从数据表动态更新LiveCharts

如何解决从数据表动态更新LiveCharts

我已经阅读文档好几天了，但是无论尝试如何，我都无法正常工作。我有“基本行图”，并希望显示为花费的图形时间。我的酒吧标题和价值在不断变化（添加了更多商品）。我可以使用当前代码添加栏，但无法为每个添加的栏添加标题。仅第一个标题/第一个标题标题可见，其他所有/即将出现的标题不可见。

如何以适当的方式添加标题和值？ （我已经熟悉文档https://lvcharts.net/App/examples/v1/wf/Basic%20Row）

这是我的代码（您可以从注释掉的部分中看到尝试过的内容）：

    public static SeriesCollection SeriesCollection { get; set; }
    public static string[] Labels { get; set; }
    public static List<string> LabelsList { get; set; }
    public static Func<double,string> Formatter { get; set; }

    public AppUsageBargraph()
    {
        InitializeComponent();

        LabelsList = new List<string>();

        SeriesCollection = new SeriesCollection
        {
            new RowSeries
            {
                Values = new ChartValues<double> { },DataLabels = true
            }
        };

        DataContext = this;
    }

    public static void UpdateChart()
    {
        SeriesCollection[0].Values.Clear();
        LabelsList.Clear();

        //Labels = MainProcess.activitylogGrouped.Rows.Cast<DaTarow>().Select(row => row["Window Title"].ToString()).ToArray();

        foreach (DaTarow row in MainProcess.activitylogGrouped.Rows)
        {
            SeriesCollection[0].Values.Add(Convert.Todouble(row["Time Spent"]));
            //SeriesCollection[0]. = row["Time Spent"].ToString());
            LabelsList.Add(row["Window Title"].ToString());
        }

        //MessageBox.Show(Labels[0].ToString());

        Labels = LabelsList.ToArray(); 


        //foreach (var item in Labels)
        //{
        //    MessageBox.Show(item);
        //}

        //Labels = new[]
        //        {
        //              "Shea Ferriera",//              "Maurita Powel",//              "Scottie brogdon",//              "Teresa Kerman",//              "Nell Venuti",//              "Anibal brothers",//              "Anderson Dillman"
        //           };

        //Formatter = value => value.ToString("N");
    }

解决方法

关键是使用ObservableCollection<string>而不是string[]。

我还建议使用模型来封装实际的图表数据点。因此，我引入了DataModel类。

以下示例显示如何将值和标签动态绑定到图表。我应该说，使所有内容public static都是一种很难闻的代码设计。

MainWindow.xaml

<Window>
  <Window.DataContext>
    <ViewModel />
  </Window.DataContext>

  <wpf:CartesianChart Height="500">
    <CartesianChart.Series>
      <RowSeries Values="{Binding ChartModel.RowSeries}"
                 Configuration="{Binding ChartModel.RowSeriesConfiguration}"/>
    </CartesianChart.Series>
    <CartesianChart.AxisY>
      <Axis Labels="{Binding ChartModel.RowSeriesLabels}" />
    </CartesianChart.AxisY>
  </CartesianChart>
</Window>

ViewModel.cs

public class ViewModel : INotifyPropertyChanged
{
  public ViewModel()
  {
    this.ChartModel = new ChartModel();
  }

  public void UpdateChart()
  {
    foreach (DataRow row in MainProcess.ActivityLogGrouped.Rows)
    {
      if (double.TryParse(row["Time Spent"],out double value)
      {
        string label = row["Window Title"];
        var newDataModel = new DataModel(value,label);

        this.ChartModel.RowSeries.Add(newDataModel);            
        this.ChartModel.RowSeriesLabels.Add(newDataModel.Label);
      }
    }
  }

  public ChartModel ChartModel { get; set; }

  public event PropertyChangedEventHandler PropertyChanged;
  protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
  {
    this.PropertyChanged?.Invoke(this,new PropertyChangedEventArgs(propertyName));
  }
}

ChartModel.cs

public class ChartModel : INotifyPropertyChanged
{
  public ChartModel()
  {
    // Initialize chart
    this.RowSeries = new ChartValues<DataModel>()
    {
      new DataModel(20,"Shea Ferriera"),new DataModel(100,"Maurita Powel"),new DataModel(60,"Scottie Brogdon"),};

    // Create labels
    this.RowSeriesLabels = new ObservableCollection<string>();
    foreach (DataModel dataModel in this.RowSeries)
    {
      this.RowSeriesLabels.Add("dataModel.Label");
    }

    // DatModel to value mapping
    this.RowSeriesConfiguration = new CartesianMapper<DataModel>()
      .X(dataModel => dataModel.Value);
  }

  public CartesianMapper<DataModel> RowSeriesConfiguration { get; set; }
  public ChartValues<DataModel> RowSeries { get; set; }
  public ObservableCollection<string> RowSeriesLabels { get; set; }

  public event PropertyChangedEventHandler PropertyChanged;
  protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
  {
    this.PropertyChanged?.Invoke(this,new PropertyChangedEventArgs(propertyName));
  }
}

DataModel.cs

public class DataModel
{
  public DataModel(double value,string label)
  {
    this.Value = value;
    this.Label = label;
  }

  public double Value { get; set; }
  public string Label { get; set; }
}