带有 LiveCharts 的 WPF 在运行时添加带有 DataBinding 的系列

Posted 2023-02-23

【中文标题】带有 LiveCharts 的 WPF 在运行时添加带有 DataBinding 的系列

【英文标题】：WPF with LiveCharts add series with DataBinding at runtime

【发布时间】：2021-02-19 02:12:44

【问题描述】：

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

到目前为止一切顺利，当添加到 xaml 中时，图表可以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 系列在 xaml 中是硬编码的。谁知道团队是否会随着时间的推移而变大/变小，或者团队成员是否会发生变化。因此我想在运行时创建线系列。

这是我目前所拥有的，不幸的是该系列仍然是空的：

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);

【参考方案1】：

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); 

【讨论】：

我已经更新了我的代码。我现在可以编译并运行该应用程序，但该系列仍为空。这在 xaml 中定义相同时有效

【参考方案2】：

其实过程很简单：

创建一个系列排序规则。重要提示：必须在构造函数中初始化系列集合，以便在加载图表时准备好：

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

在xaml中，将图表绑定到系列Collection：

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

现在更新图表数据将按预期工作：

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()