given ticks info.
    /// Is not intended to be called from your code.
    /// </summary>
    /// <param name="ticksInfo">The ticks info.</param>
    /// <returns>
    /// Array of <see cref="UIElement"/>s, which are axis labels for specified axis ticks.
    /// </returns>
    public override UIElement[] CreateLabels(ITicksInfo<double> ticksInfo)
    {
      var ticks = ticksInfo.Ticks;

      Init(ticks);

      UIElement[] res = new UIElement[ticks.Length];

      LabelTickInfo<double> tickInfo = new LabelTickInfo<double> { Info = ticksInfo.Info };

      for (int i = 0; i < res.Length; i++)
      {
        var tick = ticks[i];
        tickInfo.Tick = tick;
        tickInfo.Index = i;

        string labelText = GetString(tickInfo);

        TextBlock label;
        if (labelText.Contains('E'))
        {
          string[] substrs = labelText.Split('E');
          string mantissa = substrs[0];
          string exponenta = substrs[1];
          exponenta = exponenta.TrimStart('+');
          Span span = new Span();
          span.Inlines.Add(String.Format(CultureInfo.CurrentCulture, "{0}·10", mantissa));
          Span exponentaSpan = new Span(new Run(exponenta));
          exponentaSpan.BaselineAlignment = BaselineAlignment.Superscript;
          exponentaSpan.FontSize = 8;
          span.Inlines.Add(exponentaSpan);

          label = new TextBlock(span);
          LabelProviderProperties.SetExponentialIsCommonLabel(label, false);
        }
        else
        {
          label = (TextBlock)GetResourceFromPool();
          if (label == null)
          {
            label = new TextBlock();
          }

          label.Text = labelText;
        }
        res[i] = label;
        label.ToolTip = tick.ToString(CultureInfo.CurrentCulture);

        ApplyCustomView(tickInfo, label);
      }

      return res;
    }

    protected override bool ReleaseCore(UIElement label)
    {
      bool isNotExponential = LabelProviderProperties.GetExponentialIsCommonLabel(label);
      return isNotExponential && CustomView == null;
    }
  }
}