Cancel wallet balance timer when shutdown requested

This doesn't fix any current problem, but it makes balance checking code less
fragile, and prevents use-after free travis error in next commit:
https://travis-ci.org/github/bitcoin/bitcoin/jobs/675367629#L4240

1 files changed, 9 insertions, 3 deletions

diff --git a/src/qt/walletmodel.cpp b/src/qt/walletmodel.cpp
index e7581cd64e..e751f402cf 100644
--- a/src/qt/walletmodel.cpp
+++ b/src/qt/walletmodel.cpp
@@ -38,14 +38,15 @@
 WalletModel::WalletModel(std::unique_ptr<interfaces::Wallet> wallet, ClientModel& client_model, const PlatformStyle *platformStyle, QObject *parent) :
     QObject(parent),
     m_wallet(std::move(wallet)),
-    m_client_model(client_model),
+    m_client_model(&client_model),
     m_node(client_model.node()),
     optionsModel(client_model.getOptionsModel()),
     addressTableModel(nullptr),
     transactionTableModel(nullptr),
     recentRequestsTableModel(nullptr),
     cachedEncryptionStatus(Unencrypted),
-    cachedNumBlocks(0)
+    cachedNumBlocks(0),
+    timer(new QTimer(this))
 {
     fHaveWatchOnly = m_wallet->haveWatchOnly();
     addressTableModel = new AddressTableModel(this);
@@ -63,11 +64,16 @@ WalletModel::~WalletModel()
 void WalletModel::startPollBalance()
 {
     // This timer will be fired repeatedly to update the balance
-    QTimer* timer = new QTimer(this);
     connect(timer, &QTimer::timeout, this, &WalletModel::pollBalanceChanged);
     timer->start(MODEL_UPDATE_DELAY);
 }
 
+void WalletModel::setClientModel(ClientModel* client_model)
+{
+    m_client_model = client_model;
+    if (!m_client_model) timer->stop();
+}
+
 void WalletModel::updateStatus()
 {
     EncryptionStatus newEncryptionStatus = getEncryptionStatus();