Prevent the cover browser from being refreshed and therefore using resources when it is hidden

src/calibre/gui2/actions/add.py

@@ -272,8 +272,7 @@ class AddAction(InterfaceAction):
                     fmts = [pt.name]
                 ids.append(db.import_book(mi, fmts))
             self.gui.library_view.model().books_added(num)
-            if hasattr(self.gui, 'db_images'):
+            self.gui.refresh_cover_browser()
-                self.gui.db_images.beginResetModel(), self.gui.db_images.endResetModel()
             self.gui.tags_view.recount()
             if ids:
                 ids.reverse()
@@ -374,8 +373,7 @@ class AddAction(InterfaceAction):
         if current_idx.isValid():
             self.gui.library_view.model().current_changed(current_idx, current_idx)
         if cover_changed:
-            if self.gui.cover_flow:
+            self.gui.refresh_cover_browser()
-                self.gui.cover_flow.dataChanged()
 
     def __add_filesystem_book(self, paths, allow_device=True):
         if isinstance(paths, basestring):
@@ -440,8 +438,7 @@ class AddAction(InterfaceAction):
         if adder.number_of_books_added > 0:
             self.gui.library_view.model().books_added(adder.number_of_books_added)
             self.gui.library_view.set_current_row(0)
-            if hasattr(self.gui, 'db_images'):
+            self.gui.refresh_cover_browser()
-                self.gui.db_images.beginResetModel(), self.gui.db_images.endResetModel()
             self.gui.tags_view.recount()
 
         if adder.merged_books:

src/calibre/gui2/actions/edit_metadata.py

@@ -333,8 +333,7 @@ class EditMetadataAction(InterfaceAction):
         m = self.gui.library_view.model()
         m.refresh_ids(list(book_ids))
         current = self.gui.library_view.currentIndex()
-        if self.gui.cover_flow:
+        self.gui.refresh_cover_browser()
-            self.gui.cover_flow.dataChanged()
         m.current_changed(current, previous or current)
         self.gui.tags_view.recount()
 
@@ -401,8 +400,7 @@ class EditMetadataAction(InterfaceAction):
             else:
                 m.refresh_ids(refresh_books)
             self.gui.tags_view.recount()
-            if self.gui.cover_flow:
+            self.gui.refresh_cover_browser()
-                self.gui.cover_flow.dataChanged()
             self.gui.library_view.select_rows(book_ids)
 
     # Merge books {{{
@@ -755,8 +753,8 @@ class EditMetadataAction(InterfaceAction):
             cr = self.gui.library_view.currentIndex().row()
             self.gui.library_view.model().refresh_ids(
                 list(book_ids), cr)
-            if covers_changed and self.gui.cover_flow:
+            if covers_changed:
-                self.gui.cover_flow.dataChanged()
+                self.gui.refresh_cover_browser()
             if tag_browser_changed:
                 self.gui.tags_view.recount()
 

src/calibre/gui2/auto_add.py

@@ -260,8 +260,7 @@ class AutoAdder(QObject):
             gui.status_bar.show_message(_(
                 'Added %(num)d book(s) automatically from %(src)s') %
                 dict(num=count, src=self.worker.path), 2000)
-            if hasattr(gui, 'db_images'):
+            gui.refresh_cover_browser()
-                gui.db_images.beginResetModel(), gui.db_images.endResetModel()
 
         if needs_rescan:
             QTimer.singleShot(2000, self.dir_changed)

src/calibre/gui2/cover_flow.py

@@ -78,9 +78,10 @@ if pictureflow is not None:
 
     class DatabaseImages(pictureflow.FlowImages):
 
-        def __init__(self, model, buffer=20):
+        def __init__(self, model, is_cover_browser_visible):
             pictureflow.FlowImages.__init__(self)
             self.model = model
+            self.is_cover_browser_visible = is_cover_browser_visible
             self.model.modelReset.connect(self.reset, type=Qt.QueuedConnection)
 
         def count(self):
@@ -108,7 +109,8 @@ if pictureflow is not None:
             self.beginResetModel(), self.endResetModel()
 
         def beginResetModel(self):
-            self.dataChanged.emit()
+            if self.is_cover_browser_visible():
+                self.dataChanged.emit()
 
         def endResetModel(self):
             pass
@@ -244,9 +246,8 @@ class CoverFlowMixin(object):
             self.cover_flow = CoverFlow(parent=self)
             self.cover_flow.currentChanged.connect(self.sync_listview_to_cf)
             self.cover_flow.context_menu_requested.connect(self.cf_context_menu_requested)
-            self.library_view.selectionModel().currentRowChanged.connect(
+            self.library_view.selectionModel().currentRowChanged.connect(self.sync_cf_to_listview)
-                    self.sync_cf_to_listview)
+            self.db_images = DatabaseImages(self.library_view.model(), self.is_cover_browser_visible)
-            self.db_images = DatabaseImages(self.library_view.model())
             self.cover_flow.setImages(self.db_images)
             self.cover_flow.itemActivated.connect(self.iactions['View'].view_specific_book)
         else:
@@ -254,6 +255,7 @@ class CoverFlowMixin(object):
                                      '<br>'+pictureflowerror)
             self.cover_flow.setWordWrap(True)
         if config['separate_cover_flow']:
+            self.separate_cover_browser = True
             self.cb_splitter.button.clicked.connect(self.toggle_cover_browser)
             self.cb_splitter.button.set_state_to_show()
             self.cb_splitter.action_toggle.triggered.connect(self.toggle_cover_browser)
@@ -261,6 +263,7 @@ class CoverFlowMixin(object):
                 self.cover_flow.stop.connect(self.hide_cover_browser)
             self.cover_flow.setVisible(False)
         else:
+            self.separate_cover_browser = False
             self.cb_splitter.insertWidget(self.cb_splitter.side_index, self.cover_flow)
             if CoverFlow is not None:
                 self.cover_flow.stop.connect(self.cb_splitter.hide_side_pane)
@@ -321,9 +324,23 @@ class CoverFlowMixin(object):
             self.cb_dialog = None
         self.cb_splitter.button.set_state_to_show()
 
+    def is_cover_browser_visible(self):
+        try:
+            if self.separate_cover_browser:
+                return self.cover_flow.isVisible()
+        except AttributeError:
+            return False  # called before init_cover_flow_mixin
+        return not self.cb_splitter.is_side_index_hidden
+
+    def refresh_cover_browser(self):
+        try:
+            if self.is_cover_browser_visible() and not isinstance(self.cover_flow, QLabel):
+                self.cover_flow.dataChanged()
+        except AttributeError:
+            pass  # called before init_cover_flow_mixin
+
     def sync_cf_to_listview(self, current, previous):
-        if self.cover_flow_sync_flag and self.cover_flow.isVisible() and \
+        if (self.cover_flow_sync_flag and self.is_cover_browser_visible() and self.cover_flow.currentSlide() != current.row()):
-                self.cover_flow.currentSlide() != current.row():
             self.cover_flow.setCurrentSlide(current.row())
         self.cover_flow_sync_flag = True
 
@@ -338,8 +355,7 @@ class CoverFlowMixin(object):
     def cover_flow_do_sync(self):
         self.cover_flow_sync_flag = True
         try:
-            if self.cover_flow.isVisible() and self.cf_last_updated_at is not None and \
+            if (self.is_cover_browser_visible() and self.cf_last_updated_at is not None and time.time() - self.cf_last_updated_at > 0.5):
-                time.time() - self.cf_last_updated_at > 0.5:
                 self.cf_last_updated_at = None
                 row = self.cover_flow.currentSlide()
                 m = self.library_view.model()

src/calibre/gui2/dialogs/book_info.py

@@ -130,8 +130,7 @@ class BookInfo(QDialog):
         if self.current_row is not None:
             id_ = self.view.model().id(self.current_row)
             self.view.model().db.set_cover(id_, data)
-        if self.gui.cover_flow:
+        self.gui.refresh_cover_browser()
-            self.gui.cover_flow.dataChanged()
         ci = self.view.currentIndex()
         if ci.isValid():
             self.view.model().current_changed(ci, ci)

src/calibre/gui2/init.py

@@ -528,8 +528,7 @@ class LayoutMixin(object):  # {{{
 
     def bd_cover_changed(self, id_, cdata):
         self.library_view.model().db.set_cover(id_, cdata)
-        if self.cover_flow:
+        self.refresh_cover_browser()
-            self.cover_flow.dataChanged()
 
     def bd_open_cover_with(self, book_id, entry):
         cpath = self.current_db.new_api.format_abspath(book_id, '__COVER_INTERNAL__')
@@ -560,8 +559,7 @@ class LayoutMixin(object):  # {{{
     def bd_cover_removed(self, id_):
         self.library_view.model().db.remove_cover(id_, commit=True,
                 notify=False)
-        if self.cover_flow:
+        self.refresh_cover_browser()
-            self.cover_flow.dataChanged()
 
     def bd_copy_link(self, url):
         if url:

src/calibre/gui2/preferences/look_feel.py

@@ -470,9 +470,8 @@ class ConfigWidget(ConfigWidgetBase, Ui_Form):
         self.update_font_display()
         gui.tags_view.reread_collapse_parameters()
         gui.library_view.refresh_book_details()
-        if hasattr(gui.cover_flow, 'setShowReflections'):
+        gui.cover_flow.setShowReflections(gprefs['cover_browser_reflections'])
-            gui.cover_flow.setShowReflections(gprefs['cover_browser_reflections'])
+        gui.cover_flow.setPreserveAspectRatio(gprefs['cb_preserve_aspect_ratio'])
-            gui.cover_flow.setPreserveAspectRatio(gprefs['cb_preserve_aspect_ratio'])
         gui.library_view.refresh_row_sizing()
         gui.grid_view.refresh_settings()
 

src/calibre/gui2/ui.py

@@ -87,7 +87,7 @@ _gui = None
 def get_gui():
     return _gui
 
-def add_quick_start_guide(library_view, db_images):
+def add_quick_start_guide(library_view, refresh_cover_browser=None):
     from calibre.ebooks.metadata.meta import get_metadata
     from calibre.ebooks import calibre_cover
     from calibre.utils.zipfile import safe_replace
@@ -112,8 +112,8 @@ def add_quick_start_guide(library_view, db_images):
     library_view.model().add_books([tmp.name], ['epub'], [mi])
     os.remove(tmp.name)
     library_view.model().books_added(1)
-    if hasattr(db_images, 'reset'):
+    if refresh_cover_browser is not None:
-        db_images.reset()
+        refresh_cover_browser()
     if library_view.model().rowCount(None) < 3:
         library_view.resizeColumnsToContents()
 
@@ -342,7 +342,7 @@ class Main(MainWindow, MainWindowMixin, DeviceMixin, EmailMixin,  # {{{
                 self.iactions['Choose Library'].count_changed)
         if not gprefs.get('quick_start_guide_added', False):
             try:
-                add_quick_start_guide(self.library_view, getattr(self, 'db_images', None))
+                add_quick_start_guide(self.library_view)
             except:
                 import traceback
                 traceback.print_exc()