1notcurses_reader(3) notcurses_reader(3)
2
6 notcurses_reader - high level widget for collecting input
7
9 #include <notcurses/notcurses.h>
10 struct ncplane;
12 struct ncreader;
13 struct notcurses;
14 #define NCREADER_OPTION_HORSCROLL 0x0001
16 #define NCREADER_OPTION_VERSCROLL 0x0002
17 #define NCREADER_OPTION_NOCMDKEYS 0x0004
18 #define NCREADER_OPTION_CURSOR 0x0008
19 typedef struct ncreader_options {
21 uint64_t tchannels; // channels used for input
22 uint32_t tattrword; // attributes used for input
23 uint64_t flags; // bitfield over NCREADER_OPTION_*
24 } ncreader_options;
25 struct ncreader* ncreader_create(struct notcurses* nc, const ncread‐
27 er_options* opts);
28 int ncreader_clear(struct ncreader* n);
30 struct ncplane* ncreader_plane(struct ncreader* n);
32 int ncreader_move_left(struct ncreader* n);
34 int ncreader_move_right(struct ncreader* n);
36 int ncreader_move_up(struct ncreader* n);
38 int ncreader_move_down(struct ncreader* n);
40 int ncreader_write_egc(struct ncreader* n, const char* egc);
42 bool ncreader_offer_input(struct ncreader* n, const ncinput* ni);
44 char* ncreader_contents(const struct ncreader* n);
46 void ncreader_destroy(struct ncreader* n, char contents);**
48
50 The ncreader widget supports free-form, multi-line input. It supports
51 navigation with the arrow keys and scrolling. While the visible por‐
52 tion of the ncreader is always the same size (defined by the provided
53 ncplane), the actual text backing this visible region can grow arbi‐
54 trarily large if scrolling is enabled.
55 The following option flags are supported:
57 • NCREADER_OPTION_HORSCROLL: The visual area will be backed by a plane
59 that can grow arbitrarily wide.
60 • NCREADER_OPTION_VERSCROLL: The visual area will be backed by a plane
62 that can grow arbitrarily high.
63 • NCREADER_OPTION_NOCMDKEYS: The typical keyboard shortcuts (see below)
65 will not be honored.
66 • NCREADER_OPTION_CURSOR: The terminal's cursor will be made visible
68 across the life of the ncreader, and its location will be managed.
69 The contents of the ncreader can be retrieved with ncreader_contents.
71 The ncreader consists of at least one ncplane (the visible editing
73 area). If the ncreader supports scrolling, it will consist of two nc‐
74 planes, one of which will be kept outside the rendering area (and will
75 thus be invisible). ncreader_plane always returns the visible plane.
76 ncreader_clear drops all input from the ncreader, restoring it to the
78 same pristine condition in which it was returned by ncreader_create.
79 Unlike most widgets' input handlers, ncreader_offer_input will consume
81 most inputs. The arrow keys navigate. Backspace consumes the EGC to
82 the left of the cursor, if one exists. Enter moves to the first column
83 of the next line (if the cursor is already on the bottom line, the
84 plane must have scrolling enabled, or the cursor will not advance,
85 though the Enter will still be consumed). Otherwise, most inputs will
86 be reproduced onto the ncreader (though see NOTES below).
87 All the ncreader's content is returned from ncreader_contents, preserv‐
89 ing whitespace.
90 "Emacs-style" keyboard shortcuts similar to those supported by read‐
92 line(3) and most shells are supported unless NCREADER_OPTION_NOCMDKEYS
93 is provided to ncreader_create.
94
96 Support for NCREADER_OPTION_VERSCROLL is not yet implemented.
97 ncreader does not buffer inputs in order to assemble EGCs from them.
99 If inputs are to be processed as EGCs (as they should), the caller
100 would need assemble the grapheme clusters. Of course, there is not yet
101 any API through which multi-codepoint EGCs could be supplied to ncread‐
102 er.
103 There is not yet any support for word-wrapping. This will likely come
105 in the future.
106
109 notcurses(3), notcurses_input(3), notcurses_plane(3), readline(3)
110
112 nick black <nickblack@linux.com>.
113 v2.4.9 notcurses_reader(3)