具有LiveCharts的WPF在运行时添加具有DataBinding的系列

问题描述

我有一个项目，其中有一个图表区域。 我为此选择了LiveCharts（http://lvcharts.net）。

到目前为止，当在xaml中添加时，该图表可与数据绑定一起使用：

<UserControl x:Class="Work_Task_Planner_Sheduler.Views.TeamTaskProgressChartView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:Work_Task_Planner_Sheduler.Views"
             xmlns:lvc="clr-namespace:LiveCharts.Wpf;assembly=LiveCharts.Wpf"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="800">
    <Grid>
        <lvc:CartesianChart x:Name="TeamTaskProgressChartComponent">
            <lvc:CartesianChart.Series>
                <lvc:Lineseries Title="Julian" Values="{Binding Taskprogress_julian}" />
            </lvc:CartesianChart.Series>
            <lvc:CartesianChart.AxisX>
                <lvc:Axis Title="Time"></lvc:Axis>
            </lvc:CartesianChart.AxisX>
            <lvc:CartesianChart.AxisY>
                <lvc:Axis Title="TaskProgress"></lvc:Axis>
            </lvc:CartesianChart.AxisY>
        </lvc:CartesianChart>
    </Grid>
</UserControl>

问题是：Line系列以xaml进行硬编码。谁知道随着时间的推移团队会变大还是变小，或者团队成员会发生变化。因此，我想在运行时创建线系列。

这是我到目前为止的内容，不幸的是该系列仍然为空：

CartesianChart chart = this.TeamTaskProgressChartComponent;
foreach(string user in TeamMembers)
{
    Lineseries lineseries = new Lineseries();
    string title = user.Split('.')[0];
    lineseries.Title = title;
    Binding databinding = new Binding();
    databinding.source =
    Datarefresh.mainWindow.mainviewmodel.TeamTaskProgressChartviewmodel.TaskProgressCounts;
    DependencyProperty LineseriesProperty = DependencyProperty.Register(title+"Property",typeof(int),typeof(Lineseries),new PropertyMetadata(0));
    lineseries.SetBinding(LineseriesProperty,databinding);
    chart.series.Add(lineseries);
}

解决方法

您必须设置绑定的来源。

CartesianChart chart = new CartesianChart();
foreach(string user in TeamMembers)
{
    LineSeries lineseries = new LineSeries();
    string title = user.Split('.')[0];
    lineseries.Title = title;
    Binding databinding = new Binding("Taskprogress_"+title);

    //===========Set source here before setting the binding to the lineseries===========
    databinding.Source = "your datasource";

    // the following line is pseudocode derived from Microsoft reference
    // https://docs.microsoft.com/en-us/dotnet/desktop/wpf/data/how-to-create-      a-binding-in-code?view=netframeworkdesktop-4.8
    lineseries.SetBinding(LineSeries.Values,databinding); 
}

,

实际上，过程非常简单：

1. 创建系列归类。重要说明：必须在构造函数中初始化series集合，以便在加载图表时可以使用它：

   public class TeamTicketResolveChartViewModel
   {
       public SeriesCollection ChartSeries { get; set; }
       public string[] TicketResolveLabels { get; set; }
   
       public TeamTicketResolveChartViewModel()
       {
           ChartSeries = new SeriesCollection();
           foreach (string user in TeamMembers.ServiceDesk)
           {
               LineSeries lineseries = new LineSeries();
               string title = user.Split('.')[0];
               lineseries.Title = title;
               ChartSeries.Add(lineseries);
           }
       }
       // other functions
   }
   

2. 在xaml中，将图表绑定到系列Collection：

   <lvc:CartesianChart x:Name="TeamTicketResolveChartComponent" Series="{Binding ChartSeries}" />
   

3. 现在更新图表数据将按预期进行：

   public void LoadChartData2(List<List<(DateTime time,int resolved)>> input)
   {
       for (int i = 0; i < input.Count; i++)
       {
           ChartSeries[i].Values = new ChartValues<int>(input[i].Select(c => c.resolved));
       }
   
       DateTime[] dates = input[0].Select(c => c.time).ToArray();
       List<string> labels = new List<string>();
       foreach (DateTime time in dates) labels.Add(time.ToString("HH:mm:ss"));
       TicketResolveLabels = labels.ToArray();
   }
   public void AddChartPoint(List<List<(DateTime time,int resolved)>> input)
   {
       // Chartseries[i].values.Add()
   }