Prepopulate caption field with URL.

SignalMessaging/attachments/AttachmentApprovalViewController.swift

@@ -129,7 +129,9 @@ public class AttachmentApprovalViewController: OWSViewController, CaptioningTool
 
         scrollView.autoPinEdgesToSuperviewEdges()
 
-        let backgroundColor = UIColor.black
+        let defaultCaption = self.defaultCaption()
+        let isUrlShare = defaultCaption != nil
+        let backgroundColor = isUrlShare ? UIColor.ows_signalBrandBlue : UIColor.black
         self.view.backgroundColor = backgroundColor
 
         // Create full screen container view so the scrollView
@@ -168,9 +170,7 @@ public class AttachmentApprovalViewController: OWSViewController, CaptioningTool
         topToolbar.items = [cancelButton]
 
         // Bottom Toolbar
-        //
-        // Don't add a caption to text messages.
-        let captioningToolbar = CaptioningToolbar(allowCaptions:!self.attachment.isOversizeText)
+        let captioningToolbar = CaptioningToolbar(defaultCaption:defaultCaption)
         captioningToolbar.captioningToolbarDelegate = self
         self.bottomToolbar = captioningToolbar
 
@@ -236,6 +236,18 @@ public class AttachmentApprovalViewController: OWSViewController, CaptioningTool
         self.pauseVideo()
     }
 
+    private func defaultCaption() -> String? {
+        guard self.attachment.isUrl else {
+            return nil
+        }
+        let data = self.attachment.data
+        guard let messageText = String(data: data, encoding: String.Encoding.utf8) else {
+            Logger.error("\(self.logTag) Couldn't load url strubg")
+            return nil
+        }
+        return messageText
+    }
+
     override public var inputAccessoryView: UIView? {
         self.bottomToolbar.layoutIfNeeded()
         return self.bottomToolbar
@@ -559,7 +571,6 @@ class CaptioningToolbar: UIView, UITextViewDelegate {
     private let sendButton: UIButton
     private let textView: UITextView
     private let bottomGradient: GradientView
-    private let allowCaptions: Bool
 
     // Layout Constants
     var maxTextViewHeight: CGFloat {
@@ -590,12 +601,11 @@ class CaptioningToolbar: UIView, UITextViewDelegate {
     }
 
     let kSendButtonShadowOffset: CGFloat = 1
-    init(allowCaptions: Bool) {
+    init(defaultCaption: String?) {
         self.sendButton = UIButton(type: .system)
         self.bottomGradient = GradientView(from: UIColor.clear, to: UIColor.black)
         self.textView =  MessageTextView()
         self.textViewHeight = kMinTextViewHeight
-        self.allowCaptions = allowCaptions
 
         super.init(frame: CGRect.zero)
 
@@ -607,8 +617,8 @@ class CaptioningToolbar: UIView, UITextViewDelegate {
         textView.addBorder(with: UIColor.lightGray)
         textView.font = UIFont.ows_dynamicTypeBody()
         textView.returnKeyType = .done
-        if !allowCaptions {
-            textView.isHidden = true
+        if let defaultCaption = defaultCaption {
+            textView.text = defaultCaption
         }
 
         let sendTitle = NSLocalizedString("ATTACHMENT_APPROVAL_SEND_BUTTON", comment: "Label for 'send' button in the 'attachment approval' dialog.")

SignalMessaging/attachments/MediaMessageView.swift

@@ -112,6 +112,8 @@ public class MediaMessageView: UIView, OWSAudioAttachmentPlayerDelegate {
             createAudioPreview()
         } else if attachment.isOversizeText {
             createTextPreview()
+        } else if attachment.isUrl {
+            createUrlPreview()
         } else {
             createGenericPreview()
         }
@@ -306,7 +308,7 @@ public class MediaMessageView: UIView, OWSAudioAttachmentPlayerDelegate {
 
         let messageTextView = UITextView()
         messageTextView.font = UIFont.ows_dynamicTypeBody()
-                messageTextView.backgroundColor = UIColor.clear
+        messageTextView.backgroundColor = UIColor.clear
         messageTextView.isOpaque = false
         messageTextView.isEditable = false
         messageTextView.isSelectable = false
@@ -320,7 +322,7 @@ public class MediaMessageView: UIView, OWSAudioAttachmentPlayerDelegate {
         messageTextView.linkTextAttributes = [NSForegroundColorAttributeName : textColor,
                                               NSUnderlineStyleAttributeName : [NSUnderlineStyle.styleSingle,
                                                                                NSUnderlineStyle.patternSolid]
-                                              ]
+        ]
         messageTextView.dataDetectorTypes = [.link, .address, .calendarEvent]
         messageTextView.text = messageText
 
@@ -340,6 +342,18 @@ public class MediaMessageView: UIView, OWSAudioAttachmentPlayerDelegate {
         messageTextView.autoPinTrailingToSuperview(withMargin:15)
     }
 
+    private func createUrlPreview() {
+
+        let data = attachment.data
+        guard let messageText = String(data: data, encoding: String.Encoding.utf8) else {
+            createGenericPreview()
+            return
+        }
+
+        // Show nothing; URLs should only appear in the attachment approval view
+        // of the SAE and in this context the URL will be placed in the caption field.
+    }
+
     private func createGenericPreview() {
         var subviews = [UIView]()
 

SignalMessaging/attachments/SignalAttachment.swift

@@ -419,6 +419,11 @@ public class SignalAttachment: NSObject {
         return dataUTI == kOversizeTextAttachmentUTI
     }
 
+    @objc
+    public var isUrl: Bool {
+        return dataUTI == (kUTTypeURL as String)
+    }
+
     @objc
     public class func pasteboardHasPossibleAttachment() -> Bool {
         return UIPasteboard.general.numberOfItems > 0

SignalShareExtension/ShareViewController.swift

@@ -605,9 +605,7 @@ public class ShareViewController: UINavigationController, ShareViewDelegate, SAE
             // start with base utiType, but it might be something generic like "image"
             var specificUTIType = utiType
             if utiType == (kUTTypeURL as String) {
-                // Share URLs as oversize text messages whose text content is the URL.
-                Logger.debug("\(self.logTag) using text UTI type for URL.")
-                specificUTIType = kOversizeTextAttachmentUTI as String
+                // Use kUTTypeURL for URLs.
             } else if url.pathExtension.count > 0 {
                 // Determine a more specific utiType based on file extension
                 if let typeExtension = MIMETypeUtil.utiType(forFileExtension: url.pathExtension) {