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cdk_scroll 3 2025-01-14 Library calls

cdk_scroll(3)                   Library calls                  cdk_scroll(3)

NAME

       cdk_scroll - Cdk scrolling list widget

SYNOPSIS

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

       #include <cdk.h>

       int activateCDKScroll (
                      CDKSCROLL *scroll,
                      chtype * actions);

       void addCDKScrollItem (
                      CDKSCROLL *scroll,
                      const char *item);

       void deleteCDKScrollItem (
                      CDKSCROLL *scroll,
                      int position);

       void destroyCDKScroll (
                      CDKSCROLL *scroll);

       void drawCDKScroll (
                      CDKSCROLL *scroll,
                      boolean box);

       void eraseCDKScroll (
                      CDKSCROLL *scroll);

       boolean getCDKScrollBox (
                      CDKSCROLL *scroll);

       int getCDKScrollCurrent(
                      CDKSCROLL *scroll);

       int getCDKScrollCurrentItem (
                      CDKSCROLL *widget);

       chtype getCDKScrollHighlight (
                      CDKSCROLL *scroll,
                      chtype highlight);

       int getCDKScrollCurrentTop (
                      CDKSCROLL *widget);

       int getCDKScrollItems (
                      CDKSCROLL *scroll,
                      char **list);

       int injectCDKScroll (
                      CDKSCROLL *scroll,
                      chtype input);

       void insertCDKScrollItem (
                      CDKSCROLL *scroll,
                      const char *item);

       void moveCDKScroll (
                      CDKSCROLL *scroll,
                      int xpos,
                      int ypos,
                      boolean relative,
                      boolean refresh);

       CDKSCROLL *newCDKScroll (
                      CDKSCREEN *cdkscreen,
                      int xpos,
                      int ypos,
                      int spos,
                      int height,
                      int width,
                      const char *title,
                      CDK_CONST char **itemList,
                      int items,
                      boolean numbers,
                      chtype highlight,
                      boolean box,
                      boolean shadow);

       void positionCDKScroll (
                      CDKSCROLL *scroll);

       void setCDKScroll (
                      CDKSCROLL *scroll,
                      CDK_CONST char **itemList,
                      int items,
                      boolean numbers,
                      chtype highlight,
                      boolean box);

       void setCDKScrollBackgroundAttrib (
                      CDKSCROLL *scroll,
                      chtype attribute);

       void setCDKScrollBackgroundColor (
                      CDKSCROLL *scroll,
                      const char * color);

       void setCDKScrollBox (
                      CDKSCROLL *scroll,
                      boolean box);

       void setCDKScrollBoxAttribute (
                      CDKSCROLL *scroll,
                      chtype character);

       void setCDKScrollCurrent(
                      CDKSCROLL *scroll,
                      intitem);

       void setCDKScrollCurrentItem (
                      CDKSCROLL *widget,
                      intitem);

       void setCDKScrollHighlight (
                      CDKSCROLL *scroll,
                      chtype highlight);

       void setCDKScrollHorizontalChar (
                      CDKSCROLL *scroll,
                      chtype character);

       void setCDKScrollItems (
                      CDKSCROLL *scroll,
                      CDK_CONST char **itemList,
                      int listSize,
                      boolean numbers);

       void setCDKScrollLLChar (
                      CDKSCROLL *scroll,
                      chtype character);

       void setCDKScrollLRChar (
                      CDKSCROLL *scroll,
                      chtype character);

       void setCDKScrollPosition (
                      CDKSCROLL *scroll,
                      intitem);

       void setCDKScrollPostProcess (
                      CDKSCROLL *scroll,
                      PROCESSFN callback,
                      void * data);

       void setCDKScrollPreProcess (
                      CDKSCROLL *scroll,
                      PROCESSFN callback,
                      void * data);

       void setCDKScrollULChar (
                      CDKSCROLL *scroll,
                      chtype character);

       void setCDKScrollURChar (
                      CDKSCROLL *scroll,
                      chtype character);

       void setCDKScrollVerticalChar (
                      CDKSCROLL *scroll,
                      chtype character);

DESCRIPTION

       The  Cdk  scroll  widget creates a scrolling list.  The following are
       functions which create or manipulate the Cdk scrolling list widget.

AVAILABLE FUNCTIONS

       activateCDKScroll
            activates the scroll widget and lets the user interact with  the
            widget.

            o   The parameter scroll points to a non-NULL scroll widget.

            o   If  the  actions  parameter is passed with a non-NULL value,
                the characters in the array will be injected into  the  wid-
                get.

                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  0 to the number of
            items-1, representing the item selected.  It will also  set  the
            widget data exitType to vNORMAL.

            If  the  character entered into this widget was ESCAPE, then the
            widget will return a value of -1 and the  widget  data  exitType
            will be set to vESCAPE_HIT.

       addCDKScrollItem
            allows the user to add an item into an existing scrolling list.

            o   The scroll parameter points to the scrolling list to add the
                item to.

            o   The  parameter item is a char * representing the new item to
                add.  The item is always added to the end of the list.

       deleteCDKScrollItem
            allows the user to add an item into an existing scrolling list.

            o   The scroll parameter points to the scrolling list to add the
                item to.

            o   The parameter f2position is an int which specifies which el-
                ement to remove.

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

       drawCDKScroll
            draws  the  scroll  widget  on the screen.  If the box option is
            true, the widget is drawn with a box.

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

       getCDKScrollBox
            returns true if the widget will be drawn with a box around it.

       getCDKScrollCurrent
            returns the current item's index.

            This  is  deprecated because the name is inconsistent with other
            widgets: use getCDKScrollCurrentItem.

       getCDKScrollCurrentItem
            returns the current item's index in the scroller.

       getCDKScrollHighlight
            returns the attribute of the highlight bar.

       getCDKScrollCurrentTop
            returns the top line of the scroller, counting from zero.

       getCDKScrollItems
            optionally copies the scrolling-list  items  into  the  caller's
            list,  which  must  be large enough since this function does not
            allocate it.  If the list parameter is null, no copying is done.
            It returns the list size whether or not the  list  parameter  is
            null.

       injectCDKScroll
            injects a single character into the widget.

            o   The parameter scroll points to a non-NULL scroll widget.

            o   The  parameter character is the character to inject into the
                widget.

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

            RETURN or TAB
                   the  function  returns  a  value ranging from zero to one
                   less than the number of items, representing the item  se-
                   lected.  The widget data exitType is set to vNORMAL.

            ESCAPE the function returns -1.  The widget data exitType is set
                   to vESCAPE_HIT.

            Otherwise
                   unless  modified  by preprocessing, postprocessing or key
                   bindings, the function returns -1.  The widget data exit-
                   Type is set to vEARLY_EXIT.

       insertCDKScrollItem
            allows the user to add an item into an existing scrolling list.

            o   The scroll parameter points to the scrolling list to add the
                item to.

            o   The parameter item is a char * representing the new item  to
                add.

            The item is always added before the current item in the list.

       moveCDKScroll
            moves the given widget to the given position.

            o   The  parameters  xpos  and  ypos are the new position of the
                widget.

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

                The  parameter  ypos may be an integer or one of the pre-de-
                fined values LEFT, RIGHT, and CENTER.

            o   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).

            o   The  final parameter refresh is a boolean value which states
                whether the widget will get refreshed after the move.

       newCDKScroll
            creates a scroll widget and returns a pointer  to  it.   Parame-
            ters:

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

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

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

            o   spos is where the scroll bar is to be placed.  This  may  be
                one of three values:

                LEFT,
                     which  puts the scroll bar on the left of the scrolling
                     list.

                RIGHT
                     which puts the scroll bar on  the  right  side  of  the
                     list, and

                NONE which does not add a scroll bar.

            o   height and width control the height and width of the widget.

                If  you  provide a value of zero for either of the height or
                the width, the widget will be created with  the  full  width
                and  height of the screen.  If you provide a negative value,
                the widget will be created the full height  or  width  minus
                the value provided.

            o   title  is  the  string which will be displayed at the top of
                the widget.  The title can be more than one line; just  pro-
                vide a carriage return character at the line break.

            o   itemList  is  the  list  of  items  to  be  displayed in the
                scrolling list.

            o   items is the number of elements in the given list.

            o   numbers is true if you want the items in the list to have  a
                number attached to the front of the list items.

            o   highlight  specifies  the display attribute of the currently
                selected item.

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

            o   shadow is true to turn the shadow on around this widget.

            If  the  widget  could not be created then a NULL pointer is re-
            turned.

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

       setCDKScroll
            lets  the  programmer  modify  certain  elements  of an existing
            scroll widget.

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

       setCDKScrollBackgroundAttrib
            sets the background attribute of the widget.

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

       setCDKScrollBackgroundColor
            sets the background color of the widget.

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

            See cdk_display(3).

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

       setCDKScrollBoxAttribute
            sets the attribute of the box.

       setCDKScrollCurrent
            sets the index for the current item.

       setCDKScrollCurrentItem
            set the current item number in the scroller.

       setCDKScrollCurrentTop
            set the top line number of the scroller.

       setCDKScrollHighlight
            sets the attribute of the highlight bar.

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

       setCDKScrollItems
            sets the contents of the scrolling list.  The previous  contents
            of the scrolling list stored in the widget are freed.

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

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

       setCDKScrollPosition
            sets the current item in the widget to the given position.

       setCDKScrollPostProcess
            allows the user to have the widget call a function after the key
            has been applied to the widget.

            o   The parameter function is the callback function.

            o   The parameter data points to data  passed  to  the  callback
                function.

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

       setCDKScrollPreProcess
            allows  the  user to have the widget call a function after a key
            is hit and before the key is applied to the widget.

            o   The parameter function is the callback function.

            o   The parameter data points to data  passed  to  the  callback
                function.

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

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

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

       setCDKScrollVerticalChar
            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 wid-
       get.

           +----------------------------------------------------------+
           | Key               Action                                 |
           +----------------------------------------------------------+
           | Left Arrow        Shift the list left one column.        |
           | Right Arrow       Shift the list right one column.       |
           | Up Arrow          Select the previous item in the list.  |
           | Down Arrow        Select the next item in the list.      |
           +----------------------------------------------------------+
           | Prev Page                                                |
           | Ctrl-B            Scroll one page backward.              |
           | Next Page                                                |
           | Ctrl-F            Scroll one page forward.               |
           +----------------------------------------------------------+
           | 1                                                        |
           | <                                                        |
           | g                                                        |
           | Home              Move to the first element in the list. |
           +----------------------------------------------------------+
           | >                                                        |
           | G                                                        |
           | End               Move to the last element in the list.  |
           +----------------------------------------------------------+
           | $                 Shift the list to the far right.       |
           | |                 Shift the list to the far left.        |
           +----------------------------------------------------------+
           | Return            Exit the widget and return  the  index |
           |                   of  the  selected  item.  Also set the |
           |                   widget data exitType to vNORMAL.       |
           | Tab               Exit the widget and return  the  index |
           |                   of  the  selected  item.  Also set the |
           |                   widget data exitType to vNORMAL.       |
           | Escape            Exit the widget and return  -1.   Also |
           |                   set   the   widget  data  exitType  to |
           |                   vESCAPE_HIT.                           |
           | Ctrl-L            Refreshes the screen.                  |
           +----------------------------------------------------------+

SEE ALSO

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

                                 2025-01-14                    cdk_scroll(3)