Improve errors in the 'export with Signal' feature.

// FREEBIE

Signal/src/AppDelegate.m

@@ -268,30 +268,64 @@ static NSString *const kURLHostVerifyPrefix             = @"verify";
         NSString *filename = url.lastPathComponent;
         if ([filename stringByDeletingPathExtension].length < 1) {
             DDLogError(@"Application opened with URL invalid filename: %@", url);
+            [self showErrorAlertWithTitle:
+                      NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_TITLE",
+                          @"Title for the alert indicating the 'export with signal' attachment had an error.")
+                                  message:NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_INVALID_FILENAME",
+                                              @"Message for the alert indicating the 'export with signal' file had an "
+                                              @"invalid filename.")];
             return NO;
         }
         NSString *fileExtension = [filename pathExtension];
         if (fileExtension.length < 1) {
             DDLogError(@"Application opened with URL missing file extension: %@", url);
+            [self showErrorAlertWithTitle:
+                      NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_TITLE",
+                          @"Title for the alert indicating the 'export with signal' attachment had an error.")
+                                  message:NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_UNKNOWN_TYPE",
+                                              @"Message for the alert indicating the 'export with signal' file had "
+                                              @"unknown type.")];
             return NO;
         }
         NSString *utiType = [MIMETypeUtil utiTypeForFileExtension:fileExtension];
         if (utiType.length < 1) {
             DDLogError(@"Application opened with URL of unknown UTI type: %@", url);
+            [self showErrorAlertWithTitle:
+                      NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_TITLE",
+                          @"Title for the alert indicating the 'export with signal' attachment had an error.")
+                                  message:NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_UNKNOWN_TYPE",
+                                              @"Message for the alert indicating the 'export with signal' file had "
+                                              @"unknown type.")];
             return NO;
         }
         NSData *data = [NSData dataWithContentsOfURL:url];
         if (!data) {
             DDLogError(@"Application opened with URL with unloadable content: %@", url);
+            [self showErrorAlertWithTitle:
+                      NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_TITLE",
+                          @"Title for the alert indicating the 'export with signal' attachment had an error.")
+                                  message:NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_MISSING_DATA",
+                                              @"Message for the alert indicating the 'export with signal' data "
+                                              @"couldn't be loaded.")];
             return NO;
         }
         SignalAttachment *attachment = [SignalAttachment attachmentWithData:data dataUTI:utiType filename:filename];
         if (!attachment) {
             DDLogError(@"Application opened with URL with invalid content: %@", url);
+            [self showErrorAlertWithTitle:
+                      NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_TITLE",
+                          @"Title for the alert indicating the 'export with signal' attachment had an error.")
+                                  message:NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_MISSING_ATTACHMENT",
+                                              @"Message for the alert indicating the 'export with signal' attachment "
+                                              @"couldn't be loaded.")];
             return NO;
         }
         if ([attachment hasError]) {
             DDLogError(@"Application opened with URL with content error: %@ %@", url, [attachment errorName]);
+            [self showErrorAlertWithTitle:
+                      NSLocalizedString(@"EXPORT_WITH_SIGNAL_ERROR_TITLE",
+                          @"Title for the alert indicating the 'export with signal' attachment had an error.")
+                                  message:[attachment errorName]];
             return NO;
         }
         DDLogInfo(@"Application opened with URL: %@", url);
@@ -318,6 +352,19 @@ static NSString *const kURLHostVerifyPrefix             = @"verify";
     return NO;
 }
 
+- (void)showErrorAlertWithTitle:(NSString *)title message:(NSString *)message
+{
+    OWSAssert(title.length > 0);
+    OWSAssert(message.length > 0);
+
+    UIAlertController *controller =
+        [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
+
+    [controller addAction:[UIAlertAction actionWithTitle:NSLocalizedString(@"OK", nil)
+                                                   style:UIAlertActionStyleDefault
+                                                 handler:nil]];
+}
+
 - (void)applicationDidBecomeActive:(UIApplication *)application {
     DDLogWarn(@"%@ applicationDidBecomeActive.", self.tag);
 

Signal/src/ViewControllers/MessagesViewController.m

@@ -1025,7 +1025,7 @@ typedef enum : NSUInteger {
 {
     [self.collectionView.collectionViewLayout setMessageBubbleFont:[UIFont ows_dynamicTypeBodyFont]];
 
-    self.collectionView.showsVerticalScrollIndicator = NO;
+    self.collectionView.showsVerticalScrollIndicator = YES;
     self.collectionView.showsHorizontalScrollIndicator = NO;
 
     [self updateLoadEarlierVisible];

Signal/translations/en.lproj/Localizable.strings

@@ -94,9 +94,6 @@
 /* Attachment error message for attachments without any data */
 "ATTACHMENT_ERROR_MISSING_DATA" = "Attachment is empty.";
 
-/* Attachment error message for attachments with an invalid file format */
-"ATTACHMENT_ERROR_UNKNOWN_TYPE" = "Attachment is of invalid type";
-
 /* Accessibility hint describing what you can do with the attachment button */
 "ATTACHMENT_HINT" = "Choose or take a picture and then send it";
 
@@ -433,6 +430,21 @@
 /* during registration, embeds {{device type}}, e.g. \"iPhone\" or \"iPad\" */
 "EXISTING_USER_REGISTRATION_ALERT_TITLE" = "Activating this %@ will disable Signal on any other device currently associated with this phone number.";
 
+/* Message for the alert indicating the 'export with signal' file had an invalid filename. */
+"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_INVALID_FILENAME" = "Invalid filename.";
+
+/* Message for the alert indicating the 'export with signal' attachment couldn't be loaded. */
+"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_MISSING_ATTACHMENT" = "Couldn't load file.";
+
+/* Message for the alert indicating the 'export with signal' data couldn't be loaded. */
+"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_MISSING_DATA" = "Couldn't load file.";
+
+/* Message for the alert indicating the 'export with signal' file had unknown type. */
+"EXPORT_WITH_SIGNAL_ERROR_MESSAGE_UNKNOWN_TYPE" = "Unknown file type.";
+
+/* Title for the alert indicating the 'export with signal' attachment had an error. */
+"EXPORT_WITH_SIGNAL_ERROR_TITLE" = "Error";
+
 /* action sheet header when re-sending message which failed because of too many attempts */
 "FAILED_SENDING_BECAUSE_RATE_LIMIT" = "Too many failures with this contact. Please try again shortly.";