nick black



notcurses_selector - high level widget for selecting from a set


#include <notcurses/notcurses.h>

struct ncplane;
struct notcurses;
struct ncselector;

struct ncselector_item {
  const char* option;
  const char* desc;

typedef struct ncselector_options {
  const char* title; // title may be NULL, inhibiting riser
  const char* secondary; // secondary may be NULL
  const char* footer; // footer may be NULL
  struct ncselector_item* items; // initial items and descriptions
  // default item (selected at start)
  unsigned defidx;
  // maximum number of options to display at once
  unsigned maxdisplay;
  // exhaustive styling options
  uint64_t opchannels;   // option channels
  uint64_t descchannels; // description channels
  uint64_t titlechannels;// title channels
  uint64_t footchannels; // secondary and footer channels
  uint64_t boxchannels;  // border channels
  uint64_t flags;        // bitfield over NCSELECTOR_OPTION_*
} ncselector_options;

struct ncselector* ncselector_create(struct ncplane* n, const ncselector_options* opts);

int ncselector_additem(struct ncselector* n, const struct ncselector_item* item);

int ncselector_delitem(struct ncselector* n, const char* item);

const char* ncselector_selected(const struct ncselector* n);

struct ncplane* ncselector_plane(struct ncselector* n);

const char* ncselector_previtem(struct ncselector* n);

const char* ncselector_nextitem(struct ncselector* n);

bool ncselector_offer_input(struct ncselector* n, const ncinput* nc);

void ncselector_destroy(struct ncselector* n, char item);**


A selector widget presents a list of items (possibly more than can be displayed at once). It facilitates a choice of zero or one item from the list.


The ncplane n provided to ncselector_create must not be NULL. It will be freely resized by the new ncselector, and thus cannot be the standard plane. ncselector_selected returns the currently-selected option. ncselector_additem and ncselector_delitem allow items to be added and deleted on the fly (a static set of items can all be provided in the ncselector_create call). The backing plane will be resized as necessary for item changes.

ncselector_nextitem and ncselector_previtem select the next (down) or previous (up) option, scrolling if necessary. It is safe to call these functions even if no options are present.

ncselector_plane will return the ncplane on which the widget is drawn.

While the ncselector can be driven entirely by client code, input can be run through ncselector_offer_input to take advantage of common controls. It will handle the up and down arrows, along with PageUp and PageDown. If the mouse is enabled, the mouse scrollwheel and mouse clicks on the scroll arrows will be handled.

ncselector_destroy destroys the backing ncplane, as does ncselector_create in the event of any error.

As no flags exist, the flags option ought always be 0.


ncselector_create returns NULL on an error, in which case the passed ncplane is destroyed.

ncselector_selected returns a reference to the option part of the selected ncselector_item. If there are no items, it returns NULL.

ncselector_previtem and ncselector_nextitem return references to the option part of the newly-selected ncselector_item. If there are no items, they return NULL.


notcurses(3), notcurses_input(3), notcurses_multiselector(3), notcurses_plane(3), notcurses_stdplane(3)