"Done" button for caption toolbar

// FREEBIE

SignalMessaging/attachments/AttachmentApprovalViewController.swift

@@ -405,27 +405,7 @@ class CaptioningToolbar: UIView, UITextViewDelegate {
         self.captioningToolbarDelegate?.captioningToolbarDidTapSend(self, captionText: self.textView.text)
     }
 
-    // MARK: - UITextViewDelegate
-
-    public func textViewDidChange(_ textView: UITextView) {
-        Logger.debug("\(self.logTag) in \(#function)")
-
-        // compute new height assuming width is unchanged
-        let currentSize = textView.frame.size
-        let newHeight = clampedTextViewHeight(fixedWidth: currentSize.width)
-
-        if newHeight != self.textViewHeight {
-            Logger.debug("\(self.logTag) TextView height changed: \(self.textViewHeight) -> \(newHeight)")
-            self.textViewHeight = newHeight
-            self.setNeedsLayout()
-            self.layoutIfNeeded()
-        }
-    }
-
-    private func clampedTextViewHeight(fixedWidth: CGFloat) -> CGFloat {
-        let contentSize = textView.sizeThatFits(CGSize(width: fixedWidth, height: CGFloat.greatestFiniteMagnitude))
-        return Clamp(contentSize.height, kMinTextViewHeight, maxTextViewHeight)
-    }
+    // MARK: - UIView Overrides
 
     // We do progammatic layout, explicitly computing and setting frames since autoLayout does
     // not seem to work with inputAccessory views, even when forcing a layout.
@@ -463,4 +443,40 @@ class CaptioningToolbar: UIView, UITextViewDelegate {
 
         Logger.debug("After layout >>> self: \(self.frame) textView: \(self.textView.frame), sendButton:\(sendButton.frame)")
     }
+
+    // MARK: - UITextViewDelegate
+
+    public func textViewDidChange(_ textView: UITextView) {
+        Logger.debug("\(self.logTag) in \(#function)")
+
+        // compute new height assuming width is unchanged
+        let currentSize = textView.frame.size
+        let newHeight = clampedTextViewHeight(fixedWidth: currentSize.width)
+
+        if newHeight != self.textViewHeight {
+            Logger.debug("\(self.logTag) TextView height changed: \(self.textViewHeight) -> \(newHeight)")
+            self.textViewHeight = newHeight
+            self.setNeedsLayout()
+            self.layoutIfNeeded()
+        }
+    }
+
+    public func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
+        // Though we can wrap the text, we don't want to encourage multline captions, plus a "done" button
+        // allows the user to get the keyboard out of the way while in the attachment approval view.
+        if text == "\n" {
+            textView.resignFirstResponder()
+            return false
+        } else {
+            return true
+        }
+    }
+
+    // MARK: - Helpers
+
+    private func clampedTextViewHeight(fixedWidth: CGFloat) -> CGFloat {
+        let contentSize = textView.sizeThatFits(CGSize(width: fixedWidth, height: CGFloat.greatestFiniteMagnitude))
+        return Clamp(contentSize.height, kMinTextViewHeight, maxTextViewHeight)
+    }
+
 }