selector.cpp

   1 /** @file
   2  * Selector component (click and rubberband)
   3  */
   4 /* Authors:
   5  *   Krzysztof Kosiński <tweenk.pl@gmail.com>
   6  *
   7  * Copyright (C) 2009 Authors
   8  * Released under GNU GPL, read the file 'COPYING' for more information
   9  */
  10
  11 #include "desktop.h"
  12 #include "desktop-handles.h"
  13 #include "display/sodipodi-ctrlrect.h"
  14 #include "event-context.h"
  15 #include "preferences.h"
  16 #include "ui/tool/control-point.h"
  17 #include "ui/tool/event-utils.h"
  18 #include "ui/tool/selector.h"
  19
  20 namespace Inkscape {
  21 namespace UI {
  22
  23 /** A hidden control point used for rubberbanding and selection.
  24  * It uses a clever hack: the canvas item is hidden and only receives events when fed */
  25 class SelectorPoint : public ControlPoint {
  26 public:
  27     SelectorPoint(SPDesktop *d, SPCanvasGroup *group, Selector *s)
  28         : ControlPoint(d, Geom::Point(0,0), Gtk::ANCHOR_CENTER, SP_CTRL_SHAPE_SQUARE,
  29             1, &invisible_cset, group)
  30         , _selector(s)
  31         , _cancel(false)
  32     {
  33         setVisible(false);
  34         _rubber = static_cast<CtrlRect*>(sp_canvas_item_new(sp_desktop_controls(_desktop),
  35         SP_TYPE_CTRLRECT, NULL));
  36         sp_canvas_item_hide(_rubber);
  37
  38         signal_clicked.connect(sigc::mem_fun(*this, &SelectorPoint::_clicked));
  39         signal_grabbed.connect(
  40             sigc::bind_return(
  41                 sigc::hide(
  42                     sigc::mem_fun(*this, &SelectorPoint::_grabbed)),
  43                 false));
  44         signal_dragged.connect(
  45                 sigc::hide<0>( sigc::hide(
  46                     sigc::mem_fun(*this, &SelectorPoint::_dragged))));
  47         signal_ungrabbed.connect(sigc::mem_fun(*this, &SelectorPoint::_ungrabbed));
  48     }
  49     ~SelectorPoint() {
  50         gtk_object_destroy(_rubber);
  51     }
  52     SPDesktop *desktop() { return _desktop; }
  53     bool event(GdkEvent *e) {
  54         return _eventHandler(e);
  55     }
  56
  57 protected:
  58     virtual bool _eventHandler(GdkEvent *event) {
  59         if (event->type == GDK_KEY_PRESS && shortcut_key(event->key) == GDK_Escape &&
  60             sp_canvas_item_is_visible(_rubber))
  61         {
  62             _cancel = true;
  63             sp_canvas_item_hide(_rubber);
  64             return true;
  65         }
  66         return ControlPoint::_eventHandler(event);
  67     }
  68
  69 private:
  70     bool _clicked(GdkEventButton *event) {
  71         if (event->button != 1) return false;
  72         _selector->signal_point.emit(position(), event);
  73         return true;
  74     }
  75     void _grabbed() {
  76         _cancel = false;
  77         _start = position();
  78         sp_canvas_item_show(_rubber);
  79     }
  80     void _dragged(Geom::Point &new_pos) {
  81         if (_cancel) return;
  82         Geom::Rect sel(_start, new_pos);
  83         _rubber->setRectangle(sel);
  84     }
  85     void _ungrabbed(GdkEventButton *event) {
  86         if (_cancel) return;
  87         sp_canvas_item_hide(_rubber);
  88         Geom::Rect sel(_start, position());
  89         _selector->signal_area.emit(sel, event);
  90     }
  91     CtrlRect *_rubber;
  92     Selector *_selector;
  93     Geom::Point _start;
  94     bool _cancel;
  95 };
  96
  97
  98 Selector::Selector(SPDesktop *d)
  99     : Manipulator(d)
 100     , _dragger(new SelectorPoint(d, sp_desktop_controls(d), this))
 101 {
 102     _dragger->setVisible(false);
 103 }
 104
 105 Selector::~Selector()
 106 {
 107     delete _dragger;
 108 }
 109
 110 bool Selector::event(GdkEvent *event)
 111 {
 112     switch (event->type) {
 113     case GDK_BUTTON_PRESS:
 114         _dragger->setPosition(_desktop->w2d(event_point(event->motion)));
 115         break;
 116     default: break;
 117     }
 118     return _dragger->event(event);
 119 }
 120
 121 } // namespace UI
 122 } // namespace Inkscape
 123
 124 /*
 125   Local Variables:
 126   mode:c++
 127   c-file-style:"stroustrup"
 128   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 129   indent-tabs-mode:nil
 130   fill-column:99
 131   End:
 132 */
 133 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :