userUpdateTextEditingValue method Null safety

  1. @override
void userUpdateTextEditingValue(
  1. TextEditingValue value,
  2. SelectionChangedCause? cause

Indicates that the user has requested the delegate to replace its current text editing state with value.

The new value is treated as user input and thus may subject to input formatting.

See also:


void userUpdateTextEditingValue(TextEditingValue value, SelectionChangedCause? cause) {
  // Compare the current TextEditingValue with the pre-format new
  // TextEditingValue value, in case the formatter would reject the change.
  final bool shouldShowCaret = widget.readOnly
    ? _value.selection != value.selection
    : _value != value;
  if (shouldShowCaret) {
    _scheduleShowCaretOnScreen(withAnimation: true);

  // Even if the value doesn't change, it may be necessary to focus and build
  // the selection overlay. For example, this happens when right clicking an
  // unfocused field that previously had a selection in the same spot.
  if (value == textEditingValue) {
    if (!widget.focusNode.hasFocus) {

  _formatAndSetValue(value, cause, userInteraction: true);