From 0bc846000565159882cb7b2a8269e0be0c945c02 Mon Sep 17 00:00:00 2001
From: Sander van Grieken <sander@outrightsolutions.nl>
Date: Thu, 12 Jan 2023 13:09:21 +0100
Subject: [PATCH] qml: don't initialize instance variables on class scope for
 non-singletons (this somehow escaped attention before, as most objects
 usually don't have multiple instances, unless multiple wallets are open at
 the same time.) Also, move all signal declarations, class constants and
 variables to the top of class definitions.

---
 electrum/gui/qml/plugins.py                |  5 +-
 electrum/gui/qml/qeaddressdetails.py       | 32 +++----
 electrum/gui/qml/qeaddresslistmodel.py     | 12 +--
 electrum/gui/qml/qebitcoin.py              |  8 +-
 electrum/gui/qml/qechanneldetails.py       |  9 +-
 electrum/gui/qml/qechannelopener.py        | 20 ++---
 electrum/gui/qml/qeconfig.py               |  4 +-
 electrum/gui/qml/qedaemon.py               | 15 ++--
 electrum/gui/qml/qefx.py                   |  8 +-
 electrum/gui/qml/qeinvoice.py              | 24 +++---
 electrum/gui/qml/qeinvoicelistmodel.py     | 10 +--
 electrum/gui/qml/qelnpaymentdetails.py     | 14 +--
 electrum/gui/qml/qenetwork.py              | 21 +++--
 electrum/gui/qml/qeqr.py                   | 19 +++--
 electrum/gui/qml/qerequestdetails.py       | 13 +--
 electrum/gui/qml/qeserverlistmodel.py      |  4 +-
 electrum/gui/qml/qeswaphelper.py           | 36 ++++----
 electrum/gui/qml/qetransactionlistmodel.py | 24 +++---
 electrum/gui/qml/qetxdetails.py            | 70 +++++++--------
 electrum/gui/qml/qetxfinalizer.py          | 99 +++++++++++-----------
 electrum/gui/qml/qewallet.py               | 27 +++---
 electrum/gui/qml/qewalletdb.py             | 16 ++--
 22 files changed, 250 insertions(+), 240 deletions(-)

diff --git a/electrum/gui/qml/plugins.py b/electrum/gui/qml/plugins.py
index a9dffbc67..cee411a10 100644
--- a/electrum/gui/qml/plugins.py
+++ b/electrum/gui/qml/plugins.py
@@ -10,10 +10,11 @@ class PluginQObject(QObject):
     busyChanged = pyqtSignal()
     pluginEnabledChanged = pyqtSignal()
 
-    _busy = False
-
     def __init__(self, plugin, parent):
         super().__init__(parent)
+
+        self._busy = False
+
         self.plugin = plugin
         self.app = parent
 
diff --git a/electrum/gui/qml/qeaddressdetails.py b/electrum/gui/qml/qeaddressdetails.py
index 5b137bc59..2d910c160 100644
--- a/electrum/gui/qml/qeaddressdetails.py
+++ b/electrum/gui/qml/qeaddressdetails.py
@@ -8,27 +8,27 @@ from .qewallet import QEWallet
 
 
 class QEAddressDetails(QObject):
-    def __init__(self, parent=None):
-        super().__init__(parent)
-
     _logger = get_logger(__name__)
 
-    _wallet = None
-    _address = None
+    detailsChanged = pyqtSignal()
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
 
-    _label = None
-    _frozen = False
-    _scriptType = None
-    _status = None
-    _balance = QEAmount()
-    _pubkeys = None
-    _privkey = None
-    _derivationPath = None
-    _numtx = 0
+        self._wallet = None
+        self._address = None
 
-    _historyModel = None
+        self._label = None
+        self._frozen = False
+        self._scriptType = None
+        self._status = None
+        self._balance = QEAmount()
+        self._pubkeys = None
+        self._privkey = None
+        self._derivationPath = None
+        self._numtx = 0
 
-    detailsChanged = pyqtSignal()
+        self._historyModel = None
 
     walletChanged = pyqtSignal()
     @pyqtProperty(QEWallet, notify=walletChanged)
diff --git a/electrum/gui/qml/qeaddresslistmodel.py b/electrum/gui/qml/qeaddresslistmodel.py
index d6f508de5..42d621109 100644
--- a/electrum/gui/qml/qeaddresslistmodel.py
+++ b/electrum/gui/qml/qeaddresslistmodel.py
@@ -13,12 +13,6 @@ if TYPE_CHECKING:
 
 
 class QEAddressListModel(QAbstractListModel):
-    def __init__(self, wallet: 'Abstract_Wallet', parent=None):
-        super().__init__(parent)
-        self.wallet = wallet
-        self.setDirty()
-        self.init_model()
-
     _logger = get_logger(__name__)
 
     # define listmodel rolemap
@@ -26,6 +20,12 @@ class QEAddressListModel(QAbstractListModel):
     _ROLE_KEYS = range(Qt.UserRole, Qt.UserRole + len(_ROLE_NAMES))
     _ROLE_MAP  = dict(zip(_ROLE_KEYS, [bytearray(x.encode()) for x in _ROLE_NAMES]))
 
+    def __init__(self, wallet: 'Abstract_Wallet', parent=None):
+        super().__init__(parent)
+        self.wallet = wallet
+        self.setDirty()
+        self.init_model()
+
     def rowCount(self, index):
         return len(self.receive_addresses) + len(self.change_addresses)
 
diff --git a/electrum/gui/qml/qebitcoin.py b/electrum/gui/qml/qebitcoin.py
index efc3684c7..4ca0f4a88 100644
--- a/electrum/gui/qml/qebitcoin.py
+++ b/electrum/gui/qml/qebitcoin.py
@@ -15,10 +15,6 @@ from electrum.mnemonic import is_any_2fa_seed_type
 from .qetypes import QEAmount
 
 class QEBitcoin(QObject):
-    def __init__(self, config, parent=None):
-        super().__init__(parent)
-        self.config = config
-
     _logger = get_logger(__name__)
 
     generatedSeedChanged = pyqtSignal()
@@ -30,6 +26,10 @@ class QEBitcoin(QObject):
     validationMessageChanged = pyqtSignal()
     _validationMessage = ''
 
+    def __init__(self, config, parent=None):
+        super().__init__(parent)
+        self.config = config
+
     @pyqtProperty('QString', notify=generatedSeedChanged)
     def generated_seed(self):
         return self.generatedSeed
diff --git a/electrum/gui/qml/qechanneldetails.py b/electrum/gui/qml/qechanneldetails.py
index f7cdf1c65..60c556c53 100644
--- a/electrum/gui/qml/qechanneldetails.py
+++ b/electrum/gui/qml/qechanneldetails.py
@@ -21,16 +21,17 @@ class QEChannelDetails(QObject, QtEventListener):
 
     Q_ENUMS(State)
 
-    _wallet = None
-    _channelid = None
-    _channel = None
-
     channelChanged = pyqtSignal()
     channelCloseSuccess = pyqtSignal()
     channelCloseFailed = pyqtSignal([str], arguments=['message'])
 
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self._wallet = None
+        self._channelid = None
+        self._channel = None
+
         self.register_callbacks()
         self.destroyed.connect(lambda: self.on_destroy())
 
diff --git a/electrum/gui/qml/qechannelopener.py b/electrum/gui/qml/qechannelopener.py
index 864b5f656..5d0e71493 100644
--- a/electrum/gui/qml/qechannelopener.py
+++ b/electrum/gui/qml/qechannelopener.py
@@ -19,18 +19,8 @@ from .qewallet import QEWallet
 
 
 class QEChannelOpener(QObject, AuthMixin):
-    def __init__(self, parent=None):
-        super().__init__(parent)
-
     _logger = get_logger(__name__)
 
-    _wallet = None
-    _nodeid = None
-    _amount = QEAmount()
-    _valid = False
-    _opentx = None
-    _txdetails = None
-
     validationError = pyqtSignal([str,str], arguments=['code','message'])
     conflictingBackup = pyqtSignal([str], arguments=['message'])
     channelOpening = pyqtSignal([str], arguments=['peer'])
@@ -39,6 +29,16 @@ class QEChannelOpener(QObject, AuthMixin):
 
     dataChanged = pyqtSignal() # generic notify signal
 
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        self._wallet = None
+        self._nodeid = None
+        self._amount = QEAmount()
+        self._valid = False
+        self._opentx = None
+        self._txdetails = None
+
     walletChanged = pyqtSignal()
     @pyqtProperty(QEWallet, notify=walletChanged)
     def wallet(self):
diff --git a/electrum/gui/qml/qeconfig.py b/electrum/gui/qml/qeconfig.py
index e8a2de2a6..99fb74dee 100644
--- a/electrum/gui/qml/qeconfig.py
+++ b/electrum/gui/qml/qeconfig.py
@@ -10,12 +10,12 @@ from .qetypes import QEAmount
 from .auth import AuthMixin, auth_protect
 
 class QEConfig(AuthMixin, QObject):
+    _logger = get_logger(__name__)
+
     def __init__(self, config, parent=None):
         super().__init__(parent)
         self.config = config
 
-    _logger = get_logger(__name__)
-
     autoConnectChanged = pyqtSignal()
     @pyqtProperty(bool, notify=autoConnectChanged)
     def autoConnect(self):
diff --git a/electrum/gui/qml/qedaemon.py b/electrum/gui/qml/qedaemon.py
index 9e0655aed..8ea470476 100644
--- a/electrum/gui/qml/qedaemon.py
+++ b/electrum/gui/qml/qedaemon.py
@@ -107,14 +107,8 @@ class QEWalletListModel(QAbstractListModel):
             i += 1
 
 class QEDaemon(AuthMixin, QObject):
-    def __init__(self, daemon, parent=None):
-        super().__init__(parent)
-        self.daemon = daemon
-        self.qefx = QEFX(daemon.fx, daemon.config)
-        self._walletdb = QEWalletDB()
-        self._walletdb.validPasswordChanged.connect(self.passwordValidityCheck)
-
     _logger = get_logger(__name__)
+
     _available_wallets = None
     _current_wallet = None
     _new_wallet_wizard = None
@@ -133,6 +127,13 @@ class QEDaemon(AuthMixin, QObject):
     walletOpenError = pyqtSignal([str], arguments=["error"])
     walletDeleteError = pyqtSignal([str,str], arguments=['code', 'message'])
 
+    def __init__(self, daemon, parent=None):
+        super().__init__(parent)
+        self.daemon = daemon
+        self.qefx = QEFX(daemon.fx, daemon.config)
+        self._walletdb = QEWalletDB()
+        self._walletdb.validPasswordChanged.connect(self.passwordValidityCheck)
+
     @pyqtSlot()
     def passwordValidityCheck(self):
         if not self._walletdb._validPassword:
diff --git a/electrum/gui/qml/qefx.py b/electrum/gui/qml/qefx.py
index 79d833aae..38847c418 100644
--- a/electrum/gui/qml/qefx.py
+++ b/electrum/gui/qml/qefx.py
@@ -12,6 +12,10 @@ from .qetypes import QEAmount
 from .util import QtEventListener, event_listener
 
 class QEFX(QObject, QtEventListener):
+    _logger = get_logger(__name__)
+
+    quotesUpdated = pyqtSignal()
+
     def __init__(self, fxthread: FxThread, config: SimpleConfig, parent=None):
         super().__init__(parent)
         self.fx = fxthread
@@ -19,10 +23,6 @@ class QEFX(QObject, QtEventListener):
         self.register_callbacks()
         self.destroyed.connect(lambda: self.on_destroy())
 
-    _logger = get_logger(__name__)
-
-    quotesUpdated = pyqtSignal()
-
     def on_destroy(self):
         self.unregister_callbacks()
 
diff --git a/electrum/gui/qml/qeinvoice.py b/electrum/gui/qml/qeinvoice.py
index 5575b7f3c..0dbae5bac 100644
--- a/electrum/gui/qml/qeinvoice.py
+++ b/electrum/gui/qml/qeinvoice.py
@@ -44,14 +44,14 @@ class QEInvoice(QObject):
 
     _logger = get_logger(__name__)
 
-    _wallet = None
-    _canSave = False
-    _canPay = False
-    _key = None
-
     def __init__(self, parent=None):
         super().__init__(parent)
 
+        self._wallet = None
+        self._canSave = False
+        self._canPay = False
+        self._key = None
+
     walletChanged = pyqtSignal()
     @pyqtProperty(QEWallet, notify=walletChanged)
     def wallet(self):
@@ -117,15 +117,8 @@ class QEInvoice(QObject):
         return self._wallet.wallet.lnworker.num_sats_can_send()
 
 class QEInvoiceParser(QEInvoice):
-
     _logger = get_logger(__name__)
 
-    _invoiceType = QEInvoice.Type.Invalid
-    _recipient = ''
-    _effectiveInvoice = None
-    _amount = QEAmount()
-    _userinfo = ''
-
     invoiceChanged = pyqtSignal()
     invoiceSaved = pyqtSignal([str], arguments=['key'])
 
@@ -140,6 +133,13 @@ class QEInvoiceParser(QEInvoice):
 
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self._invoiceType = QEInvoice.Type.Invalid
+        self._recipient = ''
+        self._effectiveInvoice = None
+        self._amount = QEAmount()
+        self._userinfo = ''
+
         self.clear()
 
     @pyqtProperty(int, notify=invoiceChanged)
diff --git a/electrum/gui/qml/qeinvoicelistmodel.py b/electrum/gui/qml/qeinvoicelistmodel.py
index dd91a435c..524bea661 100644
--- a/electrum/gui/qml/qeinvoicelistmodel.py
+++ b/electrum/gui/qml/qeinvoicelistmodel.py
@@ -13,11 +13,6 @@ from .qetypes import QEAmount
 class QEAbstractInvoiceListModel(QAbstractListModel):
     _logger = get_logger(__name__)
 
-    def __init__(self, wallet, parent=None):
-        super().__init__(parent)
-        self.wallet = wallet
-        self.init_model()
-
     # define listmodel rolemap
     _ROLE_NAMES=('key', 'is_lightning', 'timestamp', 'date', 'message', 'amount',
                  'status', 'status_str', 'address', 'expiration', 'type', 'onchain_fallback',
@@ -26,6 +21,11 @@ class QEAbstractInvoiceListModel(QAbstractListModel):
     _ROLE_MAP  = dict(zip(_ROLE_KEYS, [bytearray(x.encode()) for x in _ROLE_NAMES]))
     _ROLE_RMAP = dict(zip(_ROLE_NAMES, _ROLE_KEYS))
 
+    def __init__(self, wallet, parent=None):
+        super().__init__(parent)
+        self.wallet = wallet
+        self.init_model()
+
     def rowCount(self, index):
         return len(self.invoices)
 
diff --git a/electrum/gui/qml/qelnpaymentdetails.py b/electrum/gui/qml/qelnpaymentdetails.py
index 1bfcd2e1e..bdcfd2ef1 100644
--- a/electrum/gui/qml/qelnpaymentdetails.py
+++ b/electrum/gui/qml/qelnpaymentdetails.py
@@ -7,17 +7,17 @@ from .qetypes import QEAmount
 from .qewallet import QEWallet
 
 class QELnPaymentDetails(QObject):
-    def __init__(self, parent=None):
-        super().__init__(parent)
-
     _logger = get_logger(__name__)
 
-    _wallet = None
-    _key = None
-    _date = None
-
     detailsChanged = pyqtSignal()
 
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        self._wallet = None
+        self._key = None
+        self._date = None
+
     walletChanged = pyqtSignal()
     @pyqtProperty(QEWallet, notify=walletChanged)
     def wallet(self):
diff --git a/electrum/gui/qml/qenetwork.py b/electrum/gui/qml/qenetwork.py
index e0671bcbf..462184c14 100644
--- a/electrum/gui/qml/qenetwork.py
+++ b/electrum/gui/qml/qenetwork.py
@@ -8,17 +8,6 @@ from .util import QtEventListener, event_listener
 from .qeserverlistmodel import QEServerListModel
 
 class QENetwork(QObject, QtEventListener):
-    def __init__(self, network, qeconfig, parent=None):
-        super().__init__(parent)
-        self.network = network
-        self._qeconfig = qeconfig
-        self._serverListModel = None
-        self._height = network.get_local_height() # init here, update event can take a while
-        self.register_callbacks()
-
-        self._qeconfig.useGossipChanged.connect(self.on_gossip_setting_changed)
-
-
     _logger = get_logger(__name__)
 
     networkUpdated = pyqtSignal()
@@ -47,6 +36,16 @@ class QENetwork(QObject, QtEventListener):
     _gossipDbChannels = 0
     _gossipDbPolicies = 0
 
+    def __init__(self, network, qeconfig, parent=None):
+        super().__init__(parent)
+        self.network = network
+        self._qeconfig = qeconfig
+        self._serverListModel = None
+        self._height = network.get_local_height() # init here, update event can take a while
+        self.register_callbacks()
+
+        self._qeconfig.useGossipChanged.connect(self.on_gossip_setting_changed)
+
     @event_listener
     def on_event_network_updated(self, *args):
         self.networkUpdated.emit()
diff --git a/electrum/gui/qml/qeqr.py b/electrum/gui/qml/qeqr.py
index 3d23ecf7f..95ce090a1 100644
--- a/electrum/gui/qml/qeqr.py
+++ b/electrum/gui/qml/qeqr.py
@@ -15,21 +15,22 @@ from electrum.i18n import _
 from electrum.util import profiler, get_asyncio_loop
 
 class QEQRParser(QObject):
-    def __init__(self, text=None, parent=None):
-        super().__init__(parent)
-        self._text = text
-        self.qrreader = get_qr_reader()
-        if not self.qrreader:
-            raise Exception(_("The platform QR detection library is not available."))
-
     _logger = get_logger(__name__)
 
     busyChanged = pyqtSignal()
     dataChanged = pyqtSignal()
     imageChanged = pyqtSignal()
 
-    _busy = False
-    _image = None
+    def __init__(self, text=None, parent=None):
+        super().__init__(parent)
+
+        self._busy = False
+        self._image = None
+
+        self._text = text
+        self.qrreader = get_qr_reader()
+        if not self.qrreader:
+            raise Exception(_("The platform QR detection library is not available."))
 
     @pyqtSlot('QImage')
     def scanImage(self, image=None):
diff --git a/electrum/gui/qml/qerequestdetails.py b/electrum/gui/qml/qerequestdetails.py
index 5326aceae..59569c163 100644
--- a/electrum/gui/qml/qerequestdetails.py
+++ b/electrum/gui/qml/qerequestdetails.py
@@ -26,17 +26,18 @@ class QERequestDetails(QObject, QtEventListener):
 
     _logger = get_logger(__name__)
 
-    _wallet = None
-    _key = None
-    _req = None
-    _timer = None
-    _amount = None
-
     detailsChanged = pyqtSignal() # generic request properties changed signal
     statusChanged = pyqtSignal()
 
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self._wallet = None
+        self._key = None
+        self._req = None
+        self._timer = None
+        self._amount = None
+
         self.register_callbacks()
         self.destroyed.connect(lambda: self.on_destroy())
 
diff --git a/electrum/gui/qml/qeserverlistmodel.py b/electrum/gui/qml/qeserverlistmodel.py
index 2d32c0502..4fc315133 100644
--- a/electrum/gui/qml/qeserverlistmodel.py
+++ b/electrum/gui/qml/qeserverlistmodel.py
@@ -13,7 +13,6 @@ from .util import QtEventListener, qt_event_listener, event_listener
 
 class QEServerListModel(QAbstractListModel, QtEventListener):
     _logger = get_logger(__name__)
-    _chaintips = 0
 
     # define listmodel rolemap
     _ROLE_NAMES=('name', 'address', 'is_connected', 'is_primary', 'is_tor', 'chain', 'height')
@@ -23,6 +22,9 @@ class QEServerListModel(QAbstractListModel, QtEventListener):
 
     def __init__(self, network, parent=None):
         super().__init__(parent)
+
+        self._chaintips = 0
+
         self.network = network
         self.init_model()
         self.register_callbacks()
diff --git a/electrum/gui/qml/qeswaphelper.py b/electrum/gui/qml/qeswaphelper.py
index 1e8efafe8..5f74f7888 100644
--- a/electrum/gui/qml/qeswaphelper.py
+++ b/electrum/gui/qml/qeswaphelper.py
@@ -18,30 +18,30 @@ from .qewallet import QEWallet
 class QESwapHelper(AuthMixin, QObject):
     _logger = get_logger(__name__)
 
-    _wallet = None
-    _sliderPos = 0
-    _rangeMin = 0
-    _rangeMax = 0
-    _tx = None
-    _valid = False
-    _userinfo = ''
-    _tosend = QEAmount()
-    _toreceive = QEAmount()
-    _serverfeeperc = ''
-    _serverfee = QEAmount()
-    _miningfee = QEAmount()
-    _isReverse = False
-
-    _service_available = False
-    _send_amount = 0
-    _receive_amount = 0
-
     error = pyqtSignal([str], arguments=['message'])
     confirm = pyqtSignal([str], arguments=['message'])
 
     def __init__(self, parent=None):
         super().__init__(parent)
 
+        self._wallet = None
+        self._sliderPos = 0
+        self._rangeMin = 0
+        self._rangeMax = 0
+        self._tx = None
+        self._valid = False
+        self._userinfo = ''
+        self._tosend = QEAmount()
+        self._toreceive = QEAmount()
+        self._serverfeeperc = ''
+        self._serverfee = QEAmount()
+        self._miningfee = QEAmount()
+        self._isReverse = False
+
+        self._service_available = False
+        self._send_amount = 0
+        self._receive_amount = 0
+
     walletChanged = pyqtSignal()
     @pyqtProperty(QEWallet, notify=walletChanged)
     def wallet(self):
diff --git a/electrum/gui/qml/qetransactionlistmodel.py b/electrum/gui/qml/qetransactionlistmodel.py
index b56001cad..478a7b8c1 100644
--- a/electrum/gui/qml/qetransactionlistmodel.py
+++ b/electrum/gui/qml/qetransactionlistmodel.py
@@ -10,18 +10,6 @@ from .qetypes import QEAmount
 from .util import QtEventListener, qt_event_listener
 
 class QETransactionListModel(QAbstractListModel, QtEventListener):
-    def __init__(self, wallet, parent=None, *, onchain_domain=None, include_lightning=True):
-        super().__init__(parent)
-        self.wallet = wallet
-        self.onchain_domain = onchain_domain
-        self.include_lightning = include_lightning
-
-        self.register_callbacks()
-        self.destroyed.connect(lambda: self.on_destroy())
-        self.requestRefresh.connect(lambda: self.init_model())
-
-        self.init_model()
-
     _logger = get_logger(__name__)
 
     # define listmodel rolemap
@@ -34,6 +22,18 @@ class QETransactionListModel(QAbstractListModel, QtEventListener):
 
     requestRefresh = pyqtSignal()
 
+    def __init__(self, wallet, parent=None, *, onchain_domain=None, include_lightning=True):
+        super().__init__(parent)
+        self.wallet = wallet
+        self.onchain_domain = onchain_domain
+        self.include_lightning = include_lightning
+
+        self.register_callbacks()
+        self.destroyed.connect(lambda: self.on_destroy())
+        self.requestRefresh.connect(lambda: self.init_model())
+
+        self.init_model()
+
     def on_destroy(self):
         self.unregister_callbacks()
 
diff --git a/electrum/gui/qml/qetxdetails.py b/electrum/gui/qml/qetxdetails.py
index 2dc098256..f3520a2f3 100644
--- a/electrum/gui/qml/qetxdetails.py
+++ b/electrum/gui/qml/qetxdetails.py
@@ -12,41 +12,6 @@ from .util import QtEventListener, event_listener
 class QETxDetails(QObject, QtEventListener):
     _logger = get_logger(__name__)
 
-    _wallet = None
-    _txid = ''
-    _rawtx = ''
-    _label = ''
-
-    _tx = None
-
-    _status = ''
-    _amount = QEAmount()
-    _lnamount = QEAmount()
-    _fee = QEAmount()
-    _inputs = []
-    _outputs = []
-
-    _is_lightning_funding_tx = False
-    _can_bump = False
-    _can_dscancel = False
-    _can_broadcast = False
-    _can_cpfp = False
-    _can_save_as_local = False
-    _can_remove = False
-    _can_sign = False
-    _is_unrelated = False
-    _is_complete = False
-    _is_mined = False
-    _is_final = False
-
-    _mempool_depth = ''
-
-    _date = ''
-    _height = 0
-    _confirmations = 0
-    _txpos = -1
-    _header_hash = ''
-
     confirmRemoveLocalTx = pyqtSignal([str], arguments=['message'])
     saveTxError = pyqtSignal([str,str], arguments=['code', 'message'])
     saveTxSuccess = pyqtSignal()
@@ -58,6 +23,41 @@ class QETxDetails(QObject, QtEventListener):
         self.register_callbacks()
         self.destroyed.connect(lambda: self.on_destroy())
 
+        self._wallet = None
+        self._txid = ''
+        self._rawtx = ''
+        self._label = ''
+
+        self._tx = None
+
+        self._status = ''
+        self._amount = QEAmount()
+        self._lnamount = QEAmount()
+        self._fee = QEAmount()
+        self._inputs = []
+        self._outputs = []
+
+        self._is_lightning_funding_tx = False
+        self._can_bump = False
+        self._can_dscancel = False
+        self._can_broadcast = False
+        self._can_cpfp = False
+        self._can_save_as_local = False
+        self._can_remove = False
+        self._can_sign = False
+        self._is_unrelated = False
+        self._is_complete = False
+        self._is_mined = False
+        self._is_final = False
+
+        self._mempool_depth = ''
+
+        self._date = ''
+        self._height = 0
+        self._confirmations = 0
+        self._txpos = -1
+        self._header_hash = ''
+
     def on_destroy(self):
         self.unregister_callbacks()
 
diff --git a/electrum/gui/qml/qetxfinalizer.py b/electrum/gui/qml/qetxfinalizer.py
index 6248b1771..ac38b7640 100644
--- a/electrum/gui/qml/qetxfinalizer.py
+++ b/electrum/gui/qml/qetxfinalizer.py
@@ -16,16 +16,16 @@ from .qetypes import QEAmount
 from .util import QtEventListener, event_listener
 
 class FeeSlider(QObject):
-    _wallet = None
-    _sliderSteps = 0
-    _sliderPos = 0
-    _method = -1
-    _target = ''
-    _config = None
-
     def __init__(self, parent=None):
         super().__init__(parent)
 
+        self._wallet = None
+        self._sliderSteps = 0
+        self._sliderPos = 0
+        self._method = -1
+        self._target = ''
+        self._config = None
+
     walletChanged = pyqtSignal()
     @pyqtProperty(QEWallet, notify=walletChanged)
     def wallet(self):
@@ -125,17 +125,17 @@ class FeeSlider(QObject):
         raise NotImplementedError()
 
 class TxFeeSlider(FeeSlider):
-    _fee = QEAmount()
-    _feeRate = ''
-    _rbf = False
-    _tx = None
-    _outputs = []
-    _valid = False
-    _warning = ''
-
     def __init__(self, parent=None):
         super().__init__(parent)
 
+        self._fee = QEAmount()
+        self._feeRate = ''
+        self._rbf = False
+        self._tx = None
+        self._outputs = []
+        self._valid = False
+        self._warning = ''
+
     feeChanged = pyqtSignal()
     @pyqtProperty(QEAmount, notify=feeChanged)
     def fee(self):
@@ -223,13 +223,13 @@ class QETxFinalizer(TxFeeSlider):
         self.f_make_tx = make_tx
         self.f_accept = accept
 
-    _logger = get_logger(__name__)
+        self._address = ''
+        self._amount = QEAmount()
+        self._effectiveAmount = QEAmount()
+        self._extraFee = QEAmount()
+        self._canRbf = False
 
-    _address = ''
-    _amount = QEAmount()
-    _effectiveAmount = QEAmount()
-    _extraFee = QEAmount()
-    _canRbf = False
+    _logger = get_logger(__name__)
 
     addressChanged = pyqtSignal()
     @pyqtProperty(str, notify=addressChanged)
@@ -394,12 +394,13 @@ class QETxFinalizer(TxFeeSlider):
 # calls get_tx() once txid is set
 # calls tx_verified and emits txMined signal once tx is verified
 class TxMonMixin(QtEventListener):
-    _txid = ''
-
     txMined = pyqtSignal()
 
     def __init__(self, parent=None):
         self._logger.debug('TxMonMixin.__init__')
+
+        self._txid = ''
+
         self.register_callbacks()
         self.destroyed.connect(lambda: self.on_destroy())
 
@@ -436,14 +437,14 @@ class TxMonMixin(QtEventListener):
 class QETxRbfFeeBumper(TxFeeSlider, TxMonMixin):
     _logger = get_logger(__name__)
 
-    _oldfee = QEAmount()
-    _oldfee_rate = 0
-    _orig_tx = None
-    _rbf = True
-
     def __init__(self, parent=None):
         super().__init__(parent)
 
+        self._oldfee = QEAmount()
+        self._oldfee_rate = 0
+        self._orig_tx = None
+        self._rbf = True
+
     oldfeeChanged = pyqtSignal()
     @pyqtProperty(QEAmount, notify=oldfeeChanged)
     def oldfee(self):
@@ -552,15 +553,15 @@ class QETxRbfFeeBumper(TxFeeSlider, TxMonMixin):
 class QETxCanceller(TxFeeSlider, TxMonMixin):
     _logger = get_logger(__name__)
 
-    _oldfee = QEAmount()
-    _oldfee_rate = 0
-    _orig_tx = None
-    _txid = ''
-    _rbf = True
-
     def __init__(self, parent=None):
         super().__init__(parent)
 
+        self._oldfee = QEAmount()
+        self._oldfee_rate = 0
+        self._orig_tx = None
+        self._txid = ''
+        self._rbf = True
+
     oldfeeChanged = pyqtSignal()
     @pyqtProperty(QEAmount, notify=oldfeeChanged)
     def oldfee(self):
@@ -658,24 +659,24 @@ class QETxCanceller(TxFeeSlider, TxMonMixin):
 class QETxCpfpFeeBumper(TxFeeSlider, TxMonMixin):
     _logger = get_logger(__name__)
 
-    _input_amount = QEAmount()
-    _output_amount = QEAmount()
-    _fee_for_child = QEAmount()
-    _total_fee = QEAmount()
-    _total_fee_rate = 0
-    _total_size = 0
-
-    _parent_tx = None
-    _new_tx = None
-    _parent_tx_size = 0
-    _parent_fee = 0
-    _max_fee = 0
-    _txid = ''
-    _rbf = True
-
     def __init__(self, parent=None):
         super().__init__(parent)
 
+        self._input_amount = QEAmount()
+        self._output_amount = QEAmount()
+        self._fee_for_child = QEAmount()
+        self._total_fee = QEAmount()
+        self._total_fee_rate = 0
+        self._total_size = 0
+
+        self._parent_tx = None
+        self._new_tx = None
+        self._parent_tx_size = 0
+        self._parent_fee = 0
+        self._max_fee = 0
+        self._txid = ''
+        self._rbf = True
+
     totalFeeChanged = pyqtSignal()
     @pyqtProperty(QEAmount, notify=totalFeeChanged)
     def totalFee(self):
diff --git a/electrum/gui/qml/qewallet.py b/electrum/gui/qml/qewallet.py
index d2fbda4bf..656169afe 100644
--- a/electrum/gui/qml/qewallet.py
+++ b/electrum/gui/qml/qewallet.py
@@ -74,28 +74,29 @@ class QEWallet(AuthMixin, QObject, QtEventListener):
 
     _network_signal = pyqtSignal(str, object)
 
-    _isUpToDate = False
-    _synchronizing = False
-    _synchronizing_progress = ''
-
-    _lightningbalance = QEAmount()
-    _confirmedbalance = QEAmount()
-    _unconfirmedbalance = QEAmount()
-    _frozenbalance = QEAmount()
-    _totalbalance = QEAmount()
-    _lightningcanreceive = QEAmount()
-    _lightningcansend = QEAmount()
-
     def __init__(self, wallet: 'Abstract_Wallet', parent=None):
         super().__init__(parent)
         self.wallet = wallet
 
+        self._isUpToDate = False
+        self._synchronizing = False
+        self._synchronizing_progress = ''
+
         self._historyModel = None
         self._addressModel = None
         self._requestModel = None
         self._invoiceModel = None
         self._channelModel = None
 
+        self._lightningbalance = QEAmount()
+        self._confirmedbalance = QEAmount()
+        self._unconfirmedbalance = QEAmount()
+        self._frozenbalance = QEAmount()
+        self._totalbalance = QEAmount()
+        self._lightningcanreceive = QEAmount()
+        self._lightningcansend = QEAmount()
+
+
         self.tx_notification_queue = queue.Queue()
         self.tx_notification_last_time = 0
 
@@ -420,6 +421,8 @@ class QEWallet(AuthMixin, QObject, QtEventListener):
     def lightningBalance(self):
         if self.isLightning:
             self._lightningbalance.satsInt = int(self.wallet.lnworker.get_balance())
+        # else:
+        #     self._lightningbalance.satsInt = 0
         return self._lightningbalance
 
     @pyqtProperty(QEAmount, notify=balanceChanged)
diff --git a/electrum/gui/qml/qewalletdb.py b/electrum/gui/qml/qewalletdb.py
index 62807c7d6..346e6c0d9 100644
--- a/electrum/gui/qml/qewalletdb.py
+++ b/electrum/gui/qml/qewalletdb.py
@@ -10,14 +10,6 @@ from electrum.util import InvalidPassword
 from electrum import keystore
 
 class QEWalletDB(QObject):
-    def __init__(self, parent=None):
-        super().__init__(parent)
-
-        from .qeapp import ElectrumQmlApplication
-        self.daemon = ElectrumQmlApplication._daemon
-
-        self.reset()
-
     _logger = get_logger(__name__)
 
     fileNotFound = pyqtSignal()
@@ -31,6 +23,14 @@ class QEWalletDB(QObject):
     readyChanged = pyqtSignal()
     invalidPassword = pyqtSignal()
 
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        from .qeapp import ElectrumQmlApplication
+        self.daemon = ElectrumQmlApplication._daemon
+
+        self.reset()
+
     def reset(self):
         self._path = None
         self._needsPassword = False