Merge pull request #61 from bill350/master

Add fading animation for OverlayView by bill350

Author: nicolaschengdev

WYPopoverController/WYPopoverController.m

@@ -1613,6 +1613,7 @@ - (void)presentPopoverFromRect:(CGRect)aRect
     {
         if ((options & WYPopoverAnimationOptionFade) == WYPopoverAnimationOptionFade)
         {
+            overlayView.alpha = 0;
             containerView.alpha = 0;
         }
 
@@ -1626,6 +1627,8 @@ - (void)presentPopoverFromRect:(CGRect)aRect
         }
 
         [UIView animateWithDuration:WY_POPOVER_DEFAULT_ANIMATION_DURATION animations:^{
+            overlayView.alpha = 1;
+            overlayView.transform = CGAffineTransformIdentity;
             containerView.alpha = 1;
             containerView.transform = CGAffineTransformIdentity;
         } completion:^(BOOL finished) {
@@ -2027,8 +2030,20 @@ - (void)dismissPopoverAnimated:(BOOL)aAnimated callDelegate:(BOOL)callDelegate
 
     completionBlock = ^(BOOL finished) {
 
-        [overlayView removeFromSuperview];
-        overlayView = nil;
+        if (aAnimated)
+        {
+            [UIView animateWithDuration:WY_POPOVER_DEFAULT_ANIMATION_DURATION animations:^{
+                overlayView.alpha = 0;
+            } completion:^(BOOL finished) {
+                [overlayView removeFromSuperview];
+                overlayView = nil;
+            }];
+        }
+        else
+        {
+            [overlayView removeFromSuperview];
+            overlayView = nil;
+        }
 
         if ([viewController isKindOfClass:[UINavigationController class]] == NO)
         {