Scroll to navigation

cdk_scroll(3) Library Functions Manual cdk_scroll(3)

NAME

cdk_scroll - curses scrolling list widget.

SYNOPSIS

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

#include <cdk.h>

CDKSCROLL *scroll,
chtype * actions);
CDKSCROLL *scroll,
const char *item);
CDKSCROLL *scroll,
int position);
CDKSCROLL *scroll);
CDKSCROLL *scroll,
boolean box);
CDKSCROLL *scroll);
CDKSCROLL *scroll);
CDKSCROLL *scroll);
CDKSCROLL *widget);
CDKSCROLL *scroll,
chtype highlight);
CDKSCROLL *widget);
CDKSCROLL *scroll,
char **itemList);
CDKSCROLL *scroll,
chtype input);
CDKSCROLL *scroll,
const char *item);
CDKSCROLL *scroll,
int xpos,
int ypos,
boolean relative,
boolean refresh);
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);
CDKSCROLL *scroll);
CDKSCROLL *scroll,
CDK_CONST char **itemList,
int items,
boolean numbers,
chtype highlight,
boolean box);
CDKSCROLL *scroll,
chtype attribute);
CDKSCROLL *scroll,
const char * color);
CDKSCROLL *scroll,
boolean box);
CDKSCROLL *scroll,
chtype character);
CDKSCROLL *scroll,
intitem);
CDKSCROLL *widget,
intitem);
CDKSCROLL *widget);
CDKSCROLL *scroll,
chtype highlight);
CDKSCROLL *scroll,
chtype character);
CDKSCROLL *scroll,
CDK_CONST char **itemList,
int listSize,
boolean numbers);
CDKSCROLL *scroll,
chtype character);
CDKSCROLL *scroll,
chtype character);
CDKSCROLL *scroll,
intitem);
CDKSCROLL *scroll,
PROCESSFN callback,
void * data);
CDKSCROLL *scroll,
PROCESSFN callback,
void * data);
CDKSCROLL *scroll,
chtype character);
CDKSCROLL *scroll,
chtype character);
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

activates the scroll widget and lets the user interact with the widget.
  • The parameter scroll points to a non-NULL scroll 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 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.
allows the user to add an item into an existing scrolling list.
  • The scroll parameter points to the scrolling list to add the item to.
  • The parameter item is a char * representing the new item to add. The item is always added to the end of the list.
allows the user to add an item into an existing scrolling list.
  • The scroll parameter points to the scrolling list to add the item to.
  • The parameter f2position is an int which specifies which element to remove.
removes the widget from the screen and frees memory the object used.
draws the scroll widget on the screen. If the box option is true, the widget is drawn with a box.
removes the widget from the screen. This does NOT destroy the widget.
returns true if the widget will be drawn with a box around it.
returns the current item's index.
returns the current item number in the scroller.
returns the attribute of the highlight bar.
returns the top line of the scroller, counting from zero.
fills the parameter itemList with the contents of the scrolling list. It returns the number of elements in the scrolling list.
injects a single character into the widget.
  • The parameter scroll points to a non-NULL scroll 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:
the function returns a value ranging from zero to one less than the number of items, representing the item selected. The widget data exitType is set to vNORMAL.
the function returns -1. The widget data exitType is set to vESCAPE_HIT.
unless modified by preprocessing, postprocessing or key bindings, the function returns -1. The widget data exitType is set to vEARLY_EXIT.
allows the user to add an item into an existing scrolling list.
  • The scroll parameter points to the scrolling list to add the item to.
  • The parameter item is a char * representing the new item to add.
The item is always added before the current item in the list.
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.
creates a scroll widget and returns a pointer to it. Parameters:
  • The screen parameter is the screen you wish this widget to be placed in.
  • 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.
  • 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.
  • spos is where the scroll bar is to be placed. This may be one of three values:
which puts the scroll bar on the left of the scrolling list.
which puts the scroll bar on the right side of the list, and
•
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.
  • title is the string which will be displayed at the top of the widget. The title can be more than one line; just provide a carriage return character at the line break.
  • itemList is the list of items to be displayed in the scrolling list.
  • items is the number of elements in the given list.
  • numbers is true if you want the items in the list to have a number attached to the front of the list items.
  • highlight specifies the display attribute of the currently selected item.
  • box is true if the widget should be drawn with a box around it.
  • shadow is true to turn the shadow on around this widget.
If the widget could not be created then a NULL pointer is returned.
allows the user to move the widget around the screen via the cursor/keypad keys. See cdk_position (3) for key bindings.
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.
sets the background attribute of the widget.
The parameter attribute is a curses attribute, e.g., A_BOLD.
sets the background color of the widget.
The parameter color is in the format of the Cdk format strings.
See cdk_display (3).
sets whether the widget will be drawn with a box around it.
sets the attribute of the box.
sets the index for the current item.
set the current item number in the scroller.
set the top line number of the scroller.
sets the attribute of the highlight bar.
sets the horizontal drawing character for the box to the given character.
sets the contents of the scrolling list.
sets the lower left hand corner of the widget's box to the given character.
sets the lower right hand corner of the widget's box to the given character.
sets the current item in the widget to the given position.
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).
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).
sets the upper left hand corner of the widget's box to the given character.
sets the upper right hand corner of the widget's box to the given character.
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
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)