Backport 641ae5c7ad.

The main reason is to prepare #5348 for landing.

src/BufferView.cpp

@@ -1149,7 +1149,7 @@ bool BufferView::getStatus(FuncRequest const & cmd, FuncStatus & flag)
 		break;
 
 	case LFUN_GRAPHICS_UNIFY:
-		flag.setEnabled(cur.selection());
+		flag.setEnabled(cur.countInsetsInSelection(GRAPHICS_CODE)>1);
 		break;
 
 	case LFUN_WORD_FINDADV: {

src/Cursor.cpp

@@ -1014,6 +1014,56 @@ void Cursor::clearSelection()
 }
 
 
+int Cursor::countInsetsInSelection(InsetCode const & inset_code)
+{
+	if (!selection_)
+		return 0;
+
+	DocIterator from, to;
+	from = selectionBegin();
+	to = selectionEnd();
+
+	int count = 0;
+
+	if (!from.nextInset())      //move to closest inset
+		from.forwardInset();
+
+	while (!from.empty() && from < to) {
+		Inset * inset = from.nextInset();
+		if (!inset)
+			break;
+		if (inset->lyxCode() == inset_code)
+			count ++;
+		from.forwardInset();
+	}
+	return count;
+}
+
+
+bool Cursor::insetInSelection(InsetCode const & inset_code)
+{
+	if (!selection_)
+		return false;
+
+	DocIterator from, to;
+	from = selectionBegin();
+	to = selectionEnd();
+
+	if (!from.nextInset())      //move to closest inset
+		from.forwardInset();
+
+	while (!from.empty() && from < to) {
+		Inset * inset = from.nextInset();
+		if (!inset)
+			break;
+		if (inset->lyxCode() == inset_code)
+			return true;
+		from.forwardInset();
+	}
+	return false;
+}
+
+
 void Cursor::setTargetX(int x)
 {
 	x_target_ = x;

src/Cursor.h

@@ -186,6 +186,12 @@ public:
 	void setSelection(DocIterator const & where, int n);
 	///
 	void clearSelection();
+	/// check whether selection contains specific type of inset
+	/// returns 0 if no selection was made
+	bool insetInSelection(InsetCode const & inset);
+	/// count occurences of specific inset type in the selection
+	/// returns 0 if no selection was made
+	int countInsetsInSelection(InsetCode const & inset);
 	/// access start of selection
 	CursorSlice selBegin() const;
 	/// access end of selection