AlwaysAtTheEndTextInputFormatter class

AlwaysAtTheEndTextInputFormatter is a TextInputFormatter that forces the cursor to always stay at the end of what is being typed.

Note, just adding AlwaysAtTheEndTextInputFormatter does not prevent text selections, and does not prevent the user to move the cursor using the keyboard arrows. However, if the user types a character when not at the end, the text remains unchanged and the cursor goes to the end of the text.

You can improve this by adding two more changes to your code:

  1. Add enableInteractiveSelection: false to the TextField, which will prevent long press selection, copy/paste menu, and selection handles.

  2. Create a controller and add the following code to your widget's initState(), which will prevent the cursor from moving horizontally with the keyboard arrows:

final controller = TextEditingController();

bool _fixingSelection = false;

@override
void initState() {
  super.initState();

  controller.addListener(() {
    if (_fixingSelection) return;

    final textLength = controller.text.length;
    final selection = controller.selection;

    if (!selection.isCollapsed || selection.baseOffset != textLength) {
      _fixingSelection = true;
      controller.selection = TextSelection.collapsed(offset: textLength);
      _fixingSelection = false;
    }
  });
}

Then:

TextField(
  controller: controller,
  enableInteractiveSelection: false,
  inputFormatters: [
    AlwaysAtTheEndTextInputFormatter.instance,
  ],
)
Inheritance

Properties

hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

formatEditUpdate(TextEditingValue oldValue, TextEditingValue newValue) → TextEditingValue
Called when text is being typed or cut/copy/pasted in the EditableText.
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited

Static Properties

instance → AlwaysAtTheEndTextInputFormatter
final