/fltk/src/Fl_Tree.cxx

//

// "$Id: Fl_Tree.cxx 7604 2010-05-12 04:59:52Z greg.ercolano $"

//



#include <stdio.h>

#include <stdlib.h>

#include <string.h>



#include <FL/Fl_Tree.H>



#define SCROLL_W 15



//////////////////////

// Fl_Tree.cxx

//////////////////////

//

// Fl_Tree -- This file is part of the Fl_Tree widget for FLTK

// Copyright (C) 2009 by Greg Ercolano.

//

// This library is free software; you can redistribute it and/or

// modify it under the terms of the GNU Library General Public

// License as published by the Free Software Foundation; either

// version 2 of the License, or (at your option) any later version.

//

// This library is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

// Library General Public License for more details.

//

// You should have received a copy of the GNU Library General Public

// License along with this library; if not, write to the Free Software

// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307

// USA.

//



// INTERNAL: scroller callback

static void scroll_cb(Fl_Widget*,void *data) {

  ((Fl_Tree*)data)->redraw();

}



// INTERNAL: Parse elements from path into an array of null terminated strings

//    Path="/aa/bb"

//    Return: arr[0]="aa", arr[1]="bb", arr[2]=0

//    Caller must: free(arr[0]); free(arr);

//

static char **parse_path(const char *path) {

  while ( *path == '/' ) path++;	// skip leading '/' 

  // First pass: identify, null terminate, and count separators

  int seps = 1;			// separator count (1: first item)

  int arrsize = 1;			// array size (1: first item)

  char *save = strdup(path);		// make copy we can modify

  char *s = save;

  while ( ( s = strchr(s, '/') ) ) {

    while ( *s == '/' ) { *s++ = 0; seps++; }

    if ( *s ) { arrsize++; }

  }

  arrsize++;				// (room for terminating NULL) 

  // Second pass: create array, save nonblank elements

  char **arr = (char**)malloc(sizeof(char*) * arrsize);

  int t = 0;

  s = save;

  while ( seps-- > 0 ) {

    if ( *s ) { arr[t++] = s; }	// skips empty fields, eg. '//'

    s += (strlen(s) + 1);

  }

  arr[t] = 0;

  return(arr);

}



// INTERNAL: Recursively descend tree hierarchy, accumulating total child count

static int find_total_children(Fl_Tree_Item *item, int count=0) {

  count++;

  for ( int t=0; t<item->children(); t++ ) {

    count = find_total_children(item->child(t), count);

  }

  return(count);

}



/// Constructor.

Fl_Tree::Fl_Tree(int X, int Y, int W, int H, const char *L) : Fl_Group(X,Y,W,H,L) { 

  _root = new Fl_Tree_Item(_prefs);

  _root->parent(0);				// we are root of tree

  _root->label("ROOT");

  _item_clicked = 0;

  box(FL_DOWN_BOX);

  color(FL_WHITE);

  when(FL_WHEN_CHANGED);

  _vscroll = new Fl_Scrollbar(0,0,0,0);	// will be resized by draw()

  _vscroll->hide();

  _vscroll->type(FL_VERTICAL);

  _vscroll->step(1);

  _vscroll->callback(scroll_cb, (void*)this);

  end();

}



/// Destructor.

Fl_Tree::~Fl_Tree() {

  if ( _root ) { delete _root; _root = 0; }

}



/// Adds a new item, given a 'menu style' path, eg: "/Parent/Child/item".

/// Any parent nodes that don't already exist are created automatically.

/// Adds the item based on the value of sortorder().

/// \returns the child item created, or 0 on error.

///

Fl_Tree_Item* Fl_Tree::add(const char *path) {

  if ( ! _root ) {					// Create root if none

    _root = new Fl_Tree_Item(_prefs);

    _root->parent(0);

    _root->label("ROOT");

  }

  char **arr = parse_path(path);

  Fl_Tree_Item *item = _root->add(_prefs, arr);

  free((void*)arr[0]);

  free((void*)arr);

  return(item);

}



/// Inserts a new item above the specified Fl_Tree_Item, with the label set to 'name'.

/// \returns the item that was added, or 0 if 'above' could not be found.

/// 

Fl_Tree_Item* Fl_Tree::insert_above(Fl_Tree_Item *above, const char *name) {

  return(above->insert_above(_prefs, name));

}



/// Insert a new item into a tree-item's children at a specified position.

/// \returns the item that was added.

Fl_Tree_Item* Fl_Tree::insert(Fl_Tree_Item *item, const char *name, int pos) {

  return(item->insert(_prefs, name, pos));

}



/// Add a new child to a tree-item.

/// \returns the item that was added.

Fl_Tree_Item* Fl_Tree::add(Fl_Tree_Item *item, const char *name) {

  return(item->add(_prefs, name));

}



/// Find the item, given a menu style path, eg: "/Parent/Child/item".

///

/// There is both a const and non-const version of this method.

/// Const version allows pure const methods to use this method 

/// to do lookups without causing compiler errors.

/// \returns the item, or 0 if not found.

///

Fl_Tree_Item *Fl_Tree::find_item(const char *path) {

  if ( ! _root ) return(0);

  char **arr = parse_path(path);

  Fl_Tree_Item *item = _root->find_item(arr);

  free((void*)arr[0]);

  free((void*)arr);

  return(item);

}



/// A const version of Fl_Tree::find_item(const char *path)

const Fl_Tree_Item *Fl_Tree::find_item(const char *path) const {

  if ( ! _root ) return(0);

  char **arr = parse_path(path);

  const Fl_Tree_Item *item = _root->find_item(arr);

  free((void*)arr[0]);

  free((void*)arr);

  return(item);

}



/// Standard FLTK draw() method, handles draws the tree widget.

void Fl_Tree::draw() {

  // Let group draw box+label but *NOT* children.

  // We handle drawing children ourselves by calling each item's draw()

  //

  Fl_Group::draw_box();

  Fl_Group::draw_label();

  if ( ! _root ) return;

  int cx = x() + Fl::box_dx(box());

  int cy = y() + Fl::box_dy(box());

  int cw = w() - Fl::box_dw(box());

  int ch = h() - Fl::box_dh(box());

  // These values are changed during drawing

  // 'Y' will be the lowest point on the tree

  int X = cx + _prefs.marginleft();

  int Y = cy + _prefs.margintop() - (_vscroll->visible() ? _vscroll->value() : 0);

  int W = cw - _prefs.marginleft();		// - _prefs.marginright();

  int Ysave = Y;

  fl_push_clip(cx,cy,cw,ch);

  {

    fl_font(_prefs.labelfont(), _prefs.labelsize());

    _root->draw(X, Y, W, this, _prefs);

  }

  fl_pop_clip();

  

  // Show vertical scrollbar?

  int ydiff = (Y+_prefs.margintop())-Ysave;		// ydiff=size of tree

  int ytoofar = (cy+ch) - Y;				// ytoofar -- scrolled beyond bottom (eg. stow)

  

  //printf("ydiff=%d ch=%d Ysave=%d ytoofar=%d value=%d\n",

  //int(ydiff),int(ch),int(Ysave),int(ytoofar), int(_vscroll->value()));

  

  if ( ytoofar > 0 ) ydiff += ytoofar;

  if ( Ysave<cy || ydiff > ch || int(_vscroll->value()) > 1 ) {

    _vscroll->visible();

    int sx = x()+w()-Fl::box_dx(box())-SCROLL_W;

    int sy = y()+Fl::box_dy(box());

    int sw = SCROLL_W;

    int sh = h()-Fl::box_dh(box());

    _vscroll->show();

    _vscroll->range(0.0,ydiff-ch);

    _vscroll->resize(sx,sy,sw,sh);

    _vscroll->slider_size(float(ch)/float(ydiff));

  } else {

    _vscroll->Fl_Slider::value(0);

    _vscroll->hide();

  }

  fl_push_clip(cx,cy,cw,ch);

  Fl_Group::draw_children();	// draws any FLTK children set via Fl_Tree::widget()

  fl_pop_clip();

}



/// Standard FLTK event handler for this widget.

int Fl_Tree::handle(int e) {

  static Fl_Tree_Item *lastselect = 0;

  int changed = 0;

  int ret = Fl_Group::handle(e);

  if ( ! _root ) return(ret);

  switch ( e ) {

    case FL_PUSH: {

      lastselect = 0;

      item_clicked(0);				// assume no item was clicked

      Fl_Tree_Item *o = _root->find_clicked(_prefs);

      if ( o ) {

        ret |= 1;				// handled

        if ( Fl::event_button() == FL_LEFT_MOUSE ) {

          // Was collapse icon clicked?

          if ( o->event_on_collapse_icon(_prefs) ) {

            o->open_toggle();

            redraw();

          }

          // Item's label clicked?

          else if ( o->event_on_label(_prefs) && 

                   (!o->widget() || !Fl::event_inside(o->widget())) &&

                   callback() &&

                   (!_vscroll->visible() || !Fl::event_inside(_vscroll)) ) {

            item_clicked(o);			// save item clicked



            // Handle selection behavior

            switch ( _prefs.selectmode() ) {

              case FL_TREE_SELECT_NONE: {	// no selection changes

                break;

              }

              case FL_TREE_SELECT_SINGLE: {

                changed = select_only(o);

                break;

              }

              case FL_TREE_SELECT_MULTI: {

                int state = Fl::event_state();

                if ( state & FL_SHIFT ) {

                  if ( ! o->is_selected() ) {

                    o->select();		// add to selection

                    changed = 1;		// changed

                  }

                } else if ( state & FL_CTRL ) {

                  changed = 1;			// changed

                  o->select_toggle();		// toggle selection state

                  lastselect = o;		// save we toggled it (prevents oscillation)

                } else {

                  changed = select_only(o);

                }

                break;

              }

            }



            if ( changed ) {

              redraw();						// make change(s) visible

              if ( when() & FL_WHEN_CHANGED ) {

                set_changed();

                do_callback((Fl_Widget*)this, user_data());	// item callback

              }

            }

          }

        }

      }

      break;

    }

    case FL_DRAG: {

      if ( Fl::event_button() != FL_LEFT_MOUSE ) break;

      Fl_Tree_Item *o = _root->find_clicked(_prefs);

      if ( o ) {

        ret |= 1;				// handled

        // Item's label clicked?

        if ( o->event_on_label(_prefs) && 

	  (!o->widget() || !Fl::event_inside(o->widget())) &&

	  callback() &&

	  (!_vscroll->visible() || !Fl::event_inside(_vscroll)) ) {

          item_clicked(o);			// save item clicked

          // Handle selection behavior

          switch ( _prefs.selectmode() ) {

            case FL_TREE_SELECT_NONE: {		// no selection changes

              break;

            }

            case FL_TREE_SELECT_SINGLE: {

              changed = select_only(o);

              break;

            }

            case FL_TREE_SELECT_MULTI: {

              int state = Fl::event_state();

              if ( state & FL_CTRL ) {

                if ( lastselect != o ) {// not already toggled from last microdrag?

                  changed = 1;	// changed

                  o->select_toggle();	// toggle selection

                  lastselect = o;	// save we toggled it (prevents oscillation)

                }

              } else {

	        if ( ! o->is_selected() ) {

                  changed = 1;		// changed

                  o->select();		// select this

	        }

              }

              break;

            }

          }

          if ( changed ) {

            redraw();			// make change(s) visible

            if ( when() & FL_WHEN_CHANGED ) {

              set_changed();

              do_callback((Fl_Widget*)this, user_data());	// item callback

            }

          }

        }

      }

      break;

    }

    case FL_RELEASE: {

      if ( Fl::event_button() == FL_LEFT_MOUSE ) {

        ret |= 1;

        if ( when() & FL_WHEN_RELEASE || ( this->changed() && (when() & FL_WHEN_CHANGED)) ) {

	  do_callback((Fl_Widget*)this, user_data());       // item callback

        }

      }

      break;

    }

  }

  return(ret);

}



/// Deselect item and all its children.

///     If item is NULL, root() is used.

///     Handles calling redraw() if anything was changed.

///     Returns count of how many items were in the 'selected' state,

///     ie. how many items were "changed".

///

///     \p docallback is an optional paramemter that can either be 0 or 1:

///

///     - 0 - the callback() is not invoked (default)

///     - 1 - the callback() is invoked once if \b any items changed state,

///           and item_clicked() will be NULL (since many items could have been changed).

//

/// \todo deselect_all()'s docallback should support '2' (invoke callback for each item changed)

///

int Fl_Tree::deselect_all(Fl_Tree_Item *item, int docallback) {

  item = item ? item : root();			// NULL? use root()

  int count = item->deselect_all();

  if ( count ) {

    redraw();					// anything changed? cause redraw

    if ( docallback == 1 )

      do_callback_for_item(0);

  }

  return(count);

}



/// Select item and all its children.

///     If item is NULL, root() is used.

///     Handles calling redraw() if anything was changed.

///     Returns count of how many items were in the 'deselected' state,

///     ie. how many items were "changed".

///

///     \p docallback is an optional paramemter that can either be 0 or 1:

///

///     - 0 - the callback() is not invoked (default)

///     - 1 - the callback() is invoked once if \b any items changed state,

///           and item_clicked() will be NULL (since many items could have been changed).

///

/// \todo select_all()'s docallback should support '2' (invoke callback for each item changed)

///

int Fl_Tree::select_all(Fl_Tree_Item *item, int docallback) {

  item = item ? item : root();			// NULL? use root()

  int count = item->select_all();

  if ( count ) {

    redraw();					// anything changed? cause redraw

    if (docallback == 1)

      do_callback_for_item(0);

  }

  return(count);

}



/// Select only this item.

///     If item is NULL, root() is used.

///     Handles calling redraw() if anything was changed.

///     Returns how many items were changed, if any.

///

///     \p docallback is an optional paramemter that can either be 0, 1 or 2:

///

///     - 0 - the callback() is not invoked (default)

///     - 1 - the callback() is invoked once if \b any items changed state,

///          and item_clicked() will be NULL (since many items could have been changed).

///     - 2 - the callback() is invoked once for \b each item that changed state,

///          and the callback() can use item_clicked() to determine the item changed.

///

int Fl_Tree::select_only(Fl_Tree_Item *selitem, int docallback) {

  selitem = selitem ? selitem : root();		// NULL? use root()

  int changed = 0;

  for ( Fl_Tree_Item *item = first(); item; item = item->next() ) {

    if ( item == selitem ) {

      if ( item->is_selected() ) continue;	// don't count if already selected

      item->select();

      ++changed;

      if ( docallback == 2 ) do_callback_for_item(item);

    } else {

      if ( item->is_selected() ) {

        item->deselect();

        ++changed;

        if ( docallback == 2 ) do_callback_for_item(item);

      }

    }

  }

  if ( changed ) {

    redraw();			// anything changed? redraw

    if ( docallback == 1 ) do_callback_for_item(0);

  }

  return(changed);

}



//

// End of "$Id: Fl_Tree.cxx 7604 2010-05-12 04:59:52Z greg.ercolano $".

//