Somewhat experimental fix to try to stop the editor window jumping around on small screens.

git-svn-id: svn://localhost/ardour2/branches/3.0@8412 d708f5d6-7413-0410-9779-e7cbd77b26cf

3 files changed, 63 insertions, 0 deletions

diff --git a/libs/gtkmm2ext/gtkmm2ext/trimming_bin.h b/libs/gtkmm2ext/gtkmm2ext/trimming_bin.h
new file mode 100644
index 0000000000..4566d71cba
--- /dev/null
+++ b/libs/gtkmm2ext/gtkmm2ext/trimming_bin.h
@@ -0,0 +1,24 @@
+#include <gtkmm/scrolledwindow.h>
+
+namespace Gtkmm2ext {
+
+/** A somewhat specialised adaption of Gtk::ScrolledWindow which is the same,
+ *  except that the scrollbars are never visible.  It is useful for long toolbars
+ *  which may not fit horizontally on smaller screens; it lets them extend off the
+ *  right-hand side of the screen without causing the parent window to jump around.
+ *
+ *  It is not the same as a Gtk::ScrolledWindow with policies to never display
+ *  scrollbars, as these do not behave as we require in this case.
+ *
+ *  It is hard-wired to perform as if it were a Gtk::ScrolledWindow with a
+ *  vertical scrollbar policy of POLICY_NEVER and a horizontal policy of
+ *  POLICY_AUTOMATIC.  This could be generalised.
+ */
+class TrimmingBin : public Gtk::ScrolledWindow
+{
+public:
+	void on_size_request (Gtk::Requisition *);
+	void on_size_allocate (Gtk::Allocation &);
+};
+	
+}
diff --git a/libs/gtkmm2ext/trimming_bin.cc b/libs/gtkmm2ext/trimming_bin.cc
new file mode 100644
index 0000000000..0aba116870
--- /dev/null
+++ b/libs/gtkmm2ext/trimming_bin.cc
@@ -0,0 +1,38 @@
+#include <iostream>
+#include "gtkmm2ext/trimming_bin.h"
+
+using namespace std;
+using namespace Gtkmm2ext;
+
+void
+TrimmingBin::on_size_request (Gtk::Requisition* r)
+{
+	Gtk::ScrolledWindow::on_size_request (r);
+
+	/* Munge the height request so that it is that of the child;
+	   the Gtk::ScrolledWindow's request may include space for
+	   a horizontal scrollbar, which we will never show.
+	*/
+
+	Gtk::Widget* c = get_child ();
+	if (c && c->is_visible ()) {
+		Gtk::Requisition cr;
+		c->size_request (cr);
+		r->height = cr.height;
+	}
+}
+
+void
+TrimmingBin::on_size_allocate (Gtk::Allocation& a)
+{
+	/* We replace Gtk::ScrolledWindow's on_size_allocate with this
+	   which accepts what we are given and forces the child to use
+	   the same allocation (which may result in it being shrunk).
+	*/
+	
+	set_allocation (a);
+	Widget* c = get_child ();
+	if (c && c->is_visible ()) {
+		c->size_allocate (a);
+	}
+}
diff --git a/libs/gtkmm2ext/wscript b/libs/gtkmm2ext/wscript
index 0425b66149..40896ac3ad 100644
--- a/libs/gtkmm2ext/wscript
+++ b/libs/gtkmm2ext/wscript
@@ -51,6 +51,7 @@ gtkmm2ext_sources = [
 	'tearoff.cc',
 	'textviewer.cc',
         'treeutils.cc',
+	'trimming_bin.cc',
 	'utils.cc',
 	'version.cc',
 	'window_title.cc'