Using the Chart Component in Extensions

This document describes how to use the Chart components in Wealth-Lab 8 in your own Extensions. The Chart components are located in the WealthLab.ChartWPF assembly, so reference this assembly in addition to the other ones required for your Extension.

Note: for a complete example of using the Chart components in an Extension, see our open source Extension Demo Project on GitHib.

The Chart Components in WealthLab.ChartWPF are organized into two primary classes:

• CoreChart - The stripped down chart without toolbar and status bar
• Chart - A higher level chart that contains a CoreChart, toolbar, and status bar

Accessing the Host (WL8) Environment

The IHost interface allows your extension to access information about the user's WealthLab environment. For example, the location of the user data folder, or obtaining a list of DataSets defined by the user. At any point in your extension's code base, you can access an instance of the IHost interface using the singleton class WLHost and its Instance property. Example:

//get user data folder
string folder = WLHost.Instance.DataFolder;

Working with CoreChart

The first tab of the Extension Demo Project contains 4 CoreChart instances in a 2x2 grid. Examine the XAML and CS code for an example of how to bring the CoreChart into your project code base.

public void Refresh(bool fullRefresh)

Causes the chart to refresh. Can be used to force a refresh after changing some properties in its ChartPreferences, for example. The chart uses two-pass rendering logic, where the first path renders the underlying bars of data, and the second pass renders only the transient elements like cursors. The fullRefresh parameter controls whether both rendering passes will occur (true) or only the second pass (false).

public BarHistory Bars

Assign a BarHistory instance to the Bars property to cause that data to be plotted in the chart.

public ChartPreferences ChartPreferences

An instance of the ChartPreferences class that contain the cosmetic settings the chart will use to render. Assigning a new value to this property causes the chart to refersh with the new settings.

public bool IsCrosshairEnabled
public bool IsVerticalBarEnabled

Controls whether the respective chart cursors are visible.

public bool IsStreaming

Controls whether the chart is streaming. If you assign true, the chart will use the most recently selected Streaming Data Provider.

public bool ActivateStreamingWith(StreamingProviderBase sb)

Lets you begin streaming with a specific Streaming Data Provider.

Note: CoreChart has many more properties, methods and events, and we will continue to flesh out this document as time goes on. For answers to any particular questions, please use our Discussion Forum.

Working with Chart

The second tab of the Extension Demo Project contains a Chart component that accepts user-selected Indicators for plotting. Examine the XAML and CS code for an example of how to bring the Chart into your project code base.

public void ChartThisSymbol(string symbol, DataSet ds = null)

Causes the chart to load data for the specified symbol, optionally using the DataSet specified in ds.

public CoreChart Core

The instance of CoreChart contained in this Chart.

public void InstallContextMenuItem(string text, ImageSource imgsrc, RoutedEventHandler handler)

Lets you add a new menu item to the chart's right click context menu.

public bool AllowStreaming

Controls whether the streaming button should be visible in the chart toolbar.

public bool IsStreaming

Determines whether the chart is streaming.

Note: Chart has many more properties, methods and events, and we will continue to flesh out this document as time goes on. For answers to any particular questions, please use our Discussion Forum.