Animate sending icon.

Signal/src/ViewControllers/ConversationView/Cells/OWSMessageBubbleView.m

@@ -1270,6 +1270,7 @@ NS_ASSUME_NONNULL_BEGIN
     [self.bubbleStrokeView removeFromSuperview];
 
     [self.footerView removeFromSuperview];
+    [self.footerView prepareForReuse];
 
     for (UIView *subview in self.stackView.subviews) {
         [subview removeFromSuperview];

Signal/src/ViewControllers/ConversationView/Cells/OWSMessageFooterView.h

@@ -12,6 +12,8 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (CGSize)measureWithConversationViewItem:(ConversationViewItem *)viewItem;
 
+- (void)prepareForReuse;
+
 @end
 
 NS_ASSUME_NONNULL_END

Signal/src/ViewControllers/ConversationView/Cells/OWSMessageFooterView.m

@@ -5,6 +5,7 @@
 #import "OWSMessageFooterView.h"
 #import "DateUtil.h"
 #import "Signal-Swift.h"
+#import <QuartzCore/QuartzCore.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -114,6 +115,7 @@ NS_ASSUME_NONNULL_BEGIN
             case MessageReceiptStatusUploading:
             case MessageReceiptStatusSending:
                 statusIndicatorImage = [UIImage imageNamed:@"message_status_sending"];
+                [self animateSpinningIcon];
                 break;
             case MessageReceiptStatusSent:
             case MessageReceiptStatusSkipped:
@@ -146,6 +148,19 @@ NS_ASSUME_NONNULL_BEGIN
     }
 }
 
+- (void)animateSpinningIcon
+{
+    CABasicAnimation *animation;
+    animation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
+    animation.toValue = @(M_PI * 2.0);
+    const CGFloat kPeriodSeconds = 1.f;
+    animation.duration = kPeriodSeconds;
+    animation.cumulative = YES;
+    animation.repeatCount = HUGE_VALF;
+
+    [self.statusIndicatorImageView.layer addAnimation:animation forKey:@"animation"];
+}
+
 - (void)configureLabelsWithConversationViewItem:(ConversationViewItem *)viewItem
 {
     OWSAssert(viewItem);
@@ -184,6 +199,11 @@ NS_ASSUME_NONNULL_BEGIN
     return statusMessage;
 }
 
+- (void)prepareForReuse
+{
+    [self.statusIndicatorImageView.layer removeAllAnimations];
+}
+
 @end
 
 NS_ASSUME_NONNULL_END