Deprecate QJsonDocument methods for converting to/from JSON binary

Also remove the example code for deprecated methods and use CBOR instead
where it makes sense.

Task-number: QTBUG-81068
Change-Id: Iffb7a4b3d7b16a1e485fc05b3ab2e2468e9e0718
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

2 files changed, 10 insertions, 9 deletions

diff --git a/examples/corelib/serialization/savegame/doc/src/savegame.qdoc b/examples/corelib/serialization/savegame/doc/src/savegame.qdoc
index a35f763430..e20cb6bc6c 100644
--- a/examples/corelib/serialization/savegame/doc/src/savegame.qdoc
+++ b/examples/corelib/serialization/savegame/doc/src/savegame.qdoc
@@ -37,8 +37,8 @@
     game generally involves serializing each game object's member variables
     to a file. Many formats can be used for this purpose, one of which is JSON.
     With QJsonDocument, you also have the ability to serialize a document in a
-    binary format, which is great if you don't want the save file to be
-    readable, or if you need to keep the file size down.
+    \l {https://tools.ietf.org/html/rfc7049} {CBOR} format, which is great if you
+    don't want the save file to be readable, or if you need to keep the file size down.
 
     In this example, we'll demonstrate how to save and load a simple game to
     and from JSON and binary formats.
@@ -133,7 +133,7 @@
 
     When loading a saved game in loadGame(), the first thing we do is open the
     save file based on which format it was saved to; \c "save.json" for JSON,
-    and \c "save.dat" for binary. We print a warning and return \c false if the
+    and \c "save.dat" for CBOR. We print a warning and return \c false if the
     file couldn't be opened.
 
     Since QJsonDocument's \l{QJsonDocument::fromJson()}{fromJson()} and
@@ -172,7 +172,7 @@
     \snippet serialization/savegame/main.cpp 1
 
     When the player has finished, we save their game. For demonstration
-    purposes, we can serialize to either JSON or binary. You can examine the
+    purposes, we can serialize to either JSON or CBOR. You can examine the
     contents of the files in the same directory as the executable (or re-run
     the example, making sure to also specify the "load" option), although the
     binary save file will contain some garbage characters (which is normal).
diff --git a/examples/corelib/serialization/savegame/game.cpp b/examples/corelib/serialization/savegame/game.cpp
index c39362bc68..58fc087b1f 100644
--- a/examples/corelib/serialization/savegame/game.cpp
+++ b/examples/corelib/serialization/savegame/game.cpp
@@ -50,6 +50,8 @@
 
 #include "game.h"
 
+#include <QCborMap>
+#include <QCborValue>
 #include <QFile>
 #include <QJsonArray>
 #include <QJsonDocument>
@@ -122,14 +124,14 @@ bool Game::loadGame(Game::SaveFormat saveFormat)
 
     QJsonDocument loadDoc(saveFormat == Json
         ? QJsonDocument::fromJson(saveData)
-        : QJsonDocument::fromBinaryData(saveData));
+        : QJsonDocument(QCborValue::fromCbor(saveData).toMap().toJsonObject()));
 
     read(loadDoc.object());
 
     QTextStream(stdout) << "Loaded save for "
                         << loadDoc["player"]["name"].toString()
                         << " using "
-                        << (saveFormat != Json ? "binary " : "") << "JSON...\n";
+                        << (saveFormat != Json ? "CBOR" : "JSON") << "...\n";
     return true;
 }
 //! [3]
@@ -148,10 +150,9 @@ bool Game::saveGame(Game::SaveFormat saveFormat) const
 
     QJsonObject gameObject;
     write(gameObject);
-    QJsonDocument saveDoc(gameObject);
     saveFile.write(saveFormat == Json
-        ? saveDoc.toJson()
-        : saveDoc.toBinaryData());
+        ? QJsonDocument(gameObject).toJson()
+        : QCborValue::fromJsonValue(gameObject).toCbor());
 
     return true;
 }