From: Georg Baum <Georg.Baum@post.rwth-aachen.de>
Date: Fri, 5 Jan 2007 10:32:07 +0000 (+0000)
Subject: 	* src/frontends/qt4/GuiSelection.C
X-Git-Tag: 1.6.10~11331
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=690a630c5ec361c50be7b6c84d5f9963948a1b3c;p=lyx.git

	* src/frontends/qt4/GuiSelection.C
	(GuiSelection::haveSelection): Add a big comment what we actually do
	here, and why. It took me quite some time to figure that out.

	* src/frontends/Selection.h
	(haveSelection): Add more detailed documentation


git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@16527 a592a061-630c-0410-9148-cb99ea01b6c8
---

diff --git a/src/frontends/Selection.h b/src/frontends/Selection.h
index fd9c889734..6c7e782982 100644
--- a/src/frontends/Selection.h
+++ b/src/frontends/Selection.h
@@ -27,7 +27,15 @@ class Selection
 public:
 	virtual ~Selection() {}
 
-	/// Tell the window system whether we have a selection.
+	/**
+	 * Tell the window system whether we set or cleared our selection.
+	 * This is a noop on systems that don't have a selection.
+	 * This should be called by the kernel whenever a selection is
+	 * created, changed or cleared.
+	 * \param own
+	 * If true: Tell that we got a valid selection.
+	 * If false: Tell that we cleared our selection.
+	 */
 	virtual void haveSelection(bool) = 0;
 	/**
 	 * Get the X selection contents.
diff --git a/src/frontends/qt4/GuiSelection.C b/src/frontends/qt4/GuiSelection.C
index 83c3dfb625..3a59d515ca 100644
--- a/src/frontends/qt4/GuiSelection.C
+++ b/src/frontends/qt4/GuiSelection.C
@@ -35,6 +35,15 @@ void GuiSelection::haveSelection(bool own)
 	if (!qApp->clipboard()->supportsSelection())
 		return;
 
+	// Tell qt that we have a selection by setting a dummy selection.
+	// We don't use the interface provided by Qt for setting the
+	// selection for performance reasons (see documentation of
+	// Selection::put()). Instead we only tell here that we have a
+	// selection by setting the selection to the empty string.
+	// The real selection is set in GuiApplication::x11EventFilter when
+	// an application actually requests it.
+	// This way calling Selection::have() is cheap and we can do it as
+	// often as we want.
 	if (own)
 		qApp->clipboard()->setText(QString(), QClipboard::Selection);
 	// We don't need to do anything if own = false, as this case is