Invalid constant value on Textformfield-CodePudding

I try to do show and hide password but it says Invalid constant value on the _togglePasswordView, And _isHidden I wonder what I did wrong If someone know plz help

bool _isHidden = true;

 void _togglePasswordView() {
 setState(() {
  _isHidden = !_isHidden;
  });
}

TextFormField(
          obscureText: _isHidden,
          decoration: const InputDecoration(
            hintText: 'Password',
            suffix: InkWell(
              onTap: _togglePasswordView,
              child: Icon(
                _isHidden ? Icons.visibility : Icons.visibility_off,
              ),
            ),
          ),
        ),

CodePudding user response：

So lets make it clear about const keyword. When you use const keyword - you define a value constant from compile-time. It means - its value must be defined before the program even runs. So you may not but any run-time (created at some time when program is running) variables or conditions into constant constructors. Just remove the constant keyword.

CodePudding user response：

You're using something dynamic (here onTap function), inside a const constructor call

JUST REMOVE const KEYWORD and you'll be fine