Add warning before sending group message invites.

Signal/src/ViewControllers/InviteFlow.swift

@@ -169,7 +169,21 @@ class InviteFlow: NSObject, MFMessageComposeViewControllerDelegate, MFMailCompos
 
     public func dismissAndSendSMSTo(phoneNumbers: [String]) {
         self.presentingViewController.dismiss(animated: true) {
-            self.sendSMSTo(phoneNumbers: phoneNumbers)
+            if phoneNumbers.count > 0 {
+                let warning = UIAlertController(title: nil,
+                                                message: NSLocalizedString("INVITE_WARNING_MULTIPLE_INVITES_BY_TEXT",
+                                                                                       comment: "Alert warning that sending an invite to multiple users will create a group message whose recipients will be able to see each other."),
+                                                preferredStyle: .alert)
+                warning.addAction(UIAlertAction(title: NSLocalizedString("BUTTON_CONTINUE",
+                                                                         comment: "Label for 'continue' button."),
+                                                style: .default, handler: { _ in
+                    self.sendSMSTo(phoneNumbers: phoneNumbers)
+                }))
+                warning.addAction(OWSAlerts.cancelAction)
+                self.presentingViewController.present(warning, animated: true, completion: nil)
+            } else {
+                self.sendSMSTo(phoneNumbers: phoneNumbers)
+            }
         }
     }
 

Signal/translations/az_AZ.lproj/Localizable.strings

@@ -280,6 +280,9 @@
 /* Button text to enable batch selection mode */
 "BUTTON_SELECT" = "Select";
 
+/* Button text to enable batch selection mode */
+"BUTTON_CONTINUE" = "Continue";
+
 /* Alert message when calling and permissions for microphone are missing */
 "CALL_AUDIO_PERMISSION_MESSAGE" = "Signal requires access to your microphone to make calls and record voice messages. You can grant this permission in the Settings app.";
 

Signal/translations/en.lproj/Localizable.strings

@@ -274,6 +274,9 @@
 /* Title format for action sheet that offers to block an unknown user.Embeds {{the unknown user's name or phone number}}. */
 "BLOCK_OFFER_ACTIONSHEET_TITLE_FORMAT" = "Block %@?";
 
+/* Label for 'continue' button. */
+"BUTTON_CONTINUE" = "Continue";
+
 /* Label for generic done button. */
 "BUTTON_DONE" = "Done";
 
@@ -794,6 +797,9 @@
 /* Call setup status label */
 "END_CALL_UNCATEGORIZED_FAILURE" = "Call Failed.";
 
+/* Error indicating that the phone's contacts could not be retrieved. */
+"ERROR_COULD_NOT_FETCH_CONTACTS" = "ERROR_COULD_NOT_FETCH_CONTACTS";
+
 /* Generic notice when message failed to send. */
 "ERROR_DESCRIPTION_CLIENT_SENDING_FAILURE" = "Failed to send message.";
 
@@ -1040,6 +1046,9 @@
 /* Navbar title */
 "INVITE_FRIENDS_PICKER_TITLE" = "Invite Friends";
 
+/* Alert warning that sending an invite to multiple users will create a group message whose recipients will be able to see each other. */
+"INVITE_WARNING_MULTIPLE_INVITES_BY_TEXT" = "Inviting multiple users at the same time will send a group message whose recipients will be able to see each other.";
+
 /* Slider label embeds {{TIME_AMOUNT}}, e.g. '2 hours'. See *_TIME_AMOUNT strings for examples. */
 "KEEP_MESSAGES_DURATION" = "Messages disappear after %@.";