tracklist: Add a Selection OSD to the TrackView

The OSD will eventually contain buttons for modifying playlists, but for
now it just has functions and properties for mananging the current track
selection.

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

emmental/tracklist/selection.py

@@ -0,0 +1,31 @@
+# Copyright 2023 (c) Anna Schumaker.
+"""An OSD to show when tracks are selected."""
+from gi.repository import GObject
+from gi.repository import Gtk
+from .. import playlist
+
+
+class OSD(Gtk.Overlay):
+    """An Overlay with extra controls for the Tracklist."""
+
+    playlist = GObject.Property(type=playlist.playlist.Playlist)
+    selection = GObject.Property(type=Gtk.SelectionModel)
+
+    have_selected = GObject.Property(type=bool, default=False)
+    n_selected = GObject.Property(type=int)
+
+    def __init__(self, selection: Gtk.SelectionModel, **kwargs):
+        """Initialize an OSD."""
+        super().__init__(selection=selection, **kwargs)
+
+        self.selection.connect("selection-changed", self.__selection_changed)
+
+    def __selection_changed(self, selection: Gtk.SelectionModel,
+                            position: int, n_items: int) -> None:
+        self.n_selected = selection.get_selection().get_size()
+        self.have_selected = self.n_selected > 0
+
+    def clear_selection(self, *args) -> None:
+        """Clear the current selection."""
+        self.selection.unselect_all()
+        self.__selection_changed(self.selection, 0, 0)

emmental/tracklist/trackview.py

@@ -7,6 +7,7 @@ from .. import db
 from .. import factory
 from .. import playlist
 from . import row
+from . import selection
 
 
 class TrackView(Gtk.Frame):
@@ -16,6 +17,9 @@ class TrackView(Gtk.Frame):
     n_tracks = GObject.Property(type=int)
     runtime = GObject.Property(type=float)
 
+    n_selected = GObject.Property(type=int)
+    have_selected = GObject.Property(type=bool, default=False)
+
     def __init__(self, sql: db.Connection, **kwargs):
         """Initialize a TrackView."""
         super().__init__(**kwargs)
@@ -27,6 +31,7 @@ class TrackView(Gtk.Frame):
                                           enable_rubberband=True,
                                           model=self._selection)
         self._scrollwin = Gtk.ScrolledWindow(child=self._columnview)
+        self._osd = selection.OSD(self._selection, child=self._scrollwin)
 
         self.__append_column("Art", "cover", row.AlbumCover, resizable=False)
         self.__append_column("Fav", "favorite", row.FavoriteButton,
@@ -52,13 +57,16 @@ class TrackView(Gtk.Frame):
         self.__append_column("Filepath", "path", row.PathString, visible=False)
 
         self.bind_property("playlist", self._filtermodel, "model")
+        self.bind_property("playlist", self._osd, "playlist")
+        self._osd.bind_property("have-selected", self, "have-selected")
+        self._osd.bind_property("n-selected", self, "n-selected")
         self._selection.bind_property("n-items", self, "n-tracks")
 
         self._selection.connect("items-changed", self.__runtime_changed)
         self._columnview.connect("activate", self.__track_activated)
         self._columnview.add_css_class("emmental-track-list")
 
-        self.set_child(self._scrollwin)
+        self.set_child(self._osd)
 
     def __append_column(self, title: str, property: str, row_type: type,
                         *, width: int = -1, visible: bool = True,
@@ -87,6 +95,10 @@ class TrackView(Gtk.Frame):
                 pos = max(i - 3, 0) * adjustment.get_upper()
                 adjustment.set_value(pos / self._selection.get_n_items())
 
+    def clear_selected_tracks(self) -> None:
+        """Clear the currently selected tracks."""
+        self._osd.clear_selection()
+
     @GObject.Property(type=Gio.ListModel)
     def columns(self) -> Gio.ListModel:
         """Get the ListModel for the columns."""

tests/tracklist/test_selection.py

@@ -0,0 +1,49 @@
+# Copyright 2023 (c) Anna Schumaker.
+"""Tests our Tracklist Selection OSD."""
+import emmental.buttons
+import emmental.tracklist.selection
+import tests.util
+from gi.repository import Gtk
+
+
+class TestOsd(tests.util.TestCase):
+    """Test the Tracklist OSD."""
+
+    def setUp(self):
+        """Set up common variables."""
+        super().setUp()
+        self.db_plist = self.sql.playlists.create("Test Playlist")
+        self.playlist = emmental.playlist.playlist.Playlist(self.sql,
+                                                            self.db_plist)
+        self.model = Gtk.StringList.new(["Test", "OSD", "Strings"])
+        self.selection = Gtk.MultiSelection(model=self.model)
+        self.osd = emmental.tracklist.selection.OSD(self.selection)
+
+    def test_init(self):
+        """Test that the OSD is set up properly."""
+        self.assertIsInstance(self.osd, Gtk.Overlay)
+
+        self.assertEqual(self.osd.selection, self.selection)
+        self.assertIsNone(self.osd.playlist)
+
+    def test_selection_properties(self):
+        """Test updating properties when the selection changes."""
+        self.assertFalse(self.osd.have_selected)
+        self.assertEqual(self.osd.n_selected, 0)
+
+        self.selection.select_item(1, True)
+        self.assertTrue(self.osd.have_selected)
+        self.assertEqual(self.osd.n_selected, 1)
+
+    def test_clear_selection(self):
+        """Test the clear_selection() function."""
+        self.selection.select_item(1, True)
+        self.osd.clear_selection()
+        self.assertEqual(self.selection.get_selection().get_size(), 0)
+        self.assertEqual(self.osd.n_selected, 0)
+        self.assertFalse(self.osd.have_selected)
+
+        self.osd.playlist = self.playlist
+        self.assertEqual(self.selection.get_selection().get_size(), 0)
+        self.assertEqual(self.osd.n_selected, 0)
+        self.assertFalse(self.osd.have_selected)

tests/tracklist/test_trackview.py

@@ -30,8 +30,12 @@ class TestTrackView(tests.util.TestCase):
         """Test that the TrackView is initialized properly."""
         self.assertIsInstance(self.trackview, Gtk.Frame)
         self.assertIsInstance(self.trackview._scrollwin, Gtk.ScrolledWindow)
+        self.assertIsInstance(self.trackview._osd,
+                              emmental.tracklist.selection.OSD)
 
-        self.assertEqual(self.trackview.get_child(), self.trackview._scrollwin)
+        self.assertEqual(self.trackview.get_child(), self.trackview._osd)
+        self.assertEqual(self.trackview._osd.get_child(),
+                         self.trackview._scrollwin)
         self.assertEqual(self.trackview._scrollwin.get_child(),
                          self.trackview._columnview)
 
@@ -76,12 +80,20 @@ class TestTrackView(tests.util.TestCase):
             requested.assert_called_with(self.playlist, self.track)
             mock_unselect.assert_called()
 
+    def test_clear_selected_tracks(self):
+        """Test the clear_selected_tracks() function."""
+        with unittest.mock.patch.object(self.trackview._osd,
+                                        "clear_selection") as mock_clear:
+            self.trackview.clear_selected_tracks()
+            mock_clear.assert_called()
+
     def test_playlist(self):
         """Test the playlist property."""
         self.assertIsNone(self.trackview.playlist)
         self.trackview.playlist = self.playlist
         self.assertEqual(self.trackview._filtermodel.get_model(),
                          self.playlist)
+        self.assertEqual(self.trackview._osd.playlist, self.playlist)
 
     def test_n_tracks(self):
         """Test the n-tracks property."""
@@ -97,6 +109,17 @@ class TestTrackView(tests.util.TestCase):
         self.db_plist.add_track(self.track)
         self.assertEqual(self.trackview.runtime, 10.0)
 
+    def test_n_selected(self):
+        """Test the n-selected and have-selected properties."""
+        self.assertEqual(self.trackview.n_selected, 0)
+        self.assertFalse(self.trackview.have_selected)
+
+        self.trackview._osd.n_selected = 4
+        self.trackview._osd.have_selected = True
+
+        self.assertEqual(self.trackview.n_selected, 4)
+        self.assertTrue(self.trackview.have_selected)
+
 
 class TestTrackViewColumns(tests.util.TestCase):
     """Test the TrackView Columns."""