2 Copyright (C) 2009 Paul Davis
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 #ifndef __gtk2_ardour_cairo_widget_h__
21 #define __gtk2_ardour_cairo_widget_h__
23 #include <cairomm/surface.h>
24 #include <gtkmm/eventbox.h>
26 #include "gtkmm2ext/visibility.h"
27 #include "gtkmm2ext/widget_state.h"
29 /** A parent class for widgets that are rendered using Cairo.
32 class LIBGTKMM2EXT_API CairoWidget : public Gtk::EventBox
36 virtual ~CairoWidget ();
38 void set_canvas_widget ();
40 /* swizzle Gtk::Widget methods for Canvas::Widget */
43 int get_width () const;
44 int get_height () const;
45 void size_allocate (Gtk::Allocation&);
47 void set_dirty (cairo_rectangle_t *area = 0);
49 Gtkmm2ext::ActiveState active_state() const { return _active_state; }
50 Gtkmm2ext::VisualState visual_state() const { return _visual_state; }
52 /* derived widgets can override these two to catch
53 changes in active & visual state
56 virtual void set_active_state (Gtkmm2ext::ActiveState);
57 virtual void set_visual_state (Gtkmm2ext::VisualState);
59 void unset_active_state () { set_active_state (Gtkmm2ext::Off); }
60 void unset_visual_state () { set_visual_state (Gtkmm2ext::NoVisualState); }
62 /* this is an API simplification for widgets
63 that only use the Active and Normal active states.
65 void set_active (bool);
66 bool get_active () const { return active_state() != Gtkmm2ext::Off; }
68 /* widgets can be told to only draw their "foreground, and thus leave
69 in place whatever background is drawn by their parent. the default
70 is that the widget will fill its event window with the background
71 color of the parent container.
74 void set_draw_background (bool yn);
76 sigc::signal<void> StateChanged;
77 sigc::signal<bool> QueueDraw;
78 sigc::signal<bool> QueueResize;
80 static void provide_background_for_cairo_widget (Gtk::Widget& w, const Gdk::Color& bg);
82 virtual void render (cairo_t *, cairo_rectangle_t*) = 0;
84 static void set_flat_buttons (bool yn);
85 static bool flat_buttons() { return _flat_buttons; }
87 static void set_widget_prelight (bool yn);
88 static bool widget_prelight() { return _widget_prelight; }
90 static void set_source_rgb_a( cairo_t* cr, Gdk::Color, float a=1.0 );
92 /* set_focus_handler() will cause all button-press events on any
93 CairoWidget to invoke this slot/functor/function/method/callback.
95 We do this because in general, CairoWidgets do not grab
96 keyboard focus, but a button press on them should
97 clear focus from any active text entry.
99 This is global to all CairoWidgets and derived types.
101 However, derived types can override the behaviour by defining their
102 own on_button_press_event() handler which returns true under all
103 conditions (which will block this handler from being called). If
104 they wish to invoke any existing focus handler from their own
105 button press handler, they can just use: focus_handler();
107 static void set_focus_handler (sigc::slot<void,Gtk::Widget*>);
110 /** Render the widget to the given Cairo context */
111 virtual bool on_expose_event (GdkEventExpose *);
112 void on_size_allocate (Gtk::Allocation &);
113 void on_state_changed (Gtk::StateType);
114 void on_style_changed (const Glib::RefPtr<Gtk::Style>&);
115 bool on_button_press_event (GdkEventButton*);
116 Gdk::Color get_parent_bg ();
118 /* this is an additional virtual "on_..." method. Glibmm does not
119 provide a direct signal for name changes, so this acts as a proxy.
122 virtual void on_name_changed () {};
124 Gtkmm2ext::ActiveState _active_state;
125 Gtkmm2ext::VisualState _visual_state;
128 static bool _flat_buttons;
129 static bool _widget_prelight;
132 static sigc::slot<void,Gtk::Widget*> focus_handler;
135 Cairo::RefPtr<Cairo::Surface> image_surface;
136 Glib::SignalProxyProperty _name_proxy;
137 sigc::connection _parent_style_change;
138 Widget * _current_parent;
140 Gdk::Rectangle _allocation;