[education/rkward] rkward/dataeditor: Fix crash on closing newly created data.frame

[Thomas Friedrichsmeier]

Git commit e765e978acc9b1c9c364896e49a6d6874b122924 by Thomas Friedrichsmeier.
Committed on 13/04/2022 at 20:19.
Pushed by tfry into branch 'master'.

Fix crash on closing newly created data.frame

M  +2    -1    rkward/dataeditor/rkeditordataframe.cpp

https://invent.kde.org/education/rkward/commit/e765e978acc9b1c9c364896e49a6d6874b122924

diff --git a/rkward/dataeditor/rkeditordataframe.cpp b/rkward/dataeditor/rkeditordataframe.cpp
index 16700901..2d16a51a 100644
--- a/rkward/dataeditor/rkeditordataframe.cpp
+++ b/rkward/dataeditor/rkeditordataframe.cpp
@@ -62,6 +62,7 @@ RKEditorDataFrame::RKEditorDataFrame (const QString& new_object_name, QWidget* p
 	connect (model, &RKVarEditDataFrameModel::modelObjectDestroyed, this, &RKEditorDataFrame::deleteLater);
 
 	RKGlobals::rInterface ()->closeChain (open_chain);
+	open_chain = nullptr;
 }
 
 void RKEditorDataFrame::commonInit () {
@@ -107,7 +108,7 @@ void RKEditorDataFrame::rCommandDone (RCommand *command) {
 
 	if (command->getFlags () == LOAD_COMPLETE_COMMAND) {
 		RKGlobals::rInterface ()->closeChain (open_chain);
-		open_chain = 0;
+		open_chain = nullptr;
 
 		enableEditing (true);
 	}