add ncplane_set_resizecb() #1124

NEWS.md

@@ -10,6 +10,7 @@ rearrangements of Notcurses.
     self-documenting `struct ncplane_options` argument. So long as the
     arguments to `ncplane_new()` do not have side-effects, calls can be
     mechanically translated to their `ncplane_create()` equivalents.
+  * Added `nplane_set_resize()`.
 
 * 2.0.4 (2020-11-10)
   * Fixed unit tests for non UTF-8 case, brown bagger, alas.

USAGE.md

@@ -670,6 +670,13 @@ struct ncplane* ncplane_create(struct ncplane* n, const ncplane_options* nopts);
 // and will be made a bound child of 'newparent', if 'newparent' is not NULL.
 struct ncplane* ncplane_reparent(struct ncplane* n, struct ncplane* newparent);
 
+// Replace the ncplane's existing resizecb with 'resizecb' (which may be NULL).
+void ncplane_set_resizecb(struct ncplane* n, int(*resizecb)(struct ncplane*));
+
+// Suitable for use as a 'resizecb'. This will realign the plane 'n' against its
+// parent, using the alignment specified at ncplane_create()-time.
+int ncplane_resize_realign(struct ncplane* n);
+
 // Get the plane to which the plane 'n' is bound, if any.
 struct ncplane* ncplane_parent(struct ncplane* n);
 const struct ncplane* ncplane_parent_const(const struct ncplane* n);

doc/man/man3/notcurses_plane.3.md

@@ -33,6 +33,10 @@ typedef struct ncplane_options {
 
 **struct ncplane* ncplane_reparent(struct ncplane* ***n***, struct ncplane* ***newparent***);**
 
+**int ncplane_resize_realign(struct ncplane* ***n***);**
+
+**void ncplane_set_resizecb(struct ncplane* ***n***, int(*resizecb)(struct ncplane*));**
+
 **struct ncplane* ncplane_dup(struct ncplane* ***n***, void* ***opaque***);**
 
 **int ncplane_resize(struct ncplane* ***n***, int ***keepy***, int ***keepx***, int ***keepleny***, int ***keeplenx***, int ***yoff***, int ***xoff***, int ***ylen***, int ***xlen***);**

include/notcurses/notcurses.h

@@ -1049,10 +1049,13 @@ API struct ncplane* ncplane_create(struct ncplane* n, const ncplane_options* nop
 API struct ncplane* ncplane_new(struct ncplane* n, int rows, int cols, int y, int x, void* opaque, const char* name)
   __attribute__ ((deprecated));
 
-// Suitable for use as a `resizecb`. This will realign the plane 'n' against its
+// Suitable for use as a 'resizecb'. This will realign the plane 'n' against its
 // parent, using the alignment specified at ncplane_create()-time.
 API int ncplane_resize_realign(struct ncplane* n);
 
+// Replace the ncplane's existing resizecb with 'resizecb' (which may be NULL).
+API void ncplane_set_resizecb(struct ncplane* n, int(*resizecb)(struct ncplane*));
+
 // Plane 'n' will be unbound from its parent plane, if it is currently bound,
 // and will be made a bound child of 'newparent', if 'newparent' is not NULL.
 API struct ncplane* ncplane_reparent(struct ncplane* n, struct ncplane* newparent);

src/lib/notcurses.c

@@ -2036,6 +2036,10 @@ const ncplane* ncplane_parent_const(const ncplane* n){
   return n->boundto;
 }
 
+void ncplane_set_resizecb(ncplane* n, int(*resizecb)(ncplane*)){
+  n->resizecb = resizecb;
+}
+
 int ncplane_resize_realign(ncplane* n){
   const ncplane* parent = ncplane_parent_const(n);
   if(parent == n){ // somehow got stdplane, should never get here