LiveCharts WPF中单独着色的数据点 [英] Individually colored data points in LiveCharts WPF

问题描述

我正在使用Live Charts WPF绘制一些图表.为了使每个柱形条具有不同的颜色，我添加了多个系列，但没有显示所有系列的x-axis标签.为什么?

I am using Live Charts WPF to draw some charts. To make each column bar of different color I added multiple series, but it doesn't show x-axis labels of all series. Why?

senderChart.Series = new SeriesCollection();
    int i = 0;
   var ax = new Axis
   {
       Separator = new LiveCharts.Wpf.Separator()
       {
           Step = 1
       },
       Labels = dateValues,
       ShowLabels = true
   };
   senderChart.AxisX.Add(ax);
    foreach (var val in dataValues)
    {
        senderChart.Series.Add(new ColumnSeries
        {
            DataLabels = true,
            Title = dateValues[i],
            Values = new ChartValues<double>{val},
        });
        i++;
    }  

我还尝试了将图表分配系列的几乎所有不同方法，但仍然得到了相同的结果.

I also have tried almost every different way of assigning series to chart but still got same result.

推荐答案

您有20个系列，但是每个系列只有一个数据点，因此为什么只有一个标签.仅使用一个系列将更接近LiveCharts的预期用途.然后，您可以通过引入映射器( 更多信息).

You have 20 series, but each of them only has a single data point, that is why you only get one label. Using only a single series would be closer to LiveCharts’ intended use. You can then control the bar color by introducing a mapper (further info).

这里是一个例子:

//create the mapper
var dapperMapper = new CartesianMapper<double>()
    //the data point will be displayed at the position of its index on the X axis
    .X((value, index) => index)
    //the data point will have a Y value of its value (your double) aka the column height
    .Y((value) => value)
    //pass any Func to determine the fill color according to value and index
    //in this case, all columns over 3 height will be pink
    //in your case, you want this to depend on the index
    .Fill((value, index) => (value > 3.0 ? Brushes.HotPink : Brushes.YellowGreen));

//assign the mapper globally (!)
LiveCharts.Charting.For<double>(dapperMapper, SeriesOrientation.Horizontal);

这样，您就可以使用每月价值一个的单个系列.您可以将Fill Func设为类似这样的颜色，在其中循环显示12种颜色.

With that, you can use a single series with one value per month. You could have your Fill Func be something like this, where it cycles through 12 colors.

下面是一个完整的示例，其名称与您的名字相近:

Here is a full example with names close to yours:

public partial class MainWindow : Window
{
    public SeriesCollection senderChart { get; set; }
    public double[] dataValues = { 1, 7, 4, 8, 3, 12, 4, 3, 2, 21, 4, 2, 7, 3, 23, 34, 5, 47, 2, 3, 45, 58, 3, 4 };
    public string[] dateValues = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
                                 , "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };

    public MainWindow()
    {
        var doubleMapperWithMonthColors = new LiveCharts.Configurations.CartesianMapper<double>()
            .X((value, index) => index)
            .Y((value) => value)
            .Fill((v, i) =>
            {
                switch (i % 12)
                {
                    case  0: return Brushes.LightBlue; //january
                    case  1: return Brushes.LightCoral; //february
                    case  2: return Brushes.PaleGoldenrod; //march
                    case  3: return Brushes.OrangeRed; //april
                    case  4: return Brushes.BlueViolet; //may
                    case  5: return Brushes.Chocolate; //june
                    case  6: return Brushes.PaleVioletRed; //july
                    case  7: return Brushes.CornflowerBlue; //august
                    case  8: return Brushes.Orchid; //september
                    case  9: return Brushes.Thistle; //october
                    case 10: return Brushes.BlanchedAlmond; //november
                    case 11: return Brushes.YellowGreen; //december 
                    default: return Brushes.Red;
                }
            });

        LiveCharts.Charting.For<double>(doubleMapperWithMonthColors, SeriesOrientation.Horizontal);



        senderChart = new SeriesCollection();

        var columnSeries = new ColumnSeries() { Values = new ChartValues<double>(), DataLabels = true, Title = "Appointments" };
        var labels = this.dateValues;

        foreach (var val in dataValues)
        {
            columnSeries.Values.Add(val);
        }

        this.senderChart.Add(columnSeries);

        DataContext = this;
    }
}

XAML:

<Window x:Class="WpfApp1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:lvc="clr-namespace:LiveCharts.Wpf;assembly=LiveCharts.Wpf"
        Title="MainWindow" Height="400" Width="900">
        <lvc:CartesianChart Series="{Binding senderChart}" Margin="48, 48, 48, 24">
            <lvc:CartesianChart.AxisX>
                <lvc:Axis Labels="{Binding Labels}">
                    <lvc:Axis.Separator>
                        <lvc:Separator Step="1" Stroke="{x:Null}"/>
                    </lvc:Axis.Separator>
                </lvc:Axis>
            </lvc:CartesianChart.AxisX>
        </lvc:CartesianChart>
</Window>

结果:

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