4.2 Indicator

Indicator is the alpha-numeric one-row window where you can put data or character strings. But there is a difference between Indicator and a real window (such as an Outbox). When you declare Indicator you must specify the format of the data output and this restricts you on what you can put on Indicator. On the other hand this simplifies the subsequent programming. In most of cases indicator is used to display only one variable, e.g. temperature or voltage. It is reasonable to attach this variable to Indicator. We defined Indicator as the template class with one type parameter T - the type of the attached variable.

Constructor:

Indicator(
int x0,int y0, // coord. of LEFT-TOP corner of Indicator
objtype type, // may be FIXED, PERM, POPUP
char * title, // title of Indicator
int dispwidth, // width of display in characters
T *variable, // pointer to variable attached to indicator
char *format, // format of indicated data
//———- Hereafter are defaults
int frame=UNFRAMED,// display may FRAMED or UNFRAMED
// proc supplied by programmer to repaint Indicator
void (far *paintproc)()=procNULL,// only for PERM indicators
int datafont=0,int datafontsize=1, // font of indicated data
int titlefont=0,int titlefontsize=1, // font of title
plaquecolors indframecolcnfg=plaquecoldflt,// colors of frame
indicatorcolors indcolcnfg=LCDdark); // colors of screen and data

The format parameter is the string analogous to that used in the standard printf function. The frame parameter is reasonable to change to FRAMED when you use POPUP or PERM type of Indicator, and leave UNFRAMED when you use FIXED type, because FIXED type Indicator is usually embedded in the board or panel. You have to keep in mind that changing the default data font will slow down the overall performance, because displaying the vector fonts takes excessive time. The indcolcnfg defines the color scheme. There are four pre-defined color schemes for Indicator:
LEDind - red light-emitting diodes,
LUMind - green cathode-ray display,
LCDdark - liquid crystal display,
LCDbright - back-lit liquid crystal display.

Example: 

Indicator<float> *pindTemp = new Indicator<float>
      (0,0,FIXED,"Temperature",
       10,                     // width of disp. in chars
       &Temp,"%.2f K",         // variable and format, temperature in Kelvin
       UNFRAMED,procDummy,     // no paint proc. defined
       0,1,                    // font and size of number
       SMALL_FONT,4);          // font and size of title

Unframed indicator pindTemp is initialized at the left top corner of the screen. Later in the program, when the true location of pindTemp will be calculated, you can use MovetoXY method, inherited from the object base class, to relocate pindTemp before painting.

If you don't want to attach any variable to the indicator you can use class _Indicator (it is not a template class). Then in the constructor you must omit the parameter variable and you cannot use Refresh method.

Data members:

All are inherited from the object base class (sect.4).

Methods:

Includes methods inherited from the object base class (sect.4).

void cls();

Clears display. Inherited from display class.

virtual void Paint(void);

Paints the indicator and clears its display.

void Refresh(void);

Clears the display and puts the value of the attached variable in accordance with the format defined in the constructor.

void Put(...);

Puts data on the display in accordance with the format defined in the constructor. You may consider it is as pritnf( format, ...).

Example: 

\hspace{2cm} pindTemp->Put( 77.2);
or
\hspace{2cm} Temp=77.2;  pindTemp->Refresh();
Here pindTemp is declared in the preceding example. After the execution of one of these fragments the indicator will display: " 77.2 K".

void Puts(char *str);

Puts string str on the indicator. This method doesn't use format. So you can display on the indicator any message that fits the width of indicator.

Example: 

   pindTemp->Puts( "Overflow");
Color schemes:

Color pattern for Indicator is provided by the structure:

struct indicatorcolors{ COLORS
title, // color of title
foregr, // foreground color
backgr; // background color
};

There are four pre-defined color schemes for Indicator:
LEDind, LUMind, LCDdark, LCDbright.