enable multiline textfield to show more lines and limit to 1000 characters maximum input.

Antidote/ChatInputView.swift

@@ -11,6 +11,10 @@ private struct Constants {
     static let CameraHorizontalOffset: CGFloat = 10.0
     static let CameraBottomOffset: CGFloat = -10.0
     static let TextViewMinHeight: CGFloat = 35.0
+    static let MIN_MYHEIGHT: CGFloat = 45
+    static let MAX_MYHEIGHT: CGFloat = 90
+    static let MARGIN_MYHEIGHT: CGFloat = 5
+    static let MAX_TEXT_INPUT_CHARS = 1000
 }
 
 protocol ChatInputViewDelegate: class {
@@ -48,6 +52,8 @@ class ChatInputView: UIView {
     fileprivate var cameraButton: UIButton!
     fileprivate var textView: UITextView!
     fileprivate var sendButton: UIButton!
+    fileprivate var myHeight: Constraint!
+    fileprivate var didconstraint = 0
 
     init(theme: Theme) {
         self.maxHeight = 0.0
@@ -82,17 +88,38 @@ extension ChatInputView {
 
     @objc func sendButtonPressed() {
         delegate?.chatInputViewSendButtonPressed(self)
+        updateTextviewHeight(textView)
     }
 }
 
 extension ChatInputView: UITextViewDelegate {
     func textViewDidChange(_ textView: UITextView) {
         updateViews()
+        updateTextviewHeight(textView)
         delegate?.chatInputViewTextDidChange(self)
     }
+
+    override func didMoveToWindow() {
+        updateTextviewHeight(textView)
+    }
+
+    func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
+        // get the current text, or use an empty string if that failed
+        let currentText = textView.text ?? ""
+
+        // attempt to read the range they are trying to change, or exit if we can't
+        guard let stringRange = Range(range, in: currentText) else { return false }
+
+        // add their new text to the existing text
+        let updatedText = currentText.replacingCharacters(in: stringRange, with: text)
+
+        // make sure the result is under MAX_TEXT_INPUT_CHARS characters
+        return updatedText.count <= Constants.MAX_TEXT_INPUT_CHARS
+    }
 }
 
 private extension ChatInputView {
+
     func createViews(_ theme: Theme) {
         topBorder = UIView()
         topBorder.backgroundColor = theme.colorForType(.SeparatorsAndBorders)
@@ -116,6 +143,8 @@ private extension ChatInputView {
         textView.layer.borderColor = theme.colorForType(.SeparatorsAndBorders).cgColor
         textView.layer.masksToBounds = true
         textView.setContentHuggingPriority(UILayoutPriority(rawValue: 0.0), for: .horizontal)
+        textView.autocapitalizationType = .none
+
         addSubview(textView)
 
         sendButton = UIButton(type: .system)
@@ -151,16 +180,37 @@ private extension ChatInputView {
         }
     }
 
-    func updateViews() {
-        let size = textView.sizeThatFits(CGSize(width: textView.frame.size.width, height: CGFloat.greatestFiniteMagnitude))
+    func updateTextviewHeight(_ t : UITextView)
+    {
+        if (self.didconstraint == 1)
+        {
+            self.myHeight.uninstall()
+            self.didconstraint = 0
+        }
 
-        if maxHeight > 0.0 {
-            textView.isScrollEnabled = (size.height + 2 * Constants.Offset) > maxHeight
+        let text_needs_size  = t.sizeThatFits(
+            CGSize(width: t.frame.size.width,
+                   height: CGFloat.greatestFiniteMagnitude))
+        var new_height = text_needs_size.height + Constants.MARGIN_MYHEIGHT
+        if (text_needs_size.height > Constants.MAX_MYHEIGHT)
+        {
+            new_height = Constants.MAX_MYHEIGHT
         }
-        else {
-            textView.isScrollEnabled = false
+        else if (text_needs_size.height < Constants.MIN_MYHEIGHT) {
+            new_height = Constants.MIN_MYHEIGHT
         }
 
+        if (self.didconstraint == 0) {
+            self.didconstraint = 1
+            self.snp.makeConstraints {
+                self.myHeight = $0.height.equalTo(new_height).constraint
+            }
+        }
+    }
+
+    func updateViews() {
+        textView.isScrollEnabled = true
+        textView.autocapitalizationType = .none
         cameraButton.isEnabled = cameraButtonEnabled
         sendButton.isEnabled = !textView.text.isEmpty
     }