From 944b0ae55dd89e48bf8845c6d5e08a73bd1c4917 Mon Sep 17 00:00:00 2001
From: Richard Kimberly Heck <rikiheck@lyx.org>
Date: Fri, 4 May 2018 13:05:36 -0400
Subject: [PATCH] Update the Advanced F&R document class when switching
 buffers.

---
 src/frontends/qt4/FindAndReplace.cpp | 15 +++++++++++++--
 src/frontends/qt4/FindAndReplace.h   |  2 ++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/src/frontends/qt4/FindAndReplace.cpp b/src/frontends/qt4/FindAndReplace.cpp
index a0d95684b2..96fcd588bd 100644
--- a/src/frontends/qt4/FindAndReplace.cpp
+++ b/src/frontends/qt4/FindAndReplace.cpp
@@ -67,6 +67,8 @@ FindAndReplaceWidget::FindAndReplaceWidget(GuiView & view)
 	// We don't want two cursors blinking.
 	find_work_area_->stopBlinkingCaret();
 	replace_work_area_->stopBlinkingCaret();
+	old_buffer_ = view_.documentBufferView() ? 
+	    &(view_.documentBufferView()->buffer()) : 0;
 }
 
 
@@ -605,8 +607,17 @@ bool FindAndReplace::initialiseParams(std::string const & params)
 
 void FindAndReplaceWidget::updateGUI()
 {
-	bool replace_enabled = view_.documentBufferView()
-		&& !view_.documentBufferView()->buffer().isReadonly();
+	BufferView * bv = view_.documentBufferView();
+	if (bv) {
+		if (old_buffer_ != &bv->buffer()) {
+				copy_params(*bv, find_work_area_->bufferView());
+				copy_params(*bv, replace_work_area_->bufferView());
+				old_buffer_ = &bv->buffer();
+		}
+	} else
+		old_buffer_ = 0;
+
+	bool const replace_enabled = bv && !bv->buffer().isReadonly();
 	replace_work_area_->setEnabled(replace_enabled);
 	replacePB->setEnabled(replace_enabled);
 	replaceallPB->setEnabled(replace_enabled);
diff --git a/src/frontends/qt4/FindAndReplace.h b/src/frontends/qt4/FindAndReplace.h
index 93af535702..da854da7b7 100644
--- a/src/frontends/qt4/FindAndReplace.h
+++ b/src/frontends/qt4/FindAndReplace.h
@@ -40,6 +40,8 @@ public Q_SLOTS:
 private:
 	///
 	GuiView & view_;
+	///
+	Buffer * old_buffer_;
 
 	/// add a string to the combo if needed
 	void remember(std::string const & find, QComboBox & combo);