Handle Qt drag and drop IgnoreAction

Also ensure dragEnterEvent and dragMoveEvent indicate the actually
performed action (copy in our case). This influences the icon shown
to the user while dragging. On Windows this will then show the actual
copy icon even if the user has modifiers pressed.

picard/ui/coverartbox.py

@@ -132,6 +132,10 @@ class CoverArtThumbnail(ActiveLabel):
         event.accept()
 
     def dropEvent(self, event):
+        if event.proposedAction() == QtCore.Qt.DropAction.IgnoreAction:
+            event.acceptProposedAction()
+            return
+
         accepted = False
         # Chromium includes the actual data of the dragged image in the drop event. This
         # is useful for Google Images, where the url links to the page that contains the image

picard/ui/itemviews.py

@@ -695,11 +695,16 @@ class BaseTreeView(QtWidgets.QTreeWidget):
         return ["text/uri-list", "application/picard.album-list"]
 
     def dragEnterEvent(self, event):
-        if not event.source() or event.mimeData().hasUrls():
+        super().dragEnterEvent(event)
+        if event.isAccepted() and (not event.source() or event.mimeData().hasUrls()):
+            event.setDropAction(QtCore.Qt.DropAction.CopyAction)
+            event.accept()
+
+    def dragMoveEvent(self, event):
+        super().dragMoveEvent(event)
+        if event.isAccepted() and (not event.source() or event.mimeData().hasUrls()):
             event.setDropAction(QtCore.Qt.DropAction.CopyAction)
             event.accept()
-        else:
-            event.acceptProposedAction()
 
     def startDrag(self, supportedActions):
         """Start drag, *without* using pixmap."""
@@ -763,6 +768,9 @@ class BaseTreeView(QtWidgets.QTreeWidget):
             tagger.add_paths(new_paths, target=target)
 
     def dropEvent(self, event):
+        if event.proposedAction() == QtCore.Qt.DropAction.IgnoreAction:
+            event.acceptProposedAction()
+            return
         # Dropping with Alt key pressed forces all dropped files being
         # assigned to the same track.
         if event.keyboardModifiers() == QtCore.Qt.KeyboardModifier.AltModifier:

picard/ui/options/plugins.py

@@ -247,6 +247,7 @@ class PluginsOptionsPage(OptionsPage):
         plugins.mimeTypes = self.mimeTypes
         plugins.dropEvent = self.dropEvent
         plugins.dragEnterEvent = self.dragEnterEvent
+        plugins.dragMoveEvent = self.dragMoveEvent
 
         self.ui.install_plugin.clicked.connect(self.open_plugins)
         self.ui.folder_open.clicked.connect(self.open_plugin_dir)
@@ -700,9 +701,20 @@ class PluginsOptionsPage(OptionsPage):
         event.setDropAction(QtCore.Qt.DropAction.CopyAction)
         event.accept()
 
+    def dragMoveEvent(self, event):
+        event.setDropAction(QtCore.Qt.DropAction.CopyAction)
+        event.accept()
+
     def dropEvent(self, event):
+        if event.proposedAction() == QtCore.Qt.DropAction.IgnoreAction:
+            event.acceptProposedAction()
+            return
+
         for path in (os.path.normpath(u.toLocalFile()) for u in event.mimeData().urls()):
             self.manager.install_plugin(path)
 
+        event.setDropAction(QtCore.Qt.DropAction.CopyAction)
+        event.accept()
+
 
 register_options_page(PluginsOptionsPage)