Eliminate main_window's self.selected_files list

- Selection is now managed completely in the Files model (outer class),
  directly from the persistent QItemSelectionModel.
- Helper functions in both files_model and main_window ease transition
- updateSelection() is also gone, as there's no selection cache.
  Selection data always comes live from the selection model.
- Also greatly simplify drag-and-drop code, using proxy & selection
  models

Author: ferdnyc

src/windows/main_window.py

@@ -399,9 +399,13 @@ def actionTitle_trigger(self, event):
 
     def actionEditTitle_trigger(self, event):
 
-        # Get selected svg title file
-        selected_file_id = self.selected_files[0]
-        file = File.get(id=selected_file_id)
+        # Get requested view item
+        index = self.filesView.indexAt(event.pos())
+
+        # look up svg title file ID from column 5 of that row
+        selected_id = index.model().sibling(index.row(), 5, index.parent()).data()
+
+        file = File.get(id=selected_id)
         file_path = file.data.get("path")
 
         # show dialog for editing title
@@ -431,9 +435,7 @@ def actionDuplicateTitle_trigger(self, event):
         file_path = None
 
         # Loop through selected files (set 1 selected file if more than 1)
-        for file_id in self.selected_files:
-            # Find matching file
-            f = File.get(id=file_id)
+        for f in self.selected_files():
             if f.data.get("path").endswith(".svg"):
                 file_path = f.data.get("path")
                 break
@@ -730,11 +732,11 @@ def actionImportFiles_trigger(self, event):
 
     def actionAdd_to_Timeline_trigger(self, event):
         # Loop through selected files
-        f = None
-        files = []
-        for file_id in self.selected_files:
-            # Find matching file
-            files.append(File.get(id=file_id))
+        files = self.selected_files()
+
+        # Bail if nothing's selected
+        if not files:
+            return
 
         # Get current position of playhead
         fps = get_app().project.get("fps")
@@ -918,14 +920,11 @@ def actionPreview_File_trigger(self, event):
         log.info('actionPreview_File_trigger')
 
         # Loop through selected files (set 1 selected file if more than 1)
-        f = None
-        for file_id in self.selected_files:
-            # Find matching file
-            f = File.get(id=file_id)
+        f = self.files_model.current_file()
 
         # Bail out if no file selected
         if not f:
-            log.info("Preview action failed, selected files: {}".format(self.selected_files))
+            log.info("Couldn't find current file for preview window")
             return
 
         # show dialog
@@ -1660,14 +1659,11 @@ def actionSplitClip_trigger(self, event):
         log.info("actionSplitClip_trigger")
 
         # Loop through selected files (set 1 selected file if more than 1)
-        f = None
-        for file_id in self.selected_files:
-            # Find matching file
-            f = File.get(id=file_id)
+        f = self.files_model.current_file()
 
         # Bail out if no file selected
         if not f:
-            log.warn("Split clip action failed, selected files: {}".format(self.selected_files))
+            log.warn("Split clip action failed, couldn't find current file")
             return
 
         # show dialog
@@ -1684,21 +1680,19 @@ def actionRemove_from_Project_trigger(self, event):
         log.info("actionRemove_from_Project_trigger")
 
         # Loop through selected files
-        for file_id in self.selected_files:
-            # Find matching file
-            f = File.get(id=file_id)
-            if f:
-                # Remove file
-                f.delete()
+        for f in self.selected_files():
+            if not f:
+                continue
 
-                # Find matching clips (if any)
-                clips = Clip.filter(file_id=file_id)
-                for c in clips:
-                    # Remove clip
-                    c.delete()
+            id = f.data["id"]
+            # Remove file
+            f.delete()
 
-        # Clear selected files
-        self.selected_files = []
+            # Find matching clips (if any)
+            clips = Clip.filter(file_id=id)
+            for c in clips:
+                # Remove clip
+                c.delete()
 
         # Refresh preview
         get_app().window.refreshFrameSignal.emit()
@@ -1891,11 +1885,11 @@ def actionFullscreen_trigger(self, event):
     def actionFile_Properties_trigger(self, event):
         log.info("Show file properties")
 
-        # Loop through selected files (set 1 selected file if more than 1)
-        f = None
-        for file_id in self.selected_files:
-            # Find matching file
-            f = File.get(id=file_id)
+        # Get current selected file (corresponding to menu, if possible)
+        f = self.files_model.current_file()
+        if not f:
+            log.warning("Couldn't find current file for properties window")
+            return
 
         # show dialog
         from windows.file_properties import FileProperties
@@ -1905,7 +1899,7 @@ def actionFile_Properties_trigger(self, event):
         if result == QDialog.Accepted:
 
             # BRUTE FORCE approach: go through all clips and update file path
-            clips = Clip.filter(file_id=file_id)
+            clips = Clip.filter(file_id=f.data["id"])
             for c in clips:
                 # update clip
                 c.data["reader"]["path"] = f.data["path"]
@@ -2191,6 +2185,22 @@ def removeSelection(self, item_id, item_type):
         # Change selected item in properties view
         self.show_property_timer.start()
 
+    def selected_files(self):
+        """ Return a list of File objects for the Project Files dock's selection """
+        return self.files_model.selected_files()
+
+    def selected_file_ids(self):
+        """ Return a list of File IDs for the Project Files dock's selection """
+        return self.files_model.selected_file_ids()
+
+    def current_file(self):
+        """ Return the Project Files dock's currently-active item as a File object """
+        return self.files_model.current_file()
+
+    def current_file_id(self):
+        """ Return the ID of the Project Files dock's currently-active item """
+        return self.files_model.current_file_id()
+
     # Update window settings in setting store
     def save_settings(self):
         s = settings.get_settings()
@@ -2399,7 +2409,6 @@ def setup_toolbars(self):
 
     def clearSelections(self):
         """Clear all selection containers"""
-        self.selected_files = []
         self.selected_clips = []
         self.selected_transitions = []
         self.selected_markers = []

src/windows/models/files_model.py

@@ -60,14 +60,14 @@ def filterAcceptsRow(self, sourceRow, sourceParent):
                 or get_app().window.filesFilter.text():
             # Fetch the file name
             index = self.sourceModel().index(sourceRow, 0, sourceParent)
-            file_name = self.sourceModel().data(index) # file name (i.e. MyVideo.mp4)
+            file_name = self.sourceModel().data(index)  # file name (i.e. MyVideo.mp4)
 
             # Fetch the media_type
             index = self.sourceModel().index(sourceRow, 3, sourceParent)
-            media_type = self.sourceModel().data(index) # media type (i.e. video, image, audio)
+            media_type = self.sourceModel().data(index)  # media type (i.e. video, image, audio)
 
             index = self.sourceModel().index(sourceRow, 2, sourceParent)
-            tags = self.sourceModel().data(index) # tags (i.e. intro, custom, etc...)
+            tags = self.sourceModel().data(index)  # tags (i.e. intro, custom, etc...)
 
             if get_app().window.actionFilesShowVideo.isChecked():
                 if not media_type == "video":
@@ -134,8 +134,7 @@ def update_model(self, clear=True, delete_file_id=None):
 
         self.ignore_updates = True
 
-        # Get window to check filters
-        win = app.window
+        # Translations
         _ = app._tr
 
         # Delete a file (if delete_file_id passed in)
@@ -299,6 +298,36 @@ def update_file_thumbnail(self, file_id):
 
         self.ignore_updates = False
 
+    def selected_file_ids(self):
+        """ Get a list of file IDs for all selected files """
+        # Get the indexes for column 5 of all selected rows
+        selected = self.selection_model.selectedRows(5)
+
+        return [idx.data() for idx in selected]
+
+    def selected_files(self):
+        """ Get a list of File objects representing the current selection """
+        files = []
+        for id in self.selected_file_ids():
+            files.append(File.get(id=id))
+        return files
+
+    def current_file_id(self):
+        """ Get the file ID of the current files-view item, or the first selection """
+        cur = self.selection_model.currentIndex()
+
+        if not cur or not cur.isValid() and self.selection_model.hasSelection():
+            cur = self.selection_model.selectedIndexes()[0]
+
+        if cur and cur.isValid():
+            return cur.sibling(cur.row(), 5).data()
+
+    def current_file(self):
+        """ Get the File object for the current files-view item, or the first selection """
+        cur_id = self.current_file_id()
+        if cur_id:
+            return File.get(id=cur_id)
+
     def __init__(self, *args):
 
         # Add self as listener to project data updates

src/windows/views/files_listview.py

@@ -47,38 +47,33 @@ class FilesListView(QListView):
     """ A ListView QWidget used on the main window """
     drag_item_size = 48
 
-    def updateSelection(self):
-        # Track selected items
-        self.selected = self.selectionModel().selectedIndexes()
-
-        # Track selected file ids on main window
-        rows = []
-        self.win.selected_files = []
-        for selection in self.selected:
-            selected_row = self.files_model.model.itemFromIndex(self.files_model.proxy_model.mapToSource(selection)).row()
-            if selected_row not in rows:
-                self.win.selected_files.append(self.files_model.model.item(selected_row, 5).text())
-                rows.append(selected_row)
-
     def contextMenuEvent(self, event):
-        # Update selection
-        self.updateSelection()
 
         # Set context menu mode
         app = get_app()
         app.context_menu_object = "files"
 
+        index = self.indexAt(event.pos())
+
+        # Build menu
         menu = QMenu(self)
 
         menu.addAction(self.win.actionImportFiles)
         menu.addAction(self.win.actionDetailsView)
-        if self.selected:
-            # If file selected, show file related options
+
+        if index.isValid():
+            # Look up the model item and our unique ID
+            model = self.model()
+
+            # Look up file_id from 5th column of row
+            id_index = index.sibling(index.row(), 5)
+            file_id = model.data(id_index, Qt.DisplayRole)
+
+            # If a valid file selected, show file related options
             menu.addSeparator()
 
             # Add edit title option (if svg file)
-            selected_file_id = self.win.selected_files[0]
-            file = File.get(id=selected_file_id)
+            file = File.get(id=file_id)
             if file and file.data.get("path").endswith(".svg"):
                 menu.addAction(self.win.actionEditTitle)
                 menu.addAction(self.win.actionDuplicateTitle)
@@ -101,16 +96,19 @@ def dragEnterEvent(self, event):
             event.setDropAction(Qt.CopyAction)
             event.accept()
 
-    def startDrag(self, event):
+    def startDrag(self, supportedActions):
         """ Override startDrag method to display custom icon """
 
+        # The relevant model for index values
+        model = self.model()
+
         # Get image of selected item
-        selected_row = self.files_model.model.itemFromIndex(self.files_model.proxy_model.mapToSource(self.selectionModel().selectedIndexes()[0])).row()
-        icon = self.files_model.model.item(selected_row, 0).icon()
+        selected_rows = self.selectionModel().selectedRows(0)
+        icon = selected_rows[0].data(Qt.DecorationRole)
 
         # Start drag operation
         drag = QDrag(self)
-        drag.setMimeData(self.files_model.proxy_model.mimeData(self.selectionModel().selectedIndexes()))
+        drag.setMimeData(model.mimeData(self.selectionModel().selectedIndexes()))
         drag.setPixmap(icon.pixmap(QSize(self.drag_item_size, self.drag_item_size)))
         drag.setHotSpot(QPoint(self.drag_item_size / 2, self.drag_item_size / 2))
         drag.exec_()
@@ -301,13 +299,12 @@ def filter_changed(self):
 
     def refresh_view(self):
         """Filter files with proxy class"""
+        model = self.model()
         filter_text = self.win.filesFilter.text()
-        self.files_model.proxy_model.setFilterRegExp(QRegExp(filter_text.replace(' ', '.*')))
-        self.files_model.proxy_model.setFilterCaseSensitivity(Qt.CaseInsensitive)
-        self.files_model.proxy_model.sort(Qt.AscendingOrder)
+        model.setFilterRegExp(QRegExp(filter_text.replace(' ', '.*'), Qt.CaseInsensitive))
 
-    def currentChanged(self, selected, deselected):
-        self.updateSelection()
+        col = model.sortColumn()
+        model.sort(col)
 
     def resize_contents(self):
         pass
@@ -333,7 +330,6 @@ def __init__(self, model, *args):
         self.setAcceptDrops(True)
         self.setDragEnabled(True)
         self.setDropIndicatorShown(True)
-        self.selected = []
         self.ignore_image_sequence_paths = []
 
         # Setup header columns and layout