Animate the main toolbar when a device is connected/disconnected

Useful to indicate that the toolbar contents have changed

src/calibre/gui2/bars.py

@@ -9,11 +9,55 @@ __docformat__ = 'restructuredtext en'
 
 import sip
 from PyQt5.Qt import (
-    Qt, QAction, QMenu, QObject, QToolBar, QToolButton, QSize, pyqtSignal, QTimer)
+    Qt, QAction, QMenu, QObject, QToolBar, QToolButton, QSize, pyqtSignal,
+    QTimer, QPropertyAnimation, QEasingCurve, pyqtProperty, QPainter, QWidget)
 
 from calibre.constants import isosx
 from calibre.gui2.throbber import create_donate_widget
-from calibre.gui2 import gprefs, native_menubar_defaults
+from calibre.gui2 import gprefs, native_menubar_defaults, config
+
+class RevealBar(QWidget):  # {{{
+
+    def __init__(self, parent):
+        QWidget.__init__(self, parent)
+        self.setVisible(False)
+        self._animated_size = 1.0
+        self.animation = QPropertyAnimation(self, 'animated_size', self)
+        self.animation.setEasingCurve(QEasingCurve.Linear)
+        self.animation.setDuration(1000), self.animation.setStartValue(0.0), self.animation.setEndValue(1.0)
+        self.animation.valueChanged.connect(self.animation_value_changed)
+        self.animation.finished.connect(self.animation_done)
+
+    @pyqtProperty(float)
+    def animated_size(self):
+        return self._animated_size
+
+    @animated_size.setter
+    def animated_size(self, val):
+        self._animated_size = val
+
+    def animation_value_changed(self, *args):
+        self.update()
+
+    def animation_done(self):
+        self.setVisible(False)
+        self.update()
+
+    def start(self, bar):
+        self.setGeometry(bar.geometry())
+        self.setVisible(True)
+        self.animation.start()
+
+    def paintEvent(self, ev):
+        if self._animated_size < 1.0:
+            rect = self.rect()
+            painter = QPainter(self)
+            pal = self.palette()
+            col = pal.color(pal.Button)
+            rect.setLeft(rect.left() + (rect.width() * self._animated_size))
+            painter.setClipRect(rect)
+            painter.fillRect(self.rect(), col)
+# }}}
 
 class ToolBar(QToolBar):  # {{{
 
@@ -435,6 +479,7 @@ class BarsManager(QObject):
                 range(3)]
         self.main_bars = tuple(bars[:2])
         self.child_bars = tuple(bars[2:])
+        self.reveal_bar = RevealBar(parent)
 
         self.menu_bar = MenuBar(self.location_manager, self.parent())
         is_native_menubar = self.menu_bar.is_native_menubar
@@ -470,7 +515,7 @@ class BarsManager(QObject):
         for bar, actions in zip(self.bars, self.bar_actions[:3]):
             bar.init_bar(actions)
 
-    def update_bars(self):
+    def update_bars(self, reveal_bar=False):
         '''
         This shows the correct main toolbar and rebuilds the menubar based on
         whether a device is connected or not. Note that the toolbars are
@@ -486,6 +531,8 @@ class BarsManager(QObject):
             bar.update_lm_actions()
         if main_bar.added_actions:
             main_bar.setVisible(True)
+            if reveal_bar and not config['disable_animations']:
+                self.reveal_bar.start(main_bar)
         if child_bar.added_actions:
             child_bar.setVisible(True)
 

src/calibre/gui2/device.py

@@ -1078,7 +1078,7 @@ class DeviceMixin(object):  # {{{
             if self.current_view() != self.library_view:
                 self.book_details.reset_info()
             self.location_manager.update_devices()
-            self.bars_manager.update_bars()
+            self.bars_manager.update_bars(reveal_bar=True)
             self.library_view.set_device_connected(self.device_connected)
             # Empty any device view information
             self.memory_view.set_database([])
@@ -1096,7 +1096,7 @@ class DeviceMixin(object):  # {{{
         info, cp, fs = job.result
         self.location_manager.update_devices(cp, fs,
                 self.device_manager.device.icon)
-        self.bars_manager.update_bars()
+        self.bars_manager.update_bars(reveal_bar=True)
         self.status_bar.device_connected(info[0])
         db = self.current_db
         self.device_manager.set_library_information(None, os.path.basename(db.library_path),