Prepare Dark Theme

Observe user interface theme change.

https://github.com/vector-im/riot-meta/issues/22

Riot/ViewController/RoomViewController.m

@@ -174,6 +174,9 @@
     
     // The search bar buttom item back up.
     UIBarButtonItem *searchBarButtonItem;
+    
+    // Observe kRiotDesignValuesDidChangeThemeNotification to handle user interface theme change.
+    id kRiotDesignValuesDidChangeThemeNotificationObserver;
 }
 
 @end
@@ -234,7 +237,6 @@
     [super finalizeInit];
     
     // Setup `MXKViewControllerHandling` properties
-    self.defaultBarTintColor = kRiotNavBarTintColor;
     self.enableBarTintColorStatusChange = NO;
     self.rageShakeManager = [RageShakeManager sharedManager];
     
@@ -402,6 +404,19 @@
     {
         [self refreshRoomInputToolbar];
     }
+    
+    // Observe user interface theme change.
+    kRiotDesignValuesDidChangeThemeNotificationObserver = [[NSNotificationCenter defaultCenter] addObserverForName:kRiotDesignValuesDidChangeThemeNotification object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *notif) {
+        
+        [self userInterfaceThemeDidChange];
+        
+    }];
+    [self userInterfaceThemeDidChange];
+}
+
+- (void)userInterfaceThemeDidChange
+{
+    self.defaultBarTintColor = kRiotSecondaryBgColor;
 }
 
 - (void)didReceiveMemoryWarning
@@ -1020,6 +1035,11 @@
     
     [self removeTypingNotificationsListener];
     
+    if (kRiotDesignValuesDidChangeThemeNotificationObserver)
+    {
+        [[NSNotificationCenter defaultCenter] removeObserver:kRiotDesignValuesDidChangeThemeNotificationObserver];
+        kRiotDesignValuesDidChangeThemeNotificationObserver = nil;
+    }
     if (kAppDelegateDidTapStatusBarNotificationObserver)
     {
         [[NSNotificationCenter defaultCenter] removeObserver:kAppDelegateDidTapStatusBarNotificationObserver];