Some type-hinting for various qt base objects

qt/me/details_dialog.py

@@ -15,7 +15,7 @@ tr = trget("ui")
 
 
 class DetailsDialog(DetailsDialogBase):
-    def _setupUi(self):
+    def _setupUi(self) -> None:
         self.setWindowTitle(tr("Details"))
         self.resize(502, 295)
         self.setMinimumSize(QSize(250, 250))

qt/me/preferences_dialog.py

@@ -4,27 +4,22 @@
 # which should be included with this package. The terms are also available at
 # http://www.gnu.org/licenses/gpl-3.0.html
 
+from typing import Callable
 from PyQt5.QtCore import QSize
-from PyQt5.QtWidgets import (
+from PyQt5.QtWidgets import QVBoxLayout, QHBoxLayout, QLabel, QSizePolicy, QSpacerItem, QWidget, QCheckBox
-    QVBoxLayout,
-    QHBoxLayout,
-    QLabel,
-    QSizePolicy,
-    QSpacerItem,
-    QWidget,
-)
 
 from hscommon.trans import trget
 from core.app import AppMode
 from core.scanner import ScanType
+from qt.preferences import Preferences
 
-from qt.preferences_dialog import PreferencesDialogBase
+from qt.preferences_dialog import PreferencesDialogBase, Sections
 
 tr = trget("ui")
 
 
 class PreferencesDialog(PreferencesDialogBase):
-    def _setupPreferenceWidgets(self):
+    def _setupPreferenceWidgets(self) -> None:
         self._setupFilterHardnessBox()
         self.widgetsVLayout.addLayout(self.filterHardnessHLayout)
         self.widget = QWidget(self)
@@ -70,7 +65,7 @@ class PreferencesDialog(PreferencesDialogBase):
         self.widgetsVLayout.addWidget(self.ignoreHardlinkMatches)
         self._setupBottomPart()
 
-    def _load(self, prefs, setchecked, section):
+    def _load(self, prefs: Preferences, setchecked: Callable[[QCheckBox, bool], None], section: Sections) -> None:
         setchecked(self.tagTrackBox, prefs.scan_tag_track)
         setchecked(self.tagArtistBox, prefs.scan_tag_artist)
         setchecked(self.tagAlbumBox, prefs.scan_tag_album)
@@ -99,7 +94,7 @@ class PreferencesDialog(PreferencesDialogBase):
         self.tagGenreBox.setEnabled(tag_based)
         self.tagYearBox.setEnabled(tag_based)
 
-    def _save(self, prefs, ischecked):
+    def _save(self, prefs: Preferences, ischecked: Callable[[QCheckBox], bool]) -> None:
         prefs.scan_tag_track = ischecked(self.tagTrackBox)
         prefs.scan_tag_artist = ischecked(self.tagArtistBox)
         prefs.scan_tag_album = ischecked(self.tagAlbumBox)

qt/pe/details_dialog.py

@@ -4,10 +4,12 @@
 # which should be included with this package. The terms are also available at
 # http://www.gnu.org/licenses/gpl-3.0.html
 
-from PyQt5.QtCore import Qt, QSize, pyqtSignal, pyqtSlot
+from typing import Union
-from PyQt5.QtWidgets import QAbstractItemView, QSizePolicy, QGridLayout, QSplitter, QFrame
+from PyQt5.QtCore import Qt, QSize, pyqtSignal
+from PyQt5.QtWidgets import QWidget, QAbstractItemView, QSizePolicy, QGridLayout, QSplitter, QFrame
 from PyQt5.QtGui import QResizeEvent
 from hscommon.trans import trget
+from qt import app
 from qt.details_dialog import DetailsDialog as DetailsDialogBase
 from qt.details_table import DetailsTable
 from qt.pe.image_viewer import ViewerToolBar, ScrollAreaImageViewer, ScrollAreaController
@@ -16,15 +18,15 @@ tr = trget("ui")
 
 
 class DetailsDialog(DetailsDialogBase):
-    def __init__(self, parent, app):
+    def __init__(self, parent: QWidget, app: "app.DupeGuru") -> None:
-        self.vController = None
+        self.vController: Union[ScrollAreaController, None] = None
         super().__init__(parent, app)
 
-    def _setupUi(self):
+    def _setupUi(self) -> None:
         self.setWindowTitle(tr("Details"))
         self.resize(502, 502)
         self.setMinimumSize(QSize(250, 250))
-        self.splitter = QSplitter(Qt.Vertical)
+        self.splitter = QSplitter(Qt.Orientation.Vertical)
         self.topFrame = EmittingFrame()
         self.topFrame.setFrameShape(QFrame.StyledPanel)
         self.horizontalLayout = QGridLayout()
@@ -47,8 +49,8 @@ class DetailsDialog(DetailsDialogBase):
         self.vController = ScrollAreaController(self)
 
         self.verticalToolBar = ViewerToolBar(self, self.vController)
-        self.verticalToolBar.setOrientation(Qt.Orientation(Qt.Vertical))
+        self.verticalToolBar.setOrientation(Qt.Orientation.Vertical)
-        self.horizontalLayout.addWidget(self.verticalToolBar, 1, 1, 1, 1, Qt.AlignCenter)
+        self.horizontalLayout.addWidget(self.verticalToolBar, 1, 1, 1, 1, Qt.AlignmentFlag.AlignCenter)
 
         self.referenceImageViewer = ScrollAreaImageViewer(self, "referenceImage")
         self.horizontalLayout.addWidget(self.referenceImageViewer, 0, 2, 3, 1)
@@ -73,7 +75,7 @@ class DetailsDialog(DetailsDialogBase):
 
         self.topFrame.resized.connect(self.resizeEvent)
 
-    def _update(self):
+    def _update(self) -> None:
         if self.vController is None:  # Not yet constructed!
             return
         if not self.app.model.selected_dupes:
@@ -87,15 +89,14 @@ class DetailsDialog(DetailsDialogBase):
         self.vController.updateView(ref, dupe, group)
 
     # --- Override
-    @pyqtSlot(QResizeEvent)
+    def resizeEvent(self, event: QResizeEvent) -> None:
-    def resizeEvent(self, event):
         self.ensure_same_sizes()
         if self.vController is None or not self.vController.bestFit:
             return
         # Only update the scaled down pixmaps
         self.vController.updateBothImages()
 
-    def show(self):
+    def show(self) -> None:
         # Give the splitter a maximum height to reach. This is assuming that
         # all rows below their headers have the same height
         self.tableView.setMaximumHeight(
@@ -108,7 +109,7 @@ class DetailsDialog(DetailsDialogBase):
         self.ensure_same_sizes()
         self._update()
 
-    def ensure_same_sizes(self):
+    def ensure_same_sizes(self) -> None:
         # HACK This ensures same size while shrinking.
         # ReferenceViewer might be 1 pixel shorter in width
         # due to the toolbar in the middle keeping the same width,
@@ -126,7 +127,7 @@ class DetailsDialog(DetailsDialogBase):
             self.selectedImageViewer.resize(self.referenceImageViewer.size())
 
     # model --> view
-    def refresh(self):
+    def refresh(self) -> None:
         DetailsDialogBase.refresh(self)
         if self.isVisible():
             self._update()
@@ -137,5 +138,5 @@ class EmittingFrame(QFrame):
 
     resized = pyqtSignal(QResizeEvent)
 
-    def resizeEvent(self, event):
+    def resizeEvent(self, event: QResizeEvent) -> None:
         self.resized.emit(event)

qt/pe/image_viewer.py

@@ -2,6 +2,7 @@
 # which should be included with this package. The terms are also available at
 # http://www.gnu.org/licenses/gpl-3.0.html
 
+from typing import Union, cast
 from PyQt5.QtCore import QObject, Qt, QSize, QRectF, QPointF, QPoint, pyqtSlot, pyqtSignal, QEvent
 from PyQt5.QtGui import QPixmap, QPainter, QPalette, QCursor, QIcon, QKeySequence
 from PyQt5.QtWidgets import (
@@ -17,6 +18,7 @@ from PyQt5.QtWidgets import (
     QAbstractScrollArea,
     QStyle,
 )
+from qt.details_dialog import DetailsDialog
 from hscommon.trans import trget
 from hscommon.plat import ISLINUX
 
@@ -26,7 +28,7 @@ MAX_SCALE = 12.0
 MIN_SCALE = 0.1
 
 
-def create_actions(actions, target):
+def create_actions(actions: list, target: QObject) -> None:
     # actions are list of (name, shortcut, icon, desc, func)
     for name, shortcut, icon, desc, func in actions:
         action = QAction(target)
@@ -40,9 +42,9 @@ def create_actions(actions, target):
 
 
 class ViewerToolBar(QToolBar):
-    def __init__(self, parent, controller):
+    def __init__(self, parent: DetailsDialog, controller: "BaseController") -> None:
         super().__init__(parent)
-        self.parent = parent
+        self.setParent(parent)
         self.controller = controller
         self.setupActions(controller)
         self.createButtons()
@@ -52,24 +54,21 @@ class ViewerToolBar(QToolBar):
         self.buttonNormalSize.setEnabled(False)
         self.buttonBestFit.setEnabled(False)
 
-    def setupActions(self, controller):
+    def setupActions(self, controller: "BaseController") -> None:
+        override_icons = cast(DetailsDialog, self.parent()).app.prefs.details_dialog_override_theme_icons
         # actions are list of (name, shortcut, icon, desc, func)
         ACTIONS = [
             (
                 "actionZoomIn",
                 QKeySequence.ZoomIn,
-                QIcon.fromTheme("zoom-in")
+                QIcon.fromTheme("zoom-in") if ISLINUX and not override_icons else QIcon(QPixmap(":/" + "zoom_in")),
-                if ISLINUX and not self.parent.app.prefs.details_dialog_override_theme_icons
-                else QIcon(QPixmap(":/" + "zoom_in")),
                 tr("Increase zoom"),
                 controller.zoomIn,
             ),
             (
                 "actionZoomOut",
                 QKeySequence.ZoomOut,
-                QIcon.fromTheme("zoom-out")
+                QIcon.fromTheme("zoom-out") if ISLINUX and not override_icons else QIcon(QPixmap(":/" + "zoom_out")),
-                if ISLINUX and not self.parent.app.prefs.details_dialog_override_theme_icons
-                else QIcon(QPixmap(":/" + "zoom_out")),
                 tr("Decrease zoom"),
                 controller.zoomOut,
             ),
@@ -77,7 +76,7 @@ class ViewerToolBar(QToolBar):
                 "actionNormalSize",
                 tr("Ctrl+/"),
                 QIcon.fromTheme("zoom-original")
-                if ISLINUX and not self.parent.app.prefs.details_dialog_override_theme_icons
+                if ISLINUX and not override_icons
                 else QIcon(QPixmap(":/" + "zoom_original")),
                 tr("Normal size"),
                 controller.zoomNormalSize,
@@ -86,7 +85,7 @@ class ViewerToolBar(QToolBar):
                 "actionBestFit",
                 tr("Ctrl+*"),
                 QIcon.fromTheme("zoom-best-fit")
-                if ISLINUX and not self.parent.app.prefs.details_dialog_override_theme_icons
+                if ISLINUX and not override_icons
                 else QIcon(QPixmap(":/" + "zoom_best_fit")),
                 tr("Best fit"),
                 controller.zoomBestFit,
@@ -96,12 +95,12 @@ class ViewerToolBar(QToolBar):
         # the popup menu work in the toolbar (if resized below minimum height)
         create_actions(ACTIONS, self)
 
-    def createButtons(self):
+    def createButtons(self) -> None:
         self.buttonImgSwap = QToolButton(self)
-        self.buttonImgSwap.setToolButtonStyle(Qt.ToolButtonIconOnly)
+        self.buttonImgSwap.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)
         self.buttonImgSwap.setIcon(
-            QIcon.fromTheme("view-refresh", self.style().standardIcon(QStyle.SP_BrowserReload))
+            QIcon.fromTheme("view-refresh", self.style().standardIcon(QStyle.StandardPixmap.SP_BrowserReload))
-            if ISLINUX and not self.parent.app.prefs.details_dialog_override_theme_icons
+            if ISLINUX and not cast(DetailsDialog, self.parent()).app.prefs.details_dialog_override_theme_icons
             else QIcon(QPixmap(":/" + "exchange"))
         )
         self.buttonImgSwap.setText("Swap images")
@@ -110,22 +109,22 @@ class ViewerToolBar(QToolBar):
         self.buttonImgSwap.released.connect(self.controller.swapImages)
 
         self.buttonZoomIn = QToolButton(self)
-        self.buttonZoomIn.setToolButtonStyle(Qt.ToolButtonIconOnly)
+        self.buttonZoomIn.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)
         self.buttonZoomIn.setDefaultAction(self.actionZoomIn)
         self.buttonZoomIn.setEnabled(False)
 
         self.buttonZoomOut = QToolButton(self)
-        self.buttonZoomOut.setToolButtonStyle(Qt.ToolButtonIconOnly)
+        self.buttonZoomOut.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)
         self.buttonZoomOut.setDefaultAction(self.actionZoomOut)
         self.buttonZoomOut.setEnabled(False)
 
         self.buttonNormalSize = QToolButton(self)
-        self.buttonNormalSize.setToolButtonStyle(Qt.ToolButtonIconOnly)
+        self.buttonNormalSize.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)
         self.buttonNormalSize.setDefaultAction(self.actionNormalSize)
         self.buttonNormalSize.setEnabled(True)
 
         self.buttonBestFit = QToolButton(self)
-        self.buttonBestFit.setToolButtonStyle(Qt.ToolButtonIconOnly)
+        self.buttonBestFit.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)
         self.buttonBestFit.setDefaultAction(self.actionBestFit)
         self.buttonBestFit.setEnabled(False)
 
@@ -141,10 +140,10 @@ class BaseController(QObject):
     Base proxy interface to keep image viewers synchronized.
     Relays function calls, keep tracks of things."""
 
-    def __init__(self, parent):
+    def __init__(self, parent: QObject) -> None:
         super().__init__()
-        self.selectedViewer = None
+        self.selectedViewer: Union[ScrollAreaImageViewer, None] = None
-        self.referenceViewer = None
+        self.referenceViewer: Union[ScrollAreaImageViewer, None] = None
         # cached pixmaps
         self.selectedPixmap = QPixmap()
         self.referencePixmap = QPixmap()
@@ -152,22 +151,24 @@ class BaseController(QObject):
         self.scaledReferencePixmap = QPixmap()
         self.current_scale = 1.0
         self.bestFit = True
-        self.parent = parent  # To change buttons' states
+        self.setParent(parent)  # To change buttons' states
         self.cached_group = None
         self.same_dimensions = True
 
-    def setupViewers(self, selected_viewer, reference_viewer):
+    def setupViewers(self, selected_viewer: "ScrollAreaImageViewer", reference_viewer: "ScrollAreaImageViewer") -> None:
         self.selectedViewer = selected_viewer
         self.referenceViewer = reference_viewer
         self.selectedViewer.controller = self
         self.referenceViewer.controller = self
         self._setupConnections()
 
-    def _setupConnections(self):
+    def _setupConnections(self) -> None:
-        self.selectedViewer.connectMouseSignals()
+        if self.selectedViewer is not None:
-        self.referenceViewer.connectMouseSignals()
+            self.selectedViewer.connectMouseSignals()
+        if self.referenceViewer is not None:
+            self.referenceViewer.connectMouseSignals()
 
-    def updateView(self, ref, dupe, group):
+    def updateView(self, ref, dupe, group) -> None:
         # To keep current scale accross dupes from the same group
         previous_same_dimensions = self.same_dimensions
         self.same_dimensions = True
@@ -206,13 +207,15 @@ class BaseController(QObject):
         if ignore_update:
             self.selectedViewer.ignore_signal = False
 
-    def _updateImage(self, pixmap, viewer, same_group=False):
+    def _updateImage(
+        self, pixmap: QPixmap, viewer: "ScrollAreaImageViewer", same_group: bool = False
+    ) -> Union[QSize, None]:
         # WARNING this is called on every resize event, might need to split
         # into a separate function depending on the implementation used
         if pixmap.isNull():
             # This should disable the blank widget
             viewer.setImage(pixmap)
-            return
+            return None
         target_size = viewer.size()
         if not viewer.bestFit:
             if same_group:
@@ -220,14 +223,18 @@ class BaseController(QObject):
                 return target_size
             # zoomed in state, expand
             # only if not same_group, we need full update
-            scaledpixmap = pixmap.scaled(target_size, Qt.KeepAspectRatioByExpanding, Qt.FastTransformation)
+            scaledpixmap = pixmap.scaled(
+                target_size, Qt.AspectRatioMode.KeepAspectRatioByExpanding, Qt.TransformationMode.FastTransformation
+            )
         else:
             # best fit, keep ratio always
-            scaledpixmap = pixmap.scaled(target_size, Qt.KeepAspectRatio, Qt.FastTransformation)
+            scaledpixmap = pixmap.scaled(
+                target_size, Qt.AspectRatioMode.KeepAspectRatio, Qt.TransformationMode.FastTransformation
+            )
         viewer.setImage(scaledpixmap)
         return target_size
 
-    def resetState(self):
+    def resetState(self) -> None:
         """Only called when the group of dupes has changed. We reset our
         controller internal state and buttons, center view on viewers."""
         self.selectedPixmap = QPixmap()
@@ -248,7 +255,7 @@ class BaseController(QObject):
         self.parent.verticalToolBar.buttonNormalSize.setEnabled(True)
         self.parent.verticalToolBar.buttonBestFit.setEnabled(False)  # active mode by default
 
-    def resetViewersState(self):
+    def resetViewersState(self) -> None:
         """No item from the model, disable and clear everything."""
         # only called by the details dialog
         self.selectedPixmap = QPixmap()
@@ -277,36 +284,40 @@ class BaseController(QObject):
         self.referenceViewer.setEnabled(False)
 
     @pyqtSlot()
-    def zoomIn(self):
+    def zoomIn(self) -> None:
         self.scaleImagesBy(1.25)
 
     @pyqtSlot()
-    def zoomOut(self):
+    def zoomOut(self) -> None:
         self.scaleImagesBy(0.8)
 
     @pyqtSlot(float)
-    def scaleImagesBy(self, factor):
+    def scaleImagesBy(self, factor: float) -> None:
         """Compute new scale from factor and scale."""
         self.current_scale *= factor
-        self.selectedViewer.scaleBy(factor)
+        if self.selectedViewer is not None:
-        self.referenceViewer.scaleBy(factor)
+            self.selectedViewer.scaleBy(factor)
+        if self.referenceViewer is not None:
+            self.referenceViewer.scaleBy(factor)
         self.updateButtons()
 
     @pyqtSlot(float)
-    def scaleImagesAt(self, scale):
+    def scaleImagesAt(self, scale: float) -> None:
         """Scale at a pre-computed scale."""
         self.current_scale = scale
-        self.selectedViewer.scaleAt(scale)
+        if self.selectedViewer is not None:
-        self.referenceViewer.scaleAt(scale)
+            self.selectedViewer.scaleAt(scale)
+        if self.referenceViewer is not None:
+            self.referenceViewer.scaleAt(scale)
         self.updateButtons()
 
-    def updateButtons(self):
+    def updateButtons(self) -> None:
         self.parent.verticalToolBar.buttonZoomIn.setEnabled(self.current_scale < MAX_SCALE)
         self.parent.verticalToolBar.buttonZoomOut.setEnabled(self.current_scale > MIN_SCALE)
         self.parent.verticalToolBar.buttonNormalSize.setEnabled(round(self.current_scale, 1) != 1.0)
         self.parent.verticalToolBar.buttonBestFit.setEnabled(self.bestFit is False)
 
-    def updateButtonsAsPerDimensions(self, previous_same_dimensions):
+    def updateButtonsAsPerDimensions(self, previous_same_dimensions: bool) -> None:
         if not self.same_dimensions:
             self.parent.verticalToolBar.buttonZoomIn.setEnabled(False)
             self.parent.verticalToolBar.buttonZoomOut.setEnabled(False)
@@ -323,7 +334,7 @@ class BaseController(QObject):
                 self.parent.verticalToolBar.buttonImgSwap.setEnabled(False)
 
     @pyqtSlot()
-    def zoomBestFit(self):
+    def zoomBestFit(self) -> None:
         """Setup before scaling to bestfit"""
         self.setBestFit(True)
         self.current_scale = 1.0
@@ -352,7 +363,7 @@ class BaseController(QObject):
         self.referenceViewer.bestFit = value
 
     @pyqtSlot()
-    def zoomNormalSize(self):
+    def zoomNormalSize(self) -> None:
         self.setBestFit(False)
         self.current_scale = 1.0
 
@@ -373,14 +384,14 @@ class BaseController(QObject):
         self.parent.verticalToolBar.buttonNormalSize.setEnabled(False)
         self.parent.verticalToolBar.buttonBestFit.setEnabled(True)
 
-    def centerViews(self, only_selected=False):
+    def centerViews(self, only_selected: bool = False) -> None:
         self.selectedViewer.centerViewAndUpdate()
         if only_selected:
             return
         self.referenceViewer.centerViewAndUpdate()
 
     @pyqtSlot()
-    def swapImages(self):
+    def swapImages(self) -> None:
         # swap the columns in the details table as well
         self.parent.tableView.horizontalHeader().swapSections(0, 1)
 
@@ -388,17 +399,17 @@ class BaseController(QObject):
 class QWidgetController(BaseController):
     """Specialized version for QWidget-based viewers."""
 
-    def __init__(self, parent):
+    def __init__(self, parent: QObject) -> None:
         super().__init__(parent)
 
-    def _updateImage(self, *args):
+    def _updateImage(self, *args) -> Union[QSize, None]:
         ret = super()._updateImage(*args)
         # Fix alignment when resizing window
         self.centerViews()
         return ret
 
     @pyqtSlot(QPointF)
-    def onDraggedMouse(self, delta):
+    def onDraggedMouse(self, delta) -> None:
         if not self.same_dimensions:
             return
         if self.sender() is self.referenceViewer:
@@ -407,7 +418,7 @@ class QWidgetController(BaseController):
             self.referenceViewer.onDraggedMouse(delta)
 
     @pyqtSlot()
-    def swapImages(self):
+    def swapImages(self) -> None:
         self.selectedViewer._pixmap.swap(self.referenceViewer._pixmap)
         self.selectedViewer.centerViewAndUpdate()
         self.referenceViewer.centerViewAndUpdate()
@@ -417,15 +428,15 @@ class QWidgetController(BaseController):
 class ScrollAreaController(BaseController):
     """Specialized version fro QLabel-based viewers."""
 
-    def __init__(self, parent):
+    def __init__(self, parent: QObject) -> None:
         super().__init__(parent)
 
-    def _setupConnections(self):
+    def _setupConnections(self) -> None:
         super()._setupConnections()
         self.selectedViewer.connectScrollBars()
         self.referenceViewer.connectScrollBars()
 
-    def updateBothImages(self, same_group=False):
+    def updateBothImages(self, same_group: bool = False) -> None:
         super().updateBothImages(same_group)
         if not self.referenceViewer.isEnabled():
             return
@@ -433,7 +444,7 @@ class ScrollAreaController(BaseController):
         self.referenceViewer._verticalScrollBar.setValue(self.selectedViewer._verticalScrollBar.value())
 
     @pyqtSlot(QPoint)
-    def onDraggedMouse(self, delta):
+    def onDraggedMouse(self, delta) -> None:
         self.selectedViewer.ignore_signal = True
         self.referenceViewer.ignore_signal = True
 
@@ -450,21 +461,21 @@ class ScrollAreaController(BaseController):
         self.referenceViewer.ignore_signal = False
 
     @pyqtSlot()
-    def swapImages(self):
+    def swapImages(self) -> None:
         self.referenceViewer._pixmap.swap(self.selectedViewer._pixmap)
         self.referenceViewer.setCachedPixmap()
         self.selectedViewer.setCachedPixmap()
         super().swapImages()
 
     @pyqtSlot(float, QPointF)
-    def onMouseWheel(self, scale, delta):
+    def onMouseWheel(self, scale: float, delta: QPointF) -> None:
         self.scaleImagesAt(scale)
         self.selectedViewer.adjustScrollBarsScaled(delta)
         # Signal from scrollbars will automatically change the other:
         # self.referenceViewer.adjustScrollBarsScaled(delta)
 
     @pyqtSlot(int)
-    def onVScrollBarChanged(self, value):
+    def onVScrollBarChanged(self, value: int) -> None:
         if not self.same_dimensions:
             return
         if self.sender() is self.referenceViewer._verticalScrollBar:
@@ -475,7 +486,7 @@ class ScrollAreaController(BaseController):
                 self.referenceViewer._verticalScrollBar.setValue(value)
 
     @pyqtSlot(int)
-    def onHScrollBarChanged(self, value):
+    def onHScrollBarChanged(self, value: int) -> None:
         if not self.same_dimensions:
             return
         if self.sender() is self.referenceViewer._horizontalScrollBar:
@@ -486,13 +497,13 @@ class ScrollAreaController(BaseController):
                 self.referenceViewer._horizontalScrollBar.setValue(value)
 
     @pyqtSlot(float)
-    def scaleImagesBy(self, factor):
+    def scaleImagesBy(self, factor: float) -> None:
         super().scaleImagesBy(factor)
         # The other is automatically updated via sigals
         self.selectedViewer.adjustScrollBarsFactor(factor)
 
     @pyqtSlot()
-    def zoomBestFit(self):
+    def zoomBestFit(self) -> None:
         # Disable scrollbars to avoid GridLayout size rounding glitch
         super().zoomBestFit()
         if self.referencePixmap.isNull():

qt/preferences_dialog.py

@@ -4,6 +4,7 @@
 # which should be included with this package. The terms are also available at
 # http://www.gnu.org/licenses/gpl-3.0.html
 
+from typing import Callable, Union, cast
 from PyQt5.QtCore import Qt, QSize, pyqtSlot
 from PyQt5.QtWidgets import (
     QDialog,
@@ -28,11 +29,12 @@ from PyQt5.QtWidgets import (
     QGroupBox,
     QFormLayout,
 )
-from PyQt5.QtGui import QPixmap, QIcon
+from PyQt5.QtGui import QPixmap, QIcon, QShowEvent
 from hscommon import desktop, plat
 
 from hscommon.trans import trget
 from hscommon.plat import ISLINUX
+from qt import app
 from qt.util import horizontal_wrap, move_to_screen_center
 from qt.preferences import get_langnames
 from enum import Flag, auto
@@ -52,8 +54,10 @@ class Sections(Flag):
 
 
 class PreferencesDialogBase(QDialog):
-    def __init__(self, parent, app, **kwargs):
+    def __init__(self, parent: QWidget, app: "app.DupeGuru", **kwargs) -> None:
-        flags = Qt.CustomizeWindowHint | Qt.WindowTitleHint | Qt.WindowSystemMenuHint
+        flags = Qt.WindowType(
+            Qt.WindowType.CustomizeWindowHint | Qt.WindowType.WindowTitleHint | Qt.WindowType.WindowSystemMenuHint
+        )
         super().__init__(parent, flags, **kwargs)
         self.app = app
         self.supportedLanguages = dict(sorted(get_langnames().items(), key=lambda item: item[1]))
@@ -65,7 +69,7 @@ class PreferencesDialogBase(QDialog):
         self.buttonBox.accepted.connect(self.accept)
         self.buttonBox.rejected.connect(self.reject)
 
-    def _setupFilterHardnessBox(self):
+    def _setupFilterHardnessBox(self) -> None:
         self.filterHardnessHLayout = QHBoxLayout()
         self.filterHardnessLabel = QLabel(self)
         self.filterHardnessLabel.setText(tr("Filter Hardness:"))
@@ -84,7 +88,7 @@ class PreferencesDialogBase(QDialog):
         self.filterHardnessSlider.setMinimum(1)
         self.filterHardnessSlider.setMaximum(100)
         self.filterHardnessSlider.setTracking(True)
-        self.filterHardnessSlider.setOrientation(Qt.Horizontal)
+        self.filterHardnessSlider.setOrientation(Qt.Orientation.Horizontal)
         self.filterHardnessHLayoutSub1.addWidget(self.filterHardnessSlider)
         self.filterHardnessLabel = QLabel(self)
         self.filterHardnessLabel.setText("100")
@@ -104,7 +108,7 @@ class PreferencesDialogBase(QDialog):
         self.filterHardnessVLayout.addLayout(self.filterHardnessHLayoutSub2)
         self.filterHardnessHLayout.addLayout(self.filterHardnessVLayout)
 
-    def _setupBottomPart(self):
+    def _setupBottomPart(self) -> None:
         # The bottom part of the pref panel is always the same in all editions.
         self.copyMoveLabel = QLabel(self)
         self.copyMoveLabel.setText(tr("Copy and Move:"))
@@ -120,7 +124,7 @@ class PreferencesDialogBase(QDialog):
         self.customCommandEdit = QLineEdit(self)
         self.widgetsVLayout.addWidget(self.customCommandEdit)
 
-    def _setupDisplayPage(self):
+    def _setupDisplayPage(self) -> None:
         self.ui_groupbox = QGroupBox("&" + tr("General Interface"))
         layout = QVBoxLayout()
         self.languageLabel = QLabel(tr("Language:"), self)
@@ -171,7 +175,7 @@ On MacOS, the tab bar will fill up the window's width instead."
         formlayout.addRow(tr("Reference background color:"), self.result_table_ref_background_color)
         self.result_table_delta_foreground_color = ColorPickerButton(self)
         formlayout.addRow(tr("Delta foreground color:"), self.result_table_delta_foreground_color)
-        formlayout.setLabelAlignment(Qt.AlignLeft)
+        formlayout.setLabelAlignment(Qt.AlignmentFlag.AlignLeft)
 
         # Keep same vertical spacing as parent layout for consistency
         formlayout.setVerticalSpacing(self.displayVLayout.spacing())
@@ -213,7 +217,7 @@ use the modifier key to drag the floating window around"
         details_groupbox.setLayout(self.details_groupbox_layout)
         self.displayVLayout.addWidget(details_groupbox)
 
-    def _setupDebugPage(self):
+    def _setupDebugPage(self) -> None:
         self._setupAddCheckbox("debugModeBox", tr("Debug mode (restart required)"))
         self._setupAddCheckbox("profile_scan_box", tr("Profile scan operation"))
         self.profile_scan_box.setToolTip(tr("Profile the scan operation and save logs for optimization."))
@@ -221,22 +225,22 @@ use the modifier key to drag the floating window around"
         self.debugVLayout.addWidget(self.profile_scan_box)
         self.debug_location_label = QLabel(
             tr('Logs located in: <a href="{}">{}</a>').format(self.app.model.appdata, self.app.model.appdata),
-            wordWrap=True,
         )
+        self.debug_location_label.setWordWrap(True)
         self.debugVLayout.addWidget(self.debug_location_label)
 
-    def _setupAddCheckbox(self, name, label, parent=None):
+    def _setupAddCheckbox(self, name: str, label: str, parent: Union[QWidget, None] = None) -> None:
         if parent is None:
             parent = self
         cb = QCheckBox(parent)
         cb.setText(label)
         setattr(self, name, cb)
 
-    def _setupPreferenceWidgets(self):
+    def _setupPreferenceWidgets(self) -> None:
         # Edition-specific
         pass
 
-    def _setupUi(self):
+    def _setupUi(self) -> None:
         self.setWindowTitle(tr("Options"))
         self.setSizeGripEnabled(False)
         self.setModal(True)
@@ -262,7 +266,7 @@ use the modifier key to drag the floating window around"
         )
         self.mainVLayout.addWidget(self.tabwidget)
         self.mainVLayout.addWidget(self.buttonBox)
-        self.layout().setSizeConstraint(QLayout.SetFixedSize)
+        self.layout().setSizeConstraint(QLayout.SizeConstraint.SetFixedSize)
         self.tabwidget.addTab(self.page_general, tr("General"))
         self.tabwidget.addTab(self.page_display, tr("Display"))
         self.tabwidget.addTab(self.page_debug, tr("Debug"))
@@ -270,20 +274,20 @@ use the modifier key to drag the floating window around"
         self.widgetsVLayout.addStretch(0)
         self.debugVLayout.addStretch(0)
 
-    def _load(self, prefs, setchecked, section):
+    def _load(self, prefs: Preferences, setchecked: Callable[[QCheckBox, bool], None], section: Sections) -> None:
         # Edition-specific
         pass
 
-    def _save(self, prefs, ischecked):
+    def _save(self, prefs: Preferences, ischecked: Callable[[QCheckBox], bool]) -> None:
         # Edition-specific
         pass
 
-    def load(self, prefs=None, section=Sections.ALL):
+    def load(self, prefs: Union[Preferences, None] = None, section: Sections = Sections.ALL) -> None:
         if prefs is None:
             prefs = self.app.prefs
 
-        def setchecked(cb, b):
+        def setchecked(cb: QCheckBox, b: bool) -> None:
-            cb.setCheckState(Qt.Checked if b else Qt.Unchecked)
+            cb.setCheckState(Qt.CheckState.Checked if b else Qt.CheckState.Unchecked)
 
         if section & Sections.GENERAL:
             self.filterHardnessSlider.setValue(prefs.filter_hardness)
@@ -323,12 +327,12 @@ use the modifier key to drag the floating window around"
             setchecked(self.profile_scan_box, prefs.profile_scan)
         self._load(prefs, setchecked, section)
 
-    def save(self):
+    def save(self) -> None:
         prefs = self.app.prefs
         prefs.filter_hardness = self.filterHardnessSlider.value()
 
-        def ischecked(cb):
+        def ischecked(cb: QCheckBox) -> bool:
-            return cb.checkState() == Qt.Checked
+            return cb.checkState() == Qt.CheckState.Checked
 
         prefs.mix_file_kind = ischecked(self.mixFileKindBox)
         prefs.use_regexp = ischecked(self.useRegexpBox)
@@ -363,11 +367,11 @@ use the modifier key to drag the floating window around"
         self.app.prefs.language = lang_code
         self._save(prefs, ischecked)
 
-    def resetToDefaults(self, section_to_update):
+    def resetToDefaults(self, section_to_update: Sections) -> None:
         self.load(Preferences(), section_to_update)
 
     # --- Events
-    def buttonClicked(self, button):
+    def buttonClicked(self, button: QDialogButtonBox) -> None:
         role = self.buttonBox.buttonRole(button)
         if role == QDialogButtonBox.ResetRole:
             current_tab = self.tabwidget.currentWidget()
@@ -380,30 +384,32 @@ use the modifier key to drag the floating window around"
                 section_to_update = Sections.DEBUG
             self.resetToDefaults(section_to_update)
 
-    def showEvent(self, event):
+    def showEvent(self, event: QShowEvent) -> None:
         # have to do this here as the frameGeometry is not correct until shown
         move_to_screen_center(self)
         super().showEvent(event)
 
 
 class ColorPickerButton(QPushButton):
-    def __init__(self, parent):
+    def __init__(self, parent: QWidget) -> None:
         super().__init__(parent)
-        self.parent = parent
+        self.setParent(parent)
         self.color = None
         self.clicked.connect(self.onClicked)
 
     @pyqtSlot()
-    def onClicked(self):
+    def onClicked(self) -> None:
-        color = QColorDialog.getColor(self.color if self.color is not None else Qt.white, self.parent)
+        color = QColorDialog.getColor(
+            self.color if self.color is not None else Qt.GlobalColor.white, cast(QWidget, self.parent())
+        )
         self.setColor(color)
 
-    def setColor(self, color):
+    def setColor(self, color) -> None:
         size = QSize(16, 16)
         px = QPixmap(size)
         if color is None:
-            size.width = 0
+            size.setWidth(0)
-            size.height = 0
+            size.setHeight(0)
         elif not color.isValid():
             return
         else: