fltk/src/Fl_Multi_Label.cxx

//
// Multi-label widget for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2023 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file.  If this
// file is missing or damaged, see the license at:
//
//     https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
//     https://www.fltk.org/bugs.php
//

// Allows two or more labels to be used on a widget (by having one of them
// be one of these it allows an infinite number!)

#include <FL/Fl.H>
#include <FL/Fl_Widget.H>
#include <FL/Fl_Menu_Item.H>
#include <FL/Fl_Multi_Label.H>

static void multi_labeltype(
    const Fl_Label* o, int x, int y, int w, int h, Fl_Align a)
{
  Fl_Multi_Label* b = (Fl_Multi_Label*)(o->value);
  Fl_Label local = *o;
  local.value = b->labela;
  local.type = b->typea;
  int W = w; int H = h; local.measure(W, H);
  local.draw(x,y,w,h,a);
  if (a & FL_ALIGN_BOTTOM) h -= H;
  else if (a & FL_ALIGN_TOP) {y += H; h -= H;}
  else if (a & FL_ALIGN_RIGHT) w -= W;
  else if (a & FL_ALIGN_LEFT) {x += W; w -= W;}
  else {int d = (h+H)/2; y += d; h -= d;}
  local.value = b->labelb;
  local.type = b->typeb;
  local.draw(x,y,w,h,a);
}

// measurement is only correct for left-to-right appending...
static void multi_measure(const Fl_Label* o, int& w, int& h) {
  Fl_Multi_Label* b = (Fl_Multi_Label*)(o->value);
  Fl_Label local = *o;
  local.value = b->labela;
  local.type = b->typea;
  local.measure(w,h);
  local.value = b->labelb;
  local.type = b->typeb;
  int W = 0; int H = 0; local.measure(W,H);
  w += W; if (H>h) h = H;
}

// used by FL_MULTI_LABEL to set up the internal table, see FL/Enumerations.H
Fl_Labeltype fl_define_FL_MULTI_LABEL() {
  Fl::set_labeltype(_FL_MULTI_LABEL, multi_labeltype, multi_measure);
  return _FL_MULTI_LABEL;
}

/**
  Associate an Fl_Multi_Label with an Fl_Widget.

  This method uses Fl_Widget::label(Fl_Labeltype, const char *) internally
  to set the \e label of the widget, i.e. it stores a \e pointer to the
  Fl_Multi_Label object (\e this).
  An existing label that has been set using Fl_Widget::copy_label() will be
  released prior to the assignment of the new label.

  This sets the type of the widget's label to \_FL_MULTI_LABEL - note the
  leading underscore ('_').

  There is no way to use a method like Fl_Widget::copy_label() that transfers
  ownership of the Fl_Multi_Label and its linked objects (images, text, and
  chained Fl_Multi_Label's) to the widget.

  The Fl_Multi_Label and all linked images, text labels, or chained Fl_Multi_Label
  objects must exist during the lifetime of the widget and will not be released
  when the widget is destroyed.

  \note The user's code is responsible for releasing the Fl_Multi_Label and
    all linked objects (images, text, chained Fl_Multi_Label's) after the
    widget has been deleted. This may cause memory leaks if Fl_Multi_Label
    is used and reassigned w/o releasing the objects assigned to it.
*/
void Fl_Multi_Label::label(Fl_Widget* o) {
  o->label(FL_MULTI_LABEL, (const char*)this); // calls fl_define_FL_MULTI_LABEL()
}

/**
  Associate an Fl_Multi_Label with an Fl_Menu_Item.

  This uses Fl_Menu_Item::label(Fl_Labeltype a, const char *b) internally to
  set the \e label and the label type of the menu item, i.e. it stores a
  \e pointer to the Fl_Multi_Label object (\e this).
  An existing label (pointer) will be overwritten.

  This sets the type of the menu item's label to \_FL_MULTI_LABEL - note the
  leading underscore ('_').

  There is no way to use a method like Fl_Widget::copy_label() that transfers
  ownership of the Fl_Multi_Label and its linked objects (images, text, and
  chained Fl_Multi_Label's) to the menu item.

  The Fl_Multi_Label and all linked images, text labels, or chained
  Fl_Multi_Label objects must exist during the lifetime of the menu and
  will not be released when the menu item is destroyed.

  \note The user's code is responsible for releasing the Fl_Multi_Label and
    all linked objects (images, text, chained Fl_Multi_Label's) after the
    menu has been deleted. This may cause memory leaks if Fl_Multi_Label
    is used and reassigned w/o releasing the objects assigned to it.

  \deprecated since 1.4.0: please use Fl_Menu_Item::label(Fl_Multi_Label *)

  \see Fl_Menu_Item::label(Fl_Multi_Label *)
*/
void Fl_Multi_Label::label(Fl_Menu_Item* o) {
  o->label(FL_MULTI_LABEL, (const char*)this); // calls fl_define_FL_MULTI_LABEL()
}