Allow to disable autocompletion, close suggestions with Escape key (akvelon#206) (akvelon#219) (akvelon#226)

Author: alexeyinkin

README.md

@@ -363,7 +363,11 @@ The editor performs no syntax analysis and so cannot tell if a given class reall
 the method the user is typing. This feature is meant to simplify typing but not to be relied on
 when exploring classes and methods.
 
-Autocompletion currently cannot be disabled.
+To disable autocompletion:
+
+```dart
+controller.popupController.enabled = false;
+```
 
 ![Suggestions example](https://raw.githubusercontent.com/akvelon/flutter-code-editor/main/example/images/suggestions_example.gif)
 

lib/src/code_field/code_controller.dart

@@ -281,6 +281,10 @@ class CodeController extends TextEditingController {
         insertSelectedWord();
         return KeyEventResult.handled;
       }
+      if (event.logicalKey == LogicalKeyboardKey.escape) {
+        popupController.hide();
+        return KeyEventResult.handled;
+      }
     }
 
     return KeyEventResult.ignored; // The framework will handle.

lib/src/wip/autocomplete/popup_controller.dart

@@ -5,6 +5,7 @@ class PopupController extends ChangeNotifier {
   late List<String> suggestions;
   int _selectedIndex = 0;
   bool shouldShow = false;
+  bool enabled = true;
 
   final ItemScrollController itemScrollController = ItemScrollController();
   final ItemPositionsListener itemPositionsListener =
@@ -23,6 +24,10 @@ class PopupController extends ChangeNotifier {
   int get selectedIndex => _selectedIndex;
 
   void show(List<String> suggestions) {
+    if (enabled == false) {
+      return;
+    }
+
     this.suggestions = suggestions;
     _selectedIndex = 0;
     shouldShow = true;