qt: add some type hints

electrum/gui/qt/__init__.py

@@ -28,7 +28,7 @@ import signal
 import sys
 import traceback
 import threading
-from typing import Optional
+from typing import Optional, TYPE_CHECKING
 
 
 try:
@@ -57,6 +57,11 @@ from .network_dialog import NetworkDialog
 from .stylesheet_patcher import patch_qt_stylesheet
 from .lightning_dialog import LightningDialog
 
+if TYPE_CHECKING:
+    from electrum.daemon import Daemon
+    from electrum.simple_config import SimpleConfig
+    from electrum.plugin import Plugins
+
 
 class OpenFileEventFilter(QObject):
     def __init__(self, windows):
@@ -82,7 +87,7 @@ class QNetworkUpdatedSignalObject(QObject):
 class ElectrumGui(Logger):
 
     @profiler
-    def __init__(self, config, daemon, plugins):
+    def __init__(self, config: 'SimpleConfig', daemon: 'Daemon', plugins: 'Plugins'):
         set_language(config.get('language', get_default_language()))
         Logger.__init__(self)
         # Uncomment this call to verify objects are being properly

electrum/gui/qt/installwizard.py

@@ -6,13 +6,13 @@ import os
 import sys
 import threading
 import traceback
-from typing import Tuple, List, Callable, NamedTuple, Optional
+from typing import Tuple, List, Callable, NamedTuple, Optional, TYPE_CHECKING
 
 from PyQt5.QtCore import QRect, QEventLoop, Qt, pyqtSignal
 from PyQt5.QtGui import QPalette, QPen, QPainter, QPixmap
 from PyQt5.QtWidgets import (QWidget, QDialog, QLabel, QHBoxLayout, QMessageBox,
                              QVBoxLayout, QLineEdit, QFileDialog, QPushButton,
-                             QGridLayout, QSlider, QScrollArea)
+                             QGridLayout, QSlider, QScrollArea, QApplication)
 
 from electrum.wallet import Wallet, Abstract_Wallet
 from electrum.storage import WalletStorage
@@ -25,7 +25,11 @@ from .network_dialog import NetworkChoiceLayout
 from .util import (MessageBoxMixin, Buttons, icon_path, ChoicesLayout, WWLabel,
                    InfoButton, char_width_in_lineedit)
 from .password_dialog import PasswordLayout, PasswordLayoutForHW, PW_NEW
-from electrum.plugin import run_hook
+from electrum.plugin import run_hook, Plugins
+
+if TYPE_CHECKING:
+    from electrum.simple_config import SimpleConfig
+
 
 MSG_ENTER_PASSWORD = _("Choose a password to encrypt your wallet keys.") + '\n'\
                      + _("Leave this field empty if you want to disable encryption.")
@@ -115,7 +119,7 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
 
     accept_signal = pyqtSignal()
 
-    def __init__(self, config, app, plugins):
+    def __init__(self, config: 'SimpleConfig', app: QApplication, plugins: 'Plugins'):
         QDialog.__init__(self, None)
         BaseWizard.__init__(self, config, plugins)
         self.setWindowTitle('Electrum  -  ' + _('Install Wizard'))

electrum/gui/qt/main_window.py

@@ -36,7 +36,7 @@ import base64
 from functools import partial
 import queue
 import asyncio
-from typing import Optional
+from typing import Optional, TYPE_CHECKING
 
 from PyQt5.QtGui import QPixmap, QKeySequence, QIcon, QCursor
 from PyQt5.QtCore import Qt, QRect, QStringListModel, QSize, pyqtSignal
@@ -93,6 +93,10 @@ from .history_list import HistoryList, HistoryModel
 from .update_checker import UpdateCheck, UpdateCheckThread
 from .channels_list import ChannelsList
 
+if TYPE_CHECKING:
+    from . import ElectrumGui
+
+
 LN_NUM_PAYMENT_ATTEMPTS = 10
 
 class StatusBarButton(QPushButton):
@@ -125,7 +129,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
     computing_privkeys_signal = pyqtSignal()
     show_privkeys_signal = pyqtSignal()
 
-    def __init__(self, gui_object, wallet: Abstract_Wallet):
+    def __init__(self, gui_object: 'ElectrumGui', wallet: Abstract_Wallet):
         QMainWindow.__init__(self)
 
         self.gui_object = gui_object