src/Fl_Tabs.cxx

   1 //
   2 // "$Id: Fl_Tabs.cxx 8658 2011-05-12 15:53:59Z manolo $"
   3 //
   4 // Tab widget for the Fast Light Tool Kit (FLTK).
   5 //
   6 // Copyright 1998-2010 by Bill Spitzak and others.
   7 //
   8 // This library is free software; you can redistribute it and/or
   9 // modify it under the terms of the GNU Library General Public
  10 // License as published by the Free Software Foundation; either
  11 // version 2 of the License, or (at your option) any later version.
  12 //
  13 // This library is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 // Library General Public License for more details.
  17 //
  18 // You should have received a copy of the GNU Library General Public
  19 // License along with this library; if not, write to the Free Software
  20 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  21 // USA.
  22 //
  23 // Please report all bugs and problems on the following page:
  24 //
  25 //     http://www.fltk.org/str.php
  26 //
  27
  28
  29 // This is the "file card tabs" interface to allow you to put lots and lots
  30 // of buttons and switches in a panel, as popularized by many toolkits.
  31
  32 // Each child widget is a card, and its label() is printed on the card tab.
  33 // Clicking the tab makes that card visible.
  34
  35 #include <stdio.h>
  36 #include <FL/Fl.H>
  37 #include <FL/Fl_Tabs.H>
  38 #include <FL/fl_draw.H>
  39 #include <FL/Fl_Tooltip.H>
  40
  41 #define BORDER 2
  42 #define EXTRASPACE 10
  43 #define SELECTION_BORDER 5
  44
  45 // Return the left edges of each tab (plus a fake left edge for a tab
  46 // past the right-hand one).  These positions are actually of the left
  47 // edge of the slope.  They are either separated by the correct distance
  48 // or by EXTRASPACE or by zero.
  49 // These positions are updated in the private arrays tab_pos[] and
  50 // tab_width[], resp.. If needed, these arrays are (re)allocated.
  51 // Return value is the index of the selected item.
  52
  53 int Fl_Tabs::tab_positions() {
  54   int nc = children();
  55   if (nc != tab_count) {
  56     clear_tab_positions();
  57     if (nc) {
  58       tab_pos   = (int*)malloc((nc+1)*sizeof(int));
  59       tab_width = (int*)malloc((nc+1)*sizeof(int));
  60     }
  61     tab_count = nc;
  62   }
  63   if (nc == 0) return 0;
  64   int selected = 0;
  65   Fl_Widget*const* a = array();
  66   int i;
  67   char prev_draw_shortcut = fl_draw_shortcut;
  68   fl_draw_shortcut = 1;
  69
  70   tab_pos[0] = Fl::box_dx(box());
  71   for (i=0; i<nc; i++) {
  72     Fl_Widget* o = *a++;
  73     if (o->visible()) selected = i;
  74
  75     int wt = 0; int ht = 0;
  76     o->measure_label(wt,ht);
  77
  78     tab_width[i] = wt + EXTRASPACE;
  79     tab_pos[i+1] = tab_pos[i] + tab_width[i] + BORDER;
  80   }
  81   fl_draw_shortcut = prev_draw_shortcut;
  82
  83   int r = w();
  84   if (tab_pos[i] <= r) return selected;
  85   // uh oh, they are too big:
  86   // pack them against right edge:
  87   tab_pos[i] = r;
  88   for (i = nc; i--;) {
  89     int l = r-tab_width[i];
  90     if (tab_pos[i+1] < l) l = tab_pos[i+1];
  91     if (tab_pos[i] <= l) break;
  92     tab_pos[i] = l;
  93     r -= EXTRASPACE;
  94   }
  95   // pack them against left edge and truncate width if they still don't fit:
  96   for (i = 0; i<nc; i++) {
  97     if (tab_pos[i] >= i*EXTRASPACE) break;
  98     tab_pos[i] = i*EXTRASPACE;
  99     int W = w()-1-EXTRASPACE*(children()-i) - tab_pos[i];
 100     if (tab_width[i] > W) tab_width[i] = W;
 101   }
 102   // adjust edges according to visiblity:
 103   for (i = nc; i > selected; i--) {
 104     tab_pos[i] = tab_pos[i-1] + tab_width[i-1];
 105   }
 106   return selected;
 107 }
 108
 109 // Returns space (height) in pixels needed for tabs. Negative to put them on the bottom.
 110 // Returns full height, if children() = 0.
 111 int Fl_Tabs::tab_height() {
 112   if (children() == 0) return h();
 113   int H = h();
 114   int H2 = y();
 115   Fl_Widget*const* a = array();
 116   for (int i=children(); i--;) {
 117     Fl_Widget* o = *a++;
 118     if (o->y() < y()+H) H = o->y()-y();
 119     if (o->y()+o->h() > H2) H2 = o->y()+o->h();
 120   }
 121   H2 = y()+h()-H2;
 122   if (H2 > H) return (H2 <= 0) ? 0 : -H2;
 123   else return (H <= 0) ? 0 : H;
 124 }
 125
 126 // This is used for event handling (clicks) and by fluid to pick tabs.
 127 // Returns 0, if children() = 0, or if the event is outside of the tabs area.
 128 Fl_Widget *Fl_Tabs::which(int event_x, int event_y) {
 129   if (children() == 0) return 0;
 130   int H = tab_height();
 131   if (H < 0) {
 132     if (event_y > y()+h() || event_y < y()+h()+H) return 0;
 133   } else {
 134     if (event_y > y()+H || event_y < y()) return 0;
 135   }
 136   if (event_x < x()) return 0;
 137   Fl_Widget *ret = 0L;
 138   int nc = children();
 139   tab_positions();
 140   for (int i=0; i<nc; i++) {
 141     if (event_x < x()+tab_pos[i+1]) {
 142       ret = child(i);
 143       break;
 144     }
 145   }
 146   return ret;
 147 }
 148
 149 void Fl_Tabs::redraw_tabs()
 150 {
 151   int H = tab_height();
 152   if (H >= 0) {
 153     H += Fl::box_dy(box());
 154     damage(FL_DAMAGE_SCROLL, x(), y(), w(), H);
 155   } else {
 156     H = Fl::box_dy(box()) - H;
 157     damage(FL_DAMAGE_SCROLL, x(), y() + h() - H, w(), H);
 158   }
 159 }
 160
 161 int Fl_Tabs::handle(int event) {
 162
 163   Fl_Widget *o;
 164   int i;
 165
 166   switch (event) {
 167
 168   case FL_PUSH: {
 169     int H = tab_height();
 170     if (H >= 0) {
 171       if (Fl::event_y() > y()+H) return Fl_Group::handle(event);
 172     } else {
 173       if (Fl::event_y() < y()+h()+H) return Fl_Group::handle(event);
 174     }}
 175     /* FALLTHROUGH */
 176   case FL_DRAG:
 177   case FL_RELEASE:
 178     o = which(Fl::event_x(), Fl::event_y());
 179     if (event == FL_RELEASE) {
 180       push(0);
 181       if (o && Fl::visible_focus() && Fl::focus()!=this) {
 182         Fl::focus(this);
 183         redraw_tabs();
 184       }
 185       if (o && value(o)) {
 186         Fl_Widget_Tracker wp(o);
 187         set_changed();
 188         do_callback();
 189         if (wp.deleted()) return 1;
 190       }
 191       Fl_Tooltip::current(o);
 192     } else {
 193       push(o);
 194     }
 195     return 1;
 196   case FL_MOVE: {
 197     int ret = Fl_Group::handle(event);
 198     Fl_Widget *o = Fl_Tooltip::current(), *n = o;
 199     int H = tab_height();
 200     if ( (H>=0) && (Fl::event_y()>y()+H) )
 201       return ret;
 202     else if ( (H<0) && (Fl::event_y() < y()+h()+H) )
 203       return ret;
 204     else {
 205       n = which(Fl::event_x(), Fl::event_y());
 206       if (!n) n = this;
 207     }
 208     if (n!=o)
 209       Fl_Tooltip::enter(n);
 210     return ret; }
 211   case FL_FOCUS:
 212   case FL_UNFOCUS:
 213     if (!Fl::visible_focus()) return Fl_Group::handle(event);
 214     if (Fl::event() == FL_RELEASE ||
 215         Fl::event() == FL_SHORTCUT ||
 216         Fl::event() == FL_KEYBOARD ||
 217         Fl::event() == FL_FOCUS ||
 218         Fl::event() == FL_UNFOCUS) {
 219       redraw_tabs();
 220       if (Fl::event() == FL_FOCUS) return Fl_Group::handle(event);
 221       if (Fl::event() == FL_UNFOCUS) return 0;
 222       else return 1;
 223     } else return Fl_Group::handle(event);
 224   case FL_KEYBOARD:
 225     switch (Fl::event_key()) {
 226       case FL_Left:
 227         if (child(0)->visible()) return 0;
 228         for (i = 1; i < children(); i ++)
 229           if (child(i)->visible()) break;
 230         value(child(i - 1));
 231         set_changed();
 232         do_callback();
 233         return 1;
 234       case FL_Right:
 235         if (child(children() - 1)->visible()) return 0;
 236         for (i = 0; i < children(); i ++)
 237           if (child(i)->visible()) break;
 238         value(child(i + 1));
 239         set_changed();
 240         do_callback();
 241         return 1;
 242       case FL_Down:
 243         redraw();
 244         return Fl_Group::handle(FL_FOCUS);
 245       default:
 246         break;
 247     }
 248     return Fl_Group::handle(event);
 249   case FL_SHORTCUT:
 250     for (i = 0; i < children(); ++i) {
 251       Fl_Widget *c = child(i);
 252       if (c->test_shortcut(c->label())) {
 253         char sc = !c->visible();
 254         value(c);
 255         if (sc) set_changed();
 256         do_callback();
 257         return 1;
 258       }
 259     }
 260     return Fl_Group::handle(event);
 261   case FL_SHOW:
 262     value(); // update visibilities and fall through
 263   default:
 264     return Fl_Group::handle(event);
 265
 266   }
 267 }
 268
 269 int Fl_Tabs::push(Fl_Widget *o) {
 270   if (push_ == o) return 0;
 271   if ( (push_ && !push_->visible()) || (o && !o->visible()) )
 272     redraw_tabs();
 273   push_ = o;
 274   return 1;
 275 }
 276
 277 /**
 278    Gets the currently visible widget/tab.
 279    The value() is the first visible child (or the last child if none
 280    are visible) and this also hides any other children.
 281    This allows the tabs to be deleted, moved to other groups, and
 282    show()/hide() called without it screwing up.
 283 */
 284 Fl_Widget* Fl_Tabs::value() {
 285   Fl_Widget* v = 0;
 286   Fl_Widget*const* a = array();
 287   for (int i=children(); i--;) {
 288     Fl_Widget* o = *a++;
 289     if (v) o->hide();
 290     else if (o->visible()) v = o;
 291     else if (!i) {o->show(); v = o;}
 292   }
 293   return v;
 294 }
 295
 296 /**
 297   Sets the widget to become the current visible widget/tab.
 298   Setting the value hides all other children, and makes this one
 299   visible, if it is really a child.
 300 */
 301 int Fl_Tabs::value(Fl_Widget *newvalue) {
 302   Fl_Widget*const* a = array();
 303   int ret = 0;
 304   for (int i=children(); i--;) {
 305     Fl_Widget* o = *a++;
 306     if (o == newvalue) {
 307       if (!o->visible()) ret = 1;
 308       o->show();
 309     } else {
 310       o->hide();
 311     }
 312   }
 313   return ret;
 314 }
 315
 316 enum {LEFT, RIGHT, SELECTED};
 317
 318 void Fl_Tabs::draw() {
 319   Fl_Widget *v = value();
 320   int H = tab_height();
 321
 322   if (damage() & FL_DAMAGE_ALL) { // redraw the entire thing:
 323     Fl_Color c = v ? v->color() : color();
 324
 325     draw_box(box(), x(), y()+(H>=0?H:0), w(), h()-(H>=0?H:-H), c);
 326
 327     if (selection_color() != c) {
 328       // Draw the top or bottom SELECTION_BORDER lines of the tab pane in the
 329       // selection color so that the user knows which tab is selected...
 330       int clip_y = (H >= 0) ? y() + H : y() + h() + H - SELECTION_BORDER;
 331       fl_push_clip(x(), clip_y, w(), SELECTION_BORDER);
 332       draw_box(box(), x(), clip_y, w(), SELECTION_BORDER, selection_color());
 333       fl_pop_clip();
 334     }
 335     if (v) draw_child(*v);
 336   } else { // redraw the child
 337     if (v) update_child(*v);
 338   }
 339   if (damage() & (FL_DAMAGE_SCROLL|FL_DAMAGE_ALL)) {
 340     int nc = children();
 341     int selected = tab_positions();
 342     int i;
 343     Fl_Widget*const* a = array();
 344     for (i=0; i<selected; i++)
 345       draw_tab(x()+tab_pos[i], x()+tab_pos[i+1],
 346                tab_width[i], H, a[i], LEFT);
 347     for (i=nc-1; i > selected; i--)
 348       draw_tab(x()+tab_pos[i], x()+tab_pos[i+1],
 349                tab_width[i], H, a[i], RIGHT);
 350     if (v) {
 351       i = selected;
 352       draw_tab(x()+tab_pos[i], x()+tab_pos[i+1],
 353                tab_width[i], H, a[i], SELECTED);
 354     }
 355   }
 356 }
 357
 358 void Fl_Tabs::draw_tab(int x1, int x2, int W, int H, Fl_Widget* o, int what) {
 359   int sel = (what == SELECTED);
 360   int dh = Fl::box_dh(box());
 361   int dy = Fl::box_dy(box());
 362   char prev_draw_shortcut = fl_draw_shortcut;
 363   fl_draw_shortcut = 1;
 364
 365   Fl_Boxtype bt = (o==push_ &&!sel) ? fl_down(box()) : box();
 366
 367   // compute offsets to make selected tab look bigger
 368   int yofs = sel ? 0 : BORDER;
 369
 370   if ((x2 < x1+W) && what == RIGHT) x1 = x2 - W;
 371
 372   if (H >= 0) {
 373     if (sel) fl_push_clip(x1, y(), x2 - x1, H + dh - dy);
 374     else fl_push_clip(x1, y(), x2 - x1, H);
 375
 376     H += dh;
 377
 378     Fl_Color c = sel ? selection_color() : o->selection_color();
 379
 380     draw_box(bt, x1, y() + yofs, W, H + 10 - yofs, c);
 381
 382     // Save the previous label color
 383     Fl_Color oc = o->labelcolor();
 384
 385     // Draw the label using the current color...
 386     o->labelcolor(sel ? labelcolor() : o->labelcolor());
 387     o->draw_label(x1, y() + yofs, W, H - yofs, FL_ALIGN_CENTER);
 388
 389     // Restore the original label color...
 390     o->labelcolor(oc);
 391
 392     if (Fl::focus() == this && o->visible())
 393       draw_focus(box(), x1, y(), W, H);
 394
 395     fl_pop_clip();
 396   } else {
 397     H = -H;
 398
 399     if (sel) fl_push_clip(x1, y() + h() - H - dy, x2 - x1, H + dy);
 400     else fl_push_clip(x1, y() + h() - H, x2 - x1, H);
 401
 402     H += dh;
 403
 404     Fl_Color c = sel ? selection_color() : o->selection_color();
 405
 406     draw_box(bt, x1, y() + h() - H - 10, W, H + 10 - yofs, c);
 407
 408     // Save the previous label color
 409     Fl_Color oc = o->labelcolor();
 410
 411     // Draw the label using the current color...
 412     o->labelcolor(sel ? labelcolor() : o->labelcolor());
 413     o->draw_label(x1, y() + h() - H, W, H - yofs, FL_ALIGN_CENTER);
 414
 415     // Restore the original label color...
 416     o->labelcolor(oc);
 417
 418     if (Fl::focus() == this && o->visible())
 419       draw_focus(box(), x1, y() + h() - H, W, H);
 420
 421     fl_pop_clip();
 422   }
 423   fl_draw_shortcut = prev_draw_shortcut;
 424 }
 425
 426 /**
 427     Creates a new Fl_Tabs widget using the given position, size,
 428     and label string. The default boxtype is FL_THIN_UP_BOX.
 429
 430     Use add(Fl_Widget*) to add each child, which are usually
 431     Fl_Group widgets. The children should be sized to stay
 432     away from the top or bottom edge of the Fl_Tabs widget,
 433     which is where the tabs will be drawn.
 434
 435     All children of Fl_Tabs should have the same size and exactly fit on top of
 436     each other. They should only leave space above or below where that tabs will
 437     go, but not on the sides. If the first child of Fl_Tabs is set to
 438     "resizable()", the riders will not resize when the tabs are resized.
 439
 440     The destructor <I>also deletes all the children</I>. This
 441     allows a whole tree to be deleted at once, without having to
 442     keep a pointer to all the children in the user code. A kludge
 443     has been done so the Fl_Tabs and all of its children
 444     can be automatic (local) variables, but you must declare the
 445     Fl_Tabs widget <I>first</I> so that it is destroyed last.
 446 */
 447 Fl_Tabs::Fl_Tabs(int X,int Y,int W, int H, const char *l) :
 448   Fl_Group(X,Y,W,H,l)
 449 {
 450   box(FL_THIN_UP_BOX);
 451   push_ = 0;
 452   tab_pos = 0;
 453   tab_width = 0;
 454   tab_count = 0;
 455 }
 456
 457 Fl_Tabs::~Fl_Tabs() {
 458   clear_tab_positions();
 459 }
 460
 461 /**
 462     Returns the position and size available to be used by its children.
 463
 464     If there isn't any child yet the \p tabh parameter will be used to
 465     calculate the return values. This assumes that the children's labelsize
 466     is the same as the Fl_Tabs' labelsize and adds a small border.
 467
 468     If there are already children, the values of child(0) are returned, and
 469     \p tabh is ignored.
 470
 471     \note Children should always use the same positions and sizes.
 472
 473     \p tabh can be one of
 474     \li    0: calculate label size, tabs on top
 475     \li   -1: calculate label size, tabs on bottom
 476     \li >  0: use given \p tabh value, tabs on top (height = tabh)
 477     \li < -1: use given \p tabh value, tabs on bottom (height = -tabh)
 478
 479     \param[in]  tabh            position and optional height of tabs (see above)
 480     \param[out] rx,ry,rw,rh     (x,y,w,h) of client area for children
 481
 482     \since      FLTK 1.3.0
 483 */
 484 void Fl_Tabs::client_area(int &rx, int &ry, int &rw, int &rh, int tabh) {
 485
 486   if (children()) {                     // use existing values
 487
 488     rx = child(0)->x();
 489     ry = child(0)->y();
 490     rw = child(0)->w();
 491     rh = child(0)->h();
 492
 493   } else {                              // calculate values
 494
 495     int y_offset;
 496     int label_height = fl_height(labelfont(), labelsize()) + BORDER*2;
 497
 498     if (tabh == 0)                      // use default (at top)
 499       y_offset = label_height;
 500     else if (tabh == -1)                // use default (at bottom)
 501       y_offset = -label_height;
 502     else
 503       y_offset = tabh;                  // user given value
 504
 505     rx = x();
 506     rw = w();
 507
 508     if (y_offset >= 0) {                // labels at top
 509       ry = y() + y_offset;
 510       rh = h() - y_offset;
 511     } else {                            // labels at bottom
 512       ry = y();
 513       rh = h() + y_offset;
 514     }
 515   }
 516 }
 517
 518 void Fl_Tabs::clear_tab_positions() {
 519   if (tab_pos) {
 520     free(tab_pos);
 521     tab_pos = 0;
 522   }
 523   if (tab_width){
 524     free(tab_width);
 525     tab_width = 0;
 526   }
 527 }
 528
 529 //
 530 // End of "$Id: Fl_Tabs.cxx 8658 2011-05-12 15:53:59Z manolo $".
 531 //