From 1813e9f5f6b71cf6a9b5d2b348f688df247e25d0 Mon Sep 17 00:00:00 2001
From: Nathan Hourt <nat.hourt@gmail.com>
Date: Tue, 14 Jul 2015 16:08:54 -0400
Subject: [PATCH] [GUI] Fix crash from user-after-free

The QML engine was taking ownership of Account objects, and garbage
collecting them when it was done with them, thus causing a crash when
the C++ accessed them. Fix by explicitly marking Account objects as
being owned by the C++ so QML doesn't garbage collect them.
---
 programs/light_client/ClientDataModel.cpp   |  2 ++
 programs/light_client/qml/AccountPicker.qml | 18 ++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/programs/light_client/ClientDataModel.cpp b/programs/light_client/ClientDataModel.cpp
index 3c48fee4..f76267d2 100644
--- a/programs/light_client/ClientDataModel.cpp
+++ b/programs/light_client/ClientDataModel.cpp
@@ -17,6 +17,7 @@ Account* ChainDataModel::getAccount(ObjectId id)
    if( itr == by_id_idx.end() )
    {
       auto tmp = new Account;
+      QQmlEngine::setObjectOwnership(tmp, QQmlEngine::CppOwnership);
       tmp->id = id; --m_account_query_num;
       tmp->name = QString::number( --m_account_query_num);
       auto result = m_accounts.insert( tmp );
@@ -67,6 +68,7 @@ Account* ChainDataModel::getAccount(QString name)
    if( itr == by_name_idx.end() )
    {
       auto tmp = new Account;
+      QQmlEngine::setObjectOwnership(tmp, QQmlEngine::CppOwnership);
       tmp->id = --m_account_query_num;
       tmp->name = name;
       auto result = m_accounts.insert( tmp );
diff --git a/programs/light_client/qml/AccountPicker.qml b/programs/light_client/qml/AccountPicker.qml
index b148f64f..d94549ad 100644
--- a/programs/light_client/qml/AccountPicker.qml
+++ b/programs/light_client/qml/AccountPicker.qml
@@ -49,6 +49,24 @@ RowLayout {
                                                                   : account.id)
                })
          }
+
+         Behavior on text {
+            SequentialAnimation {
+               PropertyAnimation {
+                  target: accountDetails
+                  property: "opacity"
+                  from: 1; to: 0
+                  duration: 100
+               }
+               PropertyAction { target: accountDetails; property: "text" }
+               PropertyAnimation {
+                  target: accountDetails
+                  property: "opacity"
+                  from: 0; to: 1
+                  duration: 100
+               }
+            }
+         }
       }
    }
 }