从数据表动态更新LiveCharts

Question

我已经阅读文档好几天了，但无论我做什么，我都无法让它发挥作用。我有"基本行"图表，希望以图表形式显示所花费的时间。我的栏标题和值不断变化(添加了更多项目(。我可以用我当前的代码添加栏，但不能为每个添加的栏添加标题。只有第一个标题/第一个栏标题可见，所有其他标题/即将出现的标题都不可见。

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

这是我的代码(你可以从评论部分看到已经尝试过的内容(：

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");
}

Answer 1

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。为此，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，制作所有public static是一个非常糟糕的代码设计。

主窗口.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));
}
}

图表模型.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; }
}