Question

I have a line series chart called “lineSeries1”.

I would like that chart to be filled and updated during runtime, depending of two variables. “currentPos” would be the X axis, and “budget” would be the Y axis. Also, “budget” is possible to change value during runtime.

Basically, I would just like to know how to set values in the chart, programmatically. For example, whenever a new currentPos/budget is created, or when an existing budget is modified.

How can I pull that off in Silverlight C#? there is very little documentation on that online…

EDIT: after some research, I came upon this tutorial: http://www.a2zdotnet.com/View.aspx?Id=136. With some inspiration from that site, I came up with my own code, which doesn’t work…

Here’s my XAML:

<toolkit:Chart x:Name="theChart">

        <toolkit:LineSeries x:Name="lineSeries1" DependentValuePath="CurrentPos" IndependentValuePath="Budget"></toolkit:LineSeries>

    </toolkit:Chart>

Here’s my class:

public class oneEvent
{
    private int _CurrentPos;
    private int _Budget;

    public oneEvent(int currentPos, int budget)
    {
        _CurrentPos = currentPos;
        _Budget = budget;
    }

    public int CurrentPos
    {
        get { return _CurrentPos; }
        set { _CurrentPos = value; }
    }

    public int Budget
    {
        get { return _Budget; }
        set { _Budget = value; }
    }
}

and here’s my code which populates the lines chart:

public MainPage()
    {
        InitializeComponent();

        List<oneEvent> list = new List<oneEvent>();
        list.Add(new oneEvent(0, 8000));
        list.Add(new oneEvent(1, 9000));
        list.Add(new oneEvent(2, 10000));
        list.Add(new oneEvent(3, 11000));
        list.Add(new oneEvent(4, 12000));
        list.Add(new oneEvent(5, 9000));
        list.Add(new oneEvent(6, 500));
        list.Add(new oneEvent(7, 1000));

        try
        {
            lineSeries1.ItemsSource = list;
        }
        catch (System.Exception excep)
        {
            MessageBox.Show(excep.Message);
        }
    }

When I run this, I get a message box saying “object reference not set to an instance of an object”. What am I doing wrong?

EDIT:
ok, figured out my problem.
Instead of writing lineSeries1.ItemsSource = list;,
I should’ve written LineSeries lineseries = theChart.Series[0] as LineSeries;
lineseries.ItemsSource = list;
I don’t know why, but it works…

Answer 1

ok, figured out my problem. Instead of writing

lineSeries1.ItemsSource = list;

, I should’ve written

LineSeries lineseries = theChart.Series[0] as LineSeries;
lineseries.ItemsSource = list;

I don’t know why, but it works…