cdk_dscale(3)

NAME
cdk_dscale - curses scale widget (type double).

SYNOPSIS

cc [ flag ... ] file ... -lcdk [ library ... ]

#include <cdk.h>

double activateCDKDScale (
    CDKDSCALE *scale,
    chtype *actions);

void destroyCDKDScale (
    CDKDSCALE *scale);

void drawCDKDScale (
    CDKDSCALE *scale,
    boolean box);

void eraseCDKDScale (
    CDKDSCALE *scale);

boolean getCDKDScaleBox (
    CDKDSCALE *scale);

int getCDKDScaleDigits (
    CDKDSCALE *scale);

double getCDKDScaleHighValue (
    CDKDSCALE *scale);

double getCDKDScaleLowValue (
    CDKDSCALE *scale);

double getCDKDScaleValue (
    CDKDSCALE *scale);

int injectCDKDScale (
    CDKDSCALE *scale,
    chtype input);

void moveCDKDScale (
    CDKDSCALE *scale,
    int xpos,
    int ypos,
    boolean relative,
    boolean refresh);

CDKDSCALE *newCDKDScale (
    CDKSCREEN *cdkscreen,
    int xpos,
    int ypos,
    const char *title,
    const char *label,
    chtype fieldAttribute,
    int fieldWidth,
    double currentValue,
    double lowValue,
    double highValue,
    double increment,
    double fastIncrement,
    int digits,
    boolean box,
    boolean shadow);

void positionCDKDScale (
    CDKDSCALE *scale);

void setCDKDScale (
    CDKDSCALE *scale,
    double lowValue,
    double highValue,
    double currentValue,
    boolean box);

void setCDKDScaleBackgroundAttrib (
    CDKDSCALE *scale,
    chtype attribute);

void setCDKDScaleBackgroundColor (
    CDKDSCALE *scale,
    const char * color);

void setCDKDScaleBox (
    CDKDSCALE *scale,
    boolean box);

void setCDKDScaleBoxAttribute (
    CDKDSCALE *scale,
    chtype character);

void setCDKDScaleDigits (
    CDKDSCALE *scale,
    int digits);

void setCDKDScaleHorizontalChar (
    CDKDSCALE *scale,
    chtype character);

void setCDKDScaleLLChar (
    CDKDSCALE *scale,
    chtype character);

void setCDKDScaleLRChar (
    CDKDSCALE *scale,
    chtype character);

void setCDKDScaleLowHigh (
    CDKDSCALE *scale,
    double low,
    double high);

void setCDKDScalePostProcess (
    CDKDSCALE *scale,
    PROCESSFN callback,
    void * data);

void setCDKDScalePreProcess (
    CDKDSCALE *scale,
    PROCESSFN callback,
    void * data);

void setCDKDScaleULChar (
    CDKDSCALE *scale,
    chtype character);

void setCDKDScaleURChar (
    CDKDSCALE *scale,
    chtype character);

void setCDKDScaleValue (
    CDKDSCALE *scale,
    double value);

void setCDKDScaleVerticalChar (
    CDKDSCALE *scale,
    chtype character);

DESCRIPTION
The Cdk scale widget creates a scale box with a label and a scale field. The following functions create or manipulate the Cdk scale box widget.

AVAILABLE FUNCTIONS

activateCDKDScale
    activates the scale widget and lets the user interact with the widget.
    The parameter scale is a pointer to a non-NULL scale widget. If the actions parameter is passed with a non-NULL value, the characters in the array will be injected into the widget.

        To activate the widget interactively pass in a NULL pointer for actions.

        If the character entered into this widget is RETURN or TAB then this function will return a value from the low value to the high value. It will also set the widget data exitType to vNORMAL.

        If the character entered into this widget was ESCAPE then the widget will return the unknownDouble value (see the cdk_objs.h header file).

    The widget data exitType will be set to vESCAPE_HIT.

destroyCDKDScale
    removes the widget from the screen and frees memory the object used.

drawCDKDScale
    draws the scale widget on the screen.

    If the box parameter is true, the widget is drawn with a box.

eraseCDKDScale
    removes the widget from the screen. This does NOT destroy the widget.

getCDKDScaleBox
    returns whether the widget will be drawn with a box around it.

getCDKDScaleDigits
    returns the number of digits shown after the decimal point for the box value.

getCDKDScaleHighValue
    returns the high value of the scale widget.

getCDKDScaleLowValue
    returns the low value of the scale widget.

getCDKDScaleValue
    returns the current value of the widget.

injectCDKDScale
    injects a single character into the widget.
    The parameter scale is a pointer to a non-NULL scale widget. The parameter character is the character to inject into the widget.

    The return value and side-effect (setting the widget data exitType) depend upon the injected character:

    RETURN or TAB
        the function returns a value ranging from the scale's low value to the scale's high value. The widget data exitType is set to vNORMAL.

    ESCAPE
        the function returns the unknownDouble value (see the cdk_objs.h header file). The widget data exitType is set to vESCAPE_HIT.

    Otherwise
        unless modified by preprocessing, postprocessing or key bindings, the function returns the unknownDouble value (see the cdk_objs.h header file). The widget data exitType is set to vEARLY_EXIT.

moveCDKDScale
    moves the given widget to the given position.
    The parameters xpos and ypos are the new position of the widget.

        The parameter xpos may be an integer or one of the pre-defined values TOP, BOTTOM, and CENTER.

        The parameter ypos may be an integer or one of the pre-defined values LEFT, RIGHT, and CENTER. The parameter relative states whether the xpos/ypos pair is a relative move or an absolute move.

        For example, if xpos = 1 and ypos = 2 and relative = TRUE, then the widget would move one row down and two columns right. If the value of relative was FALSE then the widget would move to the position (1,2).

        Do not use the values TOP, BOTTOM, LEFT, RIGHT, or CENTER when relative = TRUE. (weird things may happen). The final parameter refresh is a boolean value which states whether the widget will get refreshed after the move.

newCDKDScale
    creates a pointer to a scale widget. Parameters:

    screen
        is the screen you wish this widget to be placed in.

    xpos
        controls the placement of the object along the horizontal axis. It may be an integer or one of the pre-defined values LEFT, RIGHT, and CENTER.

    ypos
        controls the placement of the object along the vertical axis. It may be an integer or one of the pre-defined values TOP, BOTTOM, and CENTER.

    title
        is the string to display at the top of the widget. The title can be more than one line; just provide a carriage return character at the line break.

    label
        is the string to display in the label of the scale field.

    fieldAttribute
        is the attribute of the characters displayed in the field.

    fieldWidth
        controls the width of the widget. If you provide a value of zero the widget will be created with the full width of the screen. If you provide a negative value, the widget will be created the full width minus the value provided.

    currentValue
        is the value of the scale field when the widget is activated.

    lowValue and

    highValue
        are the low and high values of the widget respectively.

    increment
        is the regular increment value

    fastIncrement
        is the accelerated increment value.

    box is true if the widget should be drawn with a box around it.

    shadow
        turns the shadow on or off around this widget.

    If the widget could not be created then a NULL pointer is returned.

positionCDKDScale
    allows the user to move the widget around the screen via the cursor/keypad keys. See cdk_position (3) for key bindings.

setCDKDScale
    lets the programmer modify certain elements of an existing scale widget.

    The parameter names correspond to the same parameter names listed in the newCDKDScale function.

setCDKDScaleBackgroundAttrib
    sets the background attribute of the widget.

    The parameter attribute is a curses attribute, e.g., A_BOLD.

setCDKDScaleBackgroundColor
    sets the background color of the widget.

    The parameter color is in the format of the Cdk format strings.

    See cdk_display (3).

setCDKDScaleBox
    sets whether the widget will be drawn with a box around it.

setCDKDScaleBoxAttribute
    sets the attribute of the box.

setCDKDScaleDigits
    sets the number of digits shown after the decimal point for the box value.

setCDKDScaleHorizontalChar
    sets the horizontal drawing character for the box to the given character.

setCDKDScaleLLChar
    sets the lower left hand corner of the widget's box to the given character.

setCDKDScaleLRChar
    sets the lower right hand corner of the widget's box to the given character.

setCDKDScaleLowHigh
    sets the low and high values of the widget.

setCDKDScalePostProcess
    allows the user to have the widget call a function after the key has been applied to the widget.
    The parameter function is the callback function. The parameter data points to data passed to the callback function.

    To learn more about post-processing see cdk_process (3).

setCDKDScalePreProcess
    allows the user to have the widget call a function after a key is hit and before the key is applied to the widget.
    The parameter function is the callback function. The parameter data points to data passed to the callback function.

    To learn more about pre-processing see cdk_process (3).

setCDKDScaleULChar
    sets the upper left hand corner of the widget's box to the given character.

setCDKDScaleURChar
    sets the upper right hand corner of the widget's box to the given character.

setCDKDScaleValue
    sets the current value of the widget.

setCDKDScaleVerticalChar
    sets the vertical drawing character for the box to the given character.

KEY BINDINGS
When the widget is activated there are several default key bindings which will help the user enter or manipulate the information quickly. The following table outlines the keys and their actions for this widget.

Key | Action
Down Arrow | Decrements the scale by the normal value.
Up Arrow | Increments the scale by the normal value.
u | Increments the scale by the normal value.
Prev Page | Decrements the scale by the accelerated value.
U | Decrements the scale by the accelerated value.
Ctrl-B | Decrements the scale by the accelerated value.
Next Page | Increments the scale by the accelerated value.
Ctrl-F | Increments the scale by the accelerated value.
Home | Sets the scale to the low value.
g | Sets the scale to the low value.
^ | Sets the scale to the low value.
End | Sets the scale to the high value.
G | Sets the scale to the high value.
$ | Sets the scale to the high value.
Return | Exits the widget and returns the index of the selected value. This also sets the widget data exitType to vNORMAL.
Tab | Exits the widget and returns the index of the selected value. This also sets the widget data exitType to vNORMAL.
Escape | Exits the widget and returns the unknownDouble value (see the cdk_objs.h header file). This also sets the widget data exitType to vESCAPE_HIT.
Ctrl-R | Refreshes the screen.

If the cursor is not pointing to the field's value, the following key bindings apply. You may use the left/right arrows to move the cursor onto the field's value and modify it by typing characters to replace the digits and sign.
Key | Action
Left Arrow | Decrements the scale by the normal value.
Right Arrow | Increments the scale by the normal value.
d | Decrements the scale by the normal value.
D | Increments the scale by the accelerated value.
- | Decrements the scale by the normal value.
+ | Increments the scale by the normal value.
0 | Sets the scale to the low value.

SEE ALSO
cdk(3), cdk_binding(3), cdk_display(3), cdk_position(3), cdk_screen(3)