Indicator

The base class of a hybrid indicator.

VolSysAPI.Indicators.Indicator (in VolSysAPI.dll) is the class every hybrid indicator derives from. Members marked desktop are [DesktopOnly], see Desktop only features.

Registration

public static IndicatorDescriptionBase Register()

A static method the indicator must declare. Deepchart finds the indicators of a dll by it.

IndicatorDescriptionBase	Meaning
Name	name in the indicator list
Description	short text shown with the name
HelpLink	address of a help page
Tags	words used by the search of the list

What the indicator works with

Member	Type	Meaning
VAn	IMethodCloudAPI	the chart API
IndVars.Ann_List	IAnnGroup	group of the annotations of the indicator
IndVars.FrontAnnList	IAnnGroup	annotations drawn on the foreground
AxisX, AxisY	IAxis	axes of the area of the indicator, available from OnInit
ChartArea	ChartAreaRef	the area the user placed the indicator in
IndPrms	BaseIndicatorPrms	settings chosen by the user, series settings included
TradingApi	ITradingAPI	orders and positions. desktop

Methods to override

Method	Called
OnSet(bool setDefault, bool themeOverride)	before every load and when a parameter changes. The only one you must override
OnPreInit(), OnInit()	once per load, before the series exist
OnLoad()	before the first bar
OnOpen(bool isRt)	a new bar
OnTick(TickByTick tick, bool isRt, AggrInfo aggrInfo)	a trade
OnClose(bool isRt)	a bar is complete
OnEnd(bool isRt)	after the history, and after every batch of realtime updates
OnDispose()	the indicator is removed
OnSaveProperty()	the settings are about to be saved. Never called on the server
OnBook(BookUpdate updates)	order book changes. desktop
OnResizeAxis(bool isFinal)	the axes are being resized. desktop

See Life cycle for the order.

Set in OnSet

Property	Meaning
OnOpenCall, OnCloseCall, OnTickCall, OnEndCall	which calls the indicator wants: Off, RT, HistRT
OnBookCall, OnResizeCall, OnFundInfoCall	desktop
NeedVbp	the indicator reads the volume by price of the bars
Description	text shown next to the name on the chart

Other properties

Property	Meaning
StatusMessage	message for the user shown when the chart has loaded. Set in OnInit or OnLoad
NeedRecalculate	set to true to ask for a new calculation from the first bar
IsValid	false when the indicator has been stopped after an error

Helpers

Method	Meaning
GetSeriesDefinitions()	the series declared by the indicator, in plot order
GetSeries(definition)	the settings the user chose for a series (Series_Prop)
SetYAxisConstraints(...)	margins and limits of the Y axis in one call