StripChart(3X) — DeltaWindows 1.3.3 Release 4 Version 4.3

NAME

StripChart widget − widget to display a real-time graphic chart.

SYNOPSIS

Public Headers:<X11/StringDefs.h> <X11/Xaw/StripChart.h>

Private Header:<X11/Xaw/StripCharP.h>

Class Name:StripChart

Class Pointer:stripChartWidgetClass

Instantiation:widget = XtCreateWidget(name, stripChartWidgetClass, ...)

CLASS HIERARCHY

Core → Simple → StripChart

DESCRIPTION

The StripChart widget is used to provide a real-time graphic chart of a single value. This widget is used by xload to provide the load graph. It will read data from an application, and update the chart at the XtNupdate interval specified.

RESOURCES

When creating a StripChart widget instance, the following resources are retrieved from the argument list or from the resource database:

Name (XtN...)	Class Type	Default	Description

XtNaccelerators	AcceleratorTable	NULL	List of event-to-action bindings to be executed by this widget, even though the event occurred in another widget.
XtNancestor− Sensitive	Boolean	True	(D) Sensitivity state of the ancestors of this widget: a widget is insensitive if either it or any of its ancestors is insensitive.
XtNbackground	Pixel	XtDefault− Background	Window background color.
XtNbackground− Pixmap	Pixmap	XtUnspecified− Pixmap	Window background pixmap.
XtNborderColor	Pixel	XtDefault− Foreground	Window border color.
XtNborderPixmap	Pixmap	XtUnspecified− Pixmap	Window border pixmap.
XtNborderWidth	Dimension	1	Border width in pixels.
XtNcolormap	Colormap	Parent’s colormap.	Colormap that this widget will use.
XtNcursor	Cursor	None.	Pointer cursor.
XtNdepth	int	Parent’s depth.	(C) Depth of this widget’s window.
XtNdestroy− Callback	XtCallbackList	NULL	Callbacks for XtDestroyWidget().
XtNforeground	Pixel	XtDefault− Foreground	Foreground color.
XtNgetValue	Callback	NULL	See below.
XtNheight	Dimension	Font height + 2 ∗ XtNinternalHeight	Height of widget.
XtNhighlight	Pixel	XtDefault− Foreground	See below.
XtNinsensitive− Border	Pixmap	Gray pixmap.	Border when not sensitive.
XtNjumpScroll	int	Half the width of the widget.	(A) See below.
XtNmappedWhen− Managed	Boolean	TRUE	Whether XtMapWidget() is automatic.
XtNminScale	int	1	See below.
XtNscreen	Screen	Parent’s screen.	(R) Screen on which this widget is displayed.
XtNsensitive	Boolean	TRUE	Whether widget receives input.
XtNtranslations	Translation− Table	See below.	Event-to-action translations.
XtNupdate	int	10	See below.
XtNwidth	Dimension	0	The height and width of this widget in pixels.
XtNx	Position	0	x-coordinate in pixels.
XtNy	Position	0	y-coordinate in pixels.

The new resources (not inherited from superclasses) associated with the StripChart widget are:

XtNgetValueThis is a list of functions to call every XtNupdate seconds. This function will get the value to be graphed by the StripChart widget. The section below, Getting the StripChart Value, describes the calling interface in more detail. This callback list should contain only one function. If this callback list contains more than one function, the behavior is undefined.

XtNhighlight
A pixel value which indexes the widget’s colormap to derive the color that will be used to draw the scale lines on the graph.

XtNjumpScroll
When the graph reaches the right edge of the window it must be scrolled to the left. This resource specifies the number of pixels it will jump. Smooth scrolling can be achieved by setting this resource to 1.

XtNminScaleThe minimum scale for the graph. The number of divisions on the graph will always be greater than or equal to this value.

XtNupdateThe number of seconds between graph updates. Each update is represented on the graph as a 1 pixel wide line. Every XtNupdate seconds the getValue procedure will be used to get a new graph point, and this point will be added to the right end of the StripChart.

GETTING THE STRIPCHART VALUE

The StripChart widget will call the application routine passed to it as the XtNgetValue callback function every XtNupdate seconds to obtain another point for the StripChart graph. The calling interface for the XtNgetValue callback is: void (∗getValueProc)(w, client_data, value)
     Widget w;
     XtPointer client_data;
     XtPointer value;    /∗ double ∗ ∗/

wSpecifies the StripChart widget.

client_data
Specifies the client data.

valueReturns a pointer to a double. The application should set the address pointed to by this argument to a double containing the value to be graphed on the StripChart.