Merge lp:~ahayzen/cappella/cappella10_properties_load_in_thread into lp:cappella

[Andrew Hayzen]

* Properties data is now loaded in separate thread

[Andrew Hayzen (ahayzen)]

review: Approve

=== modified file 'cappella/gui/widget/properties.py'
--- cappella/gui/widget/properties.py	2013-04-02 22:48:35 +0000
+++ cappella/gui/widget/properties.py	2013-04-29 15:18:26 +0000
@@ -20,6 +20,7 @@
 
 from gi.repository import GdkPixbuf, GObject, Gtk
 from os.path import getsize
+from threading import current_thread, Lock, Thread
 from urllib.request import urlopen
 
 from ...config.cappella import settings
@@ -37,6 +38,7 @@
     def __init__(self, uri, library):
         self.album_art_helper = AlbumArtHelper()
         self.library = library
+        self.lock = Lock()
         self.uri = uri
         self.ids = []
 
@@ -50,13 +52,9 @@
         if is_media(uri):
             self.do_build_window()
 
-            self.do_load_box_top()
-
-            self.do_load_box_bottom()
-
-            self.do_load_read_only()
-
-            self.on_changed_change()
+            self.thread = Thread(target=self.load)
+            self.thread.daemon = True
+            self.thread.start()
 
             #-------------------------------------------------- Connect signals
             idn = signal.connect("_musicengine_start_int_",
@@ -442,15 +440,36 @@
         signal.emit("_library_change_", self.library, self.uri, info)
 
         # Reload properties window
-        self.do_load_box_top()
-
-        self.do_load_box_bottom()
-
-        self.do_load_read_only()
-
         self.changed = False  # reset changed
 
-        self.on_changed_change()  # Update save button
+        self.thread = Thread(target=self.load)
+        self.thread.daemon = True
+        self.thread.start()
+
+        return True
+
+    def load(self):
+        """
+        Load the data into the view
+        Only run next stage if previous passes
+        """
+
+        self.lock.acquire()
+
+        if self.load_safe(self.do_load_box_top):
+            if self.load_safe(self.do_load_box_bottom):
+                if self.load_safe(self.do_load_read_only):
+                    if self.load_safe(self.on_changed_change):
+                        self.lock.release()
+
+    def load_safe(self, method):
+        """ Load the section but stop if a new thread has been started """
+
+        if self.thread != current_thread():
+            self.lock.release()
+            return False
+
+        method()
 
         return True
 
@@ -477,15 +496,11 @@
         self.uri, self.library = data  # Set new data
 
         # Reload properties window
-        self.do_load_box_top()
-
-        self.do_load_box_bottom()
-
-        self.do_load_read_only()
-
         self.changed = False  # reset changed
 
-        self.on_changed_change()  # update save button
+        self.thread = Thread(target=self.load)
+        self.thread.daemon = True
+        self.thread.start()
 
     def on_button_previous(self, *args):
         """ Select previous file for properties window """
@@ -510,15 +525,11 @@
         self.uri, self.library = data  # Set new data
 
         # Reload properties window
-        self.do_load_box_top()
-
-        self.do_load_box_bottom()
-
-        self.do_load_read_only()
-
         self.changed = False  # reset changed
 
-        self.on_changed_change()  # update save button
+        self.thread = Thread(target=self.load)
+        self.thread.daemon = True
+        self.thread.start()
 
     def on_changed_change(self):
         """ Update saved button state """