Add enableSuggestions flag to TextField and TextFormField (#42550)

This flag controls Android's keyboard suggestions on/off

packages/flutter/lib/src/cupertino/text_field.dart

@@ -197,8 +197,8 @@ class CupertinoTextField extends StatefulWidget {
   ///
   /// The [autocorrect], [autofocus], [clearButtonMode], [dragStartBehavior],
   /// [expands], [maxLengthEnforced], [obscureText], [prefixMode], [readOnly],
-  /// [scrollPadding], [suffixMode], and [textAlign] properties must not be
-  /// null.
+  /// [scrollPadding], [suffixMode], [textAlign], and [enableSuggestions] properties
+  /// must not be null.
   ///
   /// See also:
   ///
@@ -235,6 +235,7 @@ class CupertinoTextField extends StatefulWidget {
     this.autofocus = false,
     this.obscureText = false,
     this.autocorrect = true,
+    this.enableSuggestions = true,
     this.maxLines = 1,
     this.minLines,
     this.expands = false,
@@ -260,6 +261,7 @@ class CupertinoTextField extends StatefulWidget {
        assert(autofocus != null),
        assert(obscureText != null),
        assert(autocorrect != null),
+       assert(enableSuggestions != null),
        assert(maxLengthEnforced != null),
        assert(scrollPadding != null),
        assert(dragStartBehavior != null),
@@ -415,6 +417,9 @@ class CupertinoTextField extends StatefulWidget {
   /// {@macro flutter.widgets.editableText.autocorrect}
   final bool autocorrect;
 
+  /// {@macro flutter.services.textInput.enableSuggestions}
+  final bool enableSuggestions;
+
   /// {@macro flutter.widgets.editableText.maxLines}
   final int maxLines;
 
@@ -561,7 +566,8 @@ class CupertinoTextField extends StatefulWidget {
     properties.add(DiagnosticsProperty<TextStyle>('style', style, defaultValue: null));
     properties.add(DiagnosticsProperty<bool>('autofocus', autofocus, defaultValue: false));
     properties.add(DiagnosticsProperty<bool>('obscureText', obscureText, defaultValue: false));
-    properties.add(DiagnosticsProperty<bool>('autocorrect', autocorrect, defaultValue: false));
+    properties.add(DiagnosticsProperty<bool>('autocorrect', autocorrect, defaultValue: true));
+    properties.add(DiagnosticsProperty<bool>('enableSuggestions', enableSuggestions, defaultValue: true));
     properties.add(IntProperty('maxLines', maxLines, defaultValue: 1));
     properties.add(IntProperty('minLines', minLines, defaultValue: null));
     properties.add(DiagnosticsProperty<bool>('expands', expands, defaultValue: false));
@@ -877,6 +883,7 @@ class _CupertinoTextFieldState extends State<CupertinoTextField> with AutomaticK
           autofocus: widget.autofocus,
           obscureText: widget.obscureText,
           autocorrect: widget.autocorrect,
+          enableSuggestions: widget.enableSuggestions,
           maxLines: widget.maxLines,
           minLines: widget.minLines,
           expands: widget.expands,

packages/flutter/lib/src/material/text_field.dart

@@ -277,8 +277,8 @@ class TextField extends StatefulWidget {
   /// is null (the default) and [readOnly] is true.
   ///
   /// The [textAlign], [autofocus], [obscureText], [readOnly], [autocorrect],
-  /// [maxLengthEnforced], [scrollPadding], [maxLines], and [maxLength]
-  /// arguments must not be null.
+  /// [maxLengthEnforced], [scrollPadding], [maxLines], [maxLength], and
+  /// [enableSuggestions] arguments must not be null.
   ///
   /// See also:
   ///
@@ -303,6 +303,7 @@ class TextField extends StatefulWidget {
     this.autofocus = false,
     this.obscureText = false,
     this.autocorrect = true,
+    this.enableSuggestions = true,
     this.maxLines = 1,
     this.minLines,
     this.expands = false,
@@ -329,6 +330,7 @@ class TextField extends StatefulWidget {
        assert(autofocus != null),
        assert(obscureText != null),
        assert(autocorrect != null),
+       assert(enableSuggestions != null),
        assert(enableInteractiveSelection != null),
        assert(maxLengthEnforced != null),
        assert(scrollPadding != null),
@@ -454,6 +456,9 @@ class TextField extends StatefulWidget {
   /// {@macro flutter.widgets.editableText.autocorrect}
   final bool autocorrect;
 
+  /// {@macro flutter.services.textInput.enableSuggestions}
+  final bool enableSuggestions;
+
   /// {@macro flutter.widgets.editableText.maxLines}
   final int maxLines;
 
@@ -676,6 +681,7 @@ class TextField extends StatefulWidget {
     properties.add(DiagnosticsProperty<bool>('autofocus', autofocus, defaultValue: false));
     properties.add(DiagnosticsProperty<bool>('obscureText', obscureText, defaultValue: false));
     properties.add(DiagnosticsProperty<bool>('autocorrect', autocorrect, defaultValue: true));
+    properties.add(DiagnosticsProperty<bool>('enableSuggestions', enableSuggestions, defaultValue: true));
     properties.add(IntProperty('maxLines', maxLines, defaultValue: 1));
     properties.add(IntProperty('minLines', minLines, defaultValue: null));
     properties.add(DiagnosticsProperty<bool>('expands', expands, defaultValue: false));
@@ -955,6 +961,7 @@ class _TextFieldState extends State<TextField> implements TextSelectionGestureDe
         autofocus: widget.autofocus,
         obscureText: widget.obscureText,
         autocorrect: widget.autocorrect,
+        enableSuggestions: widget.enableSuggestions,
         maxLines: widget.maxLines,
         minLines: widget.minLines,
         expands: widget.expands,

packages/flutter/lib/src/material/text_form_field.dart

@@ -98,6 +98,7 @@ class TextFormField extends FormField<String> {
     bool showCursor,
     bool obscureText = false,
     bool autocorrect = true,
+    bool enableSuggestions = true,
     bool autovalidate = false,
     bool maxLengthEnforced = true,
     int maxLines = 1,
@@ -125,6 +126,7 @@ class TextFormField extends FormField<String> {
        assert(readOnly != null),
        assert(obscureText != null),
        assert(autocorrect != null),
+       assert(enableSuggestions != null),
        assert(autovalidate != null),
        assert(maxLengthEnforced != null),
        assert(scrollPadding != null),
@@ -177,6 +179,7 @@ class TextFormField extends FormField<String> {
         showCursor: showCursor,
         obscureText: obscureText,
         autocorrect: autocorrect,
+        enableSuggestions: enableSuggestions,
         maxLengthEnforced: maxLengthEnforced,
         maxLines: maxLines,
         minLines: minLines,

packages/flutter/lib/src/services/text_input.dart

@@ -386,6 +386,7 @@ class TextInputConfiguration {
     this.inputType = TextInputType.text,
     this.obscureText = false,
     this.autocorrect = true,
+    this.enableSuggestions = true,
     this.actionLabel,
     this.inputAction = TextInputAction.done,
     this.keyboardAppearance = Brightness.light,
@@ -393,6 +394,7 @@ class TextInputConfiguration {
   }) : assert(inputType != null),
        assert(obscureText != null),
        assert(autocorrect != null),
+       assert(enableSuggestions != null),
        assert(keyboardAppearance != null),
        assert(inputAction != null),
        assert(textCapitalization != null);
@@ -410,6 +412,20 @@ class TextInputConfiguration {
   /// Defaults to true.
   final bool autocorrect;
 
+  /// {@template flutter.services.textInput.enableSuggestions}
+  /// Whether to show input suggestions as the user types.
+  ///
+  /// This flag only affects Android. On iOS, suggestions are tied directly to
+  /// [autocorrect], so that suggestions are only shown when [autocorrect] is
+  /// true. On Android autocorrection and suggestion are controlled separately.
+  ///
+  /// Defaults to true. Cannot be null.
+  ///
+  /// See also:
+  ///  * <https://developer.android.com/reference/android/text/InputType.html#TYPE_TEXT_FLAG_NO_SUGGESTIONS>
+  /// {@endtemplate}
+  final bool enableSuggestions;
+
   /// What text to display in the text input control's action button.
   final String actionLabel;
 
@@ -439,6 +455,7 @@ class TextInputConfiguration {
       'inputType': inputType.toJson(),
       'obscureText': obscureText,
       'autocorrect': autocorrect,
+      'enableSuggestions': enableSuggestions,
       'actionLabel': actionLabel,
       'inputAction': inputAction.toString(),
       'textCapitalization': textCapitalization.toString(),

packages/flutter/lib/src/widgets/editable_text.dart

@@ -342,9 +342,9 @@ class EditableText extends StatefulWidget {
   /// The [controller], [focusNode], [obscureText], [autocorrect], [autofocus],
   /// [showSelectionHandles], [enableInteractiveSelection], [forceLine],
   /// [style], [cursorColor], [cursorOpacityAnimates],[backgroundCursorColor],
-  /// [paintCursorAboveText], [textAlign], [dragStartBehavior], [scrollPadding],
-  /// [dragStartBehavior], [toolbarOptions], [rendererIgnoresPointer], and
-  /// [readOnly] arguments must not be null.
+  /// [enableSuggestions], [paintCursorAboveText], [textAlign], [dragStartBehavior],
+  /// [scrollPadding], [dragStartBehavior], [toolbarOptions],
+  /// [rendererIgnoresPointer], and [readOnly] arguments must not be null.
   EditableText({
     Key key,
     @required this.controller,
@@ -352,6 +352,7 @@ class EditableText extends StatefulWidget {
     this.readOnly = false,
     this.obscureText = false,
     this.autocorrect = true,
+    this.enableSuggestions = true,
     @required this.style,
     StrutStyle strutStyle,
     @required this.cursorColor,
@@ -401,6 +402,7 @@ class EditableText extends StatefulWidget {
        assert(focusNode != null),
        assert(obscureText != null),
        assert(autocorrect != null),
+       assert(enableSuggestions != null),
        assert(showSelectionHandles != null),
        assert(enableInteractiveSelection != null),
        assert(readOnly != null),
@@ -515,6 +517,9 @@ class EditableText extends StatefulWidget {
   /// {@endtemplate}
   final bool autocorrect;
 
+  /// {@macro flutter.services.textInput.enableSuggestions}
+  final bool enableSuggestions;
+
   /// The text style to use for the editable text.
   final TextStyle style;
 
@@ -1037,6 +1042,7 @@ class EditableText extends StatefulWidget {
     properties.add(DiagnosticsProperty<FocusNode>('focusNode', focusNode));
     properties.add(DiagnosticsProperty<bool>('obscureText', obscureText, defaultValue: false));
     properties.add(DiagnosticsProperty<bool>('autocorrect', autocorrect, defaultValue: true));
+    properties.add(DiagnosticsProperty<bool>('enableSuggestions', enableSuggestions, defaultValue: true));
     style?.debugFillProperties(properties);
     properties.add(EnumProperty<TextAlign>('textAlign', textAlign, defaultValue: null));
     properties.add(EnumProperty<TextDirection>('textDirection', textDirection, defaultValue: null));
@@ -1394,6 +1400,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
               inputType: widget.keyboardType,
               obscureText: widget.obscureText,
               autocorrect: widget.autocorrect,
+              enableSuggestions: widget.enableSuggestions,
               inputAction: widget.textInputAction ?? (widget.keyboardType == TextInputType.multiline
                   ? TextInputAction.newline
                   : TextInputAction.done
@@ -1842,6 +1849,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
               textWidthBasis: widget.textWidthBasis,
               obscureText: widget.obscureText,
               autocorrect: widget.autocorrect,
+              enableSuggestions: widget.enableSuggestions,
               offset: offset,
               onSelectionChanged: _handleSelectionChanged,
               onCaretChanged: _handleCaretChanged,
@@ -1907,6 +1915,7 @@ class _Editable extends LeafRenderObjectWidget {
     this.locale,
     this.obscureText,
     this.autocorrect,
+    this.enableSuggestions,
     this.offset,
     this.onSelectionChanged,
     this.onCaretChanged,
@@ -1944,6 +1953,7 @@ class _Editable extends LeafRenderObjectWidget {
   final bool obscureText;
   final TextWidthBasis textWidthBasis;
   final bool autocorrect;
+  final bool enableSuggestions;
   final ViewportOffset offset;
   final SelectionChangedHandler onSelectionChanged;
   final CaretChangedHandler onCaretChanged;

packages/flutter/test/widgets/editable_text_test.dart

@@ -119,6 +119,7 @@ void main() {
     expect(editableText.maxLines, equals(1));
     expect(editableText.obscureText, isFalse);
     expect(editableText.autocorrect, isTrue);
+    expect(editableText.enableSuggestions, isTrue);
     expect(editableText.textAlign, TextAlign.start);
     expect(editableText.cursorWidth, 2.0);
   });
@@ -327,6 +328,36 @@ void main() {
         equals('TextInputAction.done'));
   });
 
+  testWidgets('enableSuggestions flag is sent to the engine properly', (WidgetTester tester) async {
+    final TextEditingController controller = TextEditingController();
+    const bool enableSuggestions = false;
+    await tester.pumpWidget(
+      MediaQuery(
+        data: const MediaQueryData(devicePixelRatio: 1.0),
+        child: Directionality(
+          textDirection: TextDirection.ltr,
+          child: FocusScope(
+            node: focusScopeNode,
+            autofocus: true,
+            child: EditableText(
+              controller: controller,
+              backgroundCursorColor: Colors.grey,
+              focusNode: focusNode,
+              enableSuggestions: enableSuggestions,
+              style: textStyle,
+              cursorColor: cursorColor,
+            ),
+          ),
+        ),
+      ),
+    );
+
+    await tester.tap(find.byType(EditableText));
+    await tester.showKeyboard(find.byType(EditableText));
+    await tester.idle();
+    expect(tester.testTextInput.setClientArgs['enableSuggestions'], enableSuggestions);
+  });
+
   testWidgets('selection overlay will update when text grow bigger', (WidgetTester tester) async {
     final TextEditingController controller = TextEditingController.fromValue(
         const TextEditingValue(