Wpf 如何将多个系列动态绑定到堆叠柱形图

我正在使用DevExpress图表，但我认为大多数图表工具的绑定应该是相同的。下面是一些使用WPF图表工具的示例代码。代码可能不是100%正确，但我想给出一个我需要的大概概念。（我的问题列在后面）

绑定到以下内容：

public IEnumerable FirstCollection
{
    get
    {
        List<KeyValuePair<string, long> kvp = new List<KeyValuePair<string, long>>();
        kvp.Add(new KeyValuePair<string, long>("2015", 200);
        kvp.Add(new KeyValuePair<string, long>("2016", 200);
        kvp.Add(new KeyValuePair<string, long>("2017", 200);
        return kvp;
    }
    set{
        NotifyPropertyChanged(FirstCollection);
    }

}
public IEnumerable SecondCollection
{
    get
    {
        List<KeyValuePair<string, long> kvp = new List<KeyValuePair<string, long>>();
        kvp.Add(new KeyValuePair<string, long>("2015", 200);
        kvp.Add(new KeyValuePair<string, long>("2016", 200);
        kvp.Add(new KeyValuePair<string, long>("2017", 200);
        return kvp;
    }
    set{
        NotifyPropertyChanged(SecondCollection);
    }

}

public IEnumerable FirstCollection
{
得到
{
名单
public IEnumerable FirstCollection
{
    get
    {
        List<KeyValuePair<string, long> kvp = new List<KeyValuePair<string, long>>();
        kvp.Add(new KeyValuePair<string, long>("2015", 200);
        kvp.Add(new KeyValuePair<string, long>("2016", 200);
        kvp.Add(new KeyValuePair<string, long>("2017", 200);
        return kvp;
    }
    set{
        NotifyPropertyChanged(FirstCollection);
    }

}
public IEnumerable SecondCollection
{
    get
    {
        List<KeyValuePair<string, long> kvp = new List<KeyValuePair<string, long>>();
        kvp.Add(new KeyValuePair<string, long>("2015", 200);
        kvp.Add(new KeyValuePair<string, long>("2016", 200);
        kvp.Add(new KeyValuePair<string, long>("2017", 200);
        return kvp;
    }
    set{
        NotifyPropertyChanged(SecondCollection);
    }

}