skeleton for a canvas button

2025-12-15 19:16:40 +01:00 · 2024-11-05 11:52:26 -07:00 · 2024-11-05 11:52:26 -07:00 · c1ad49a411
commit c1ad49a411
parent 61f1466f50
3 changed files with 262 additions and 0 deletions
--- a/libs/canvas/button.cc
+++ b/libs/canvas/button.cc
@ -0,0 +1,192 @@
+/*
+    Copyright (C) 2017 Paul Davis
+    Author: Carl Hetherington <cth@carlh.net>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program 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 General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include <iostream>
+
+#include "canvas/button.h"
+#include "canvas/canvas.h"
+#include "canvas/debug.h"
+#include "canvas/button.h"
+#include "canvas/text.h"
+
+#include "gtkmm2ext/utils.h"
+
+using namespace std;
+using namespace ArdourCanvas;
+using namespace Gtkmm2ext;
+using namespace Cairo;
+
+Button::Button (Canvas* canvas, double w, double h, Pango::FontDescription const & font_description)
+	: Rectangle (canvas)
+	, width (w)
+	, height (h)
+	, _label (new Text (canvas))
+	, prelight (false)
+	, highlight (false)
+	, clicking (false)
+{
+	_label->set_font_description (font_description);
+	init ();
+}
+
+Button::Button (Item* parent, double w, double h, Pango::FontDescription const & font_description)
+	: Rectangle (parent)
+	, _label (new Text (this))
+	, prelight (false)
+	, highlight (false)
+	, clicking (false)
+{
+	_label->set_font_description (font_description);
+	init ();
+}
+
+
+Button::Button (Canvas* canvas, std::string const & str, Pango::FontDescription const & font_description)
+	: Rectangle (canvas)
+	, _label (new Text (canvas))
+	, prelight (false)
+	, highlight (false)
+	, clicking (false)
+{
+	_label->set_font_description (font_description);
+	_label->set (str);
+	init ();
+}
+
+Button::Button (Item* parent, std::string const & str, Pango::FontDescription const & font_description)
+	: Rectangle (parent)
+	, _label (new Text (this))
+	, prelight (false)
+	, highlight (false)
+	, clicking (false)
+{
+	_label->set_font_description (font_description);
+	_label->set (str);
+	init ();
+}
+
+void
+Button::init ()
+{
+	add (_label);
+
+	Event.connect (sigc::mem_fun (*this, &Button::event_handler));
+	_label->Event.connect (sigc::mem_fun (*this, &Button::event_handler));
+
+	Rect r = _label->bounding_box ();
+	_label->set_position (Duple ((width - r.width())/2.0, (height - r.height())/2.0));
+}
+
+void
+Button::compute_bounding_box () const
+{
+	_bounding_box = Rect (0, 0, width, height);
+
+	/* Item::bounding_box() will add children */
+
+	set_bbox_clean ();
+}
+
+#define CORNER_RADIUS 5
+
+void
+Button::set_size (double w, double h)
+{
+	width = w;
+	height = h;
+
+	set_bbox_dirty ();
+	redraw ();
+}
+
+void
+Button::set_label (std::string const & str)
+{
+	_label->set (str);
+	/* move to recenter */
+	Rect r = _label->bounding_box ();
+	_label->set_position (Duple ((width - r.width())/2.0, (height - r.height())/2.0));
+	redraw ();
+}
+
+void
+Button::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
+{
+	Rect self = item_to_window (_bounding_box, false);
+	Rect draw = self.intersection (area);
+
+	if (!draw) {
+		return;
+	}
+
+	double cr, g, b, a;
+
+	context->save ();
+	context->set_operator (OPERATOR_OVER);
+
+	/* basic (rounded) rectangle, with pattern to fill */
+	rounded_rectangle (context, self.x0 + 2.5, self.y0 + 2.5, width - 4, height - 4, CORNER_RADIUS);
+
+	if (highlight) {
+		context->set_operator (Cairo::OPERATOR_OVER);
+		context->set_source_rgba (1.0, 0.0, 0.0, .2);
+		rounded_rectangle (context, self.x0 + 2.5, self.y0 + 2.5, width - 4, height - 4, CORNER_RADIUS);
+		context->fill();
+	}
+
+	if (prelight) {
+		context->set_operator (Cairo::OPERATOR_OVER);
+		color_to_rgba (contrasting_text_color (color.color()), cr, g, b, a);
+		context->set_source_rgba (cr, g, b, 0.1);
+		rounded_rectangle (context, self.x0 + 2.5, self.y0 + 2.5, width - 4, height - 4, CORNER_RADIUS);
+		context->fill();
+	}
+
+	context->restore ();
+
+	Item::render_children (area, context);
+}
+
+void
+Button::set_highlight (bool yn)
+{
+	if (highlight != yn) {
+		highlight = yn;
+		redraw ();
+	}
+}
+
+bool
+Button::event_handler (GdkEvent *ev)
+{
+	if (ev->type == GDK_ENTER_NOTIFY) {
+		prelight = true;
+		redraw ();
+	} else if (ev->type == GDK_LEAVE_NOTIFY) {
+		prelight = false;
+		redraw ();
+	}
+	return false;
+}
+
+std::string
+Button::label() const
+{
+	return _label->text();
+}