sidebar: Create a Stack with pages

Additionally, we save the current page when it is changed and restore on
startup.

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

sidebar/stack.py

@@ -0,0 +1,37 @@
+# Copyright 2021 (c) Anna Schumaker.
+import db
+import lib
+from gi.repository import GObject
+from gi.repository import Gtk
+from . import view
+
+class Stack(Gtk.Stack):
+    def __init__(self):
+        Gtk.Stack.__init__(self)
+        self.set_transition_type(Gtk.StackTransitionType.OVER_UP_DOWN)
+        self.set_vexpand(True)
+
+        self.add_page(db.user.Table, "Playlists", "audio-x-generic")
+        self.add_page(db.artist.Table, "Artists", "avatar-default-symbolic")
+        self.add_page(db.genre.Table, "Genres", "emblem-generic")
+        self.add_page(db.decade.Table, "Decades", "x-office-calendar")
+        self.add_page(db.library.Table, "Libraries", "folder-music")
+
+        lib.settings.initialize("sidebar.page", "Playlists")
+        self.set_visible_child_name(lib.settings.get("sidebar.page"))
+        self.connect("notify::visible-child-name", self.change_page)
+
+    def add_page(self, table, name, icon):
+        window = view.TableWindow(table)
+        self.add_named(window, name).set_icon_name(icon)
+        window.get_selection().connect("selection-changed", self.selection_changed)
+
+    def change_page(self, stack, param):
+        lib.settings.set("sidebar.page", self.get_visible_child_name())
+        self.emit("playlist-changed", self.get_visible_child().get_selected_playlist())
+
+    def selection_changed(self, selection, pos, n_items):
+        self.emit("playlist-changed", selection.get_selected_playlist())
+
+    @GObject.Signal(arg_types=(db.playlist.Playlist,))
+    def playlist_changed(self, plist): pass

sidebar/test_stack.py

@@ -0,0 +1,75 @@
+# Copyright 2021 (c) Anna Schumaker.
+import db
+import lib
+import unittest
+from gi.repository import Gtk
+from . import stack
+from . import view
+
+class TestStack(unittest.TestCase):
+    def playlist_changed(self, stack, playlist):
+        self.changed = playlist
+
+    def test_init(self):
+        s = stack.Stack()
+        self.assertIsInstance(s, Gtk.Stack)
+        self.assertTrue(s.get_vexpand())
+        self.assertEqual(s.get_transition_type(),
+                         Gtk.StackTransitionType.OVER_UP_DOWN)
+
+    def test_pages(self):
+        s = stack.Stack()
+ 
+        child = s.get_child_by_name("Playlists")
+        self.assertIsInstance(child, view.TableWindow)
+        self.assertEqual(child.get_table(), db.user.Table)
+        self.assertEqual(s.get_page(child).get_icon_name(), "audio-x-generic")
+
+        child = s.get_child_by_name("Artists")
+        self.assertIsInstance(child, view.TableWindow)
+        self.assertEqual(child.get_table(), db.artist.Table)
+        self.assertEqual(s.get_page(child).get_icon_name(), "avatar-default-symbolic")
+
+        child = s.get_child_by_name("Genres")
+        self.assertIsInstance(child, view.TableWindow)
+        self.assertEqual(child.get_table(), db.genre.Table)
+        self.assertEqual(s.get_page(child).get_icon_name(), "emblem-generic")
+
+        child = s.get_child_by_name("Decades")
+        self.assertIsInstance(child, view.TableWindow)
+        self.assertEqual(child.get_table(), db.decade.Table)
+        self.assertEqual(s.get_page(child).get_icon_name(), "x-office-calendar")
+
+        child = s.get_child_by_name("Libraries")
+        self.assertIsInstance(child, view.TableWindow)
+        self.assertEqual(child.get_table(), db.library.Table)
+        self.assertEqual(s.get_page(child).get_icon_name(), "folder-music")
+
+    def test_change_page(self):
+        lib.settings.reset()
+        genre = db.genre.Table.find("Test Genre")
+        s = stack.Stack()
+        s.connect("playlist-changed", self.playlist_changed)
+
+        self.assertEqual(lib.settings.get("sidebar.page"), "Playlists")
+        self.assertEqual(s.get_visible_child_name(), "Playlists")
+        s.set_visible_child(s.get_child_by_name("Genres"))
+        self.assertEqual(lib.settings.get("sidebar.page"), "Genres")
+        self.assertEqual(self.changed, genre)
+
+        s2 = stack.Stack()
+        self.assertEqual(s2.get_visible_child_name(), "Genres")
+
+    def test_change_selected(self):
+        g1 = db.genre.Table.find("Test Genre")
+        g2 = db.genre.Table.find("Test Genre 2")
+        s = stack.Stack()
+
+        child = s.get_child_by_name("Genres")
+        s.set_visible_child(child)
+        s.connect("playlist-changed", self.playlist_changed)
+
+        child.get_selection().set_selected(1)
+        self.assertEqual(self.changed, g2)
+        child.get_selection().set_selected(0)
+        self.assertEqual(self.changed, g1)