Why is my GestureDetector onTap event not firing? - flutter

Question

I've created a custom form field and in it is a GestureDetector but the onTap is not firing. I want to use the GestureDetector to collect the click event when someone clicks on the form field in a disabled state so I can launch a dialog box. Code is below. I'm wondering what I must be doing wrong or misunderstanding.
Widget _customFormField(
{required String title,
required String initialValue,
required int maxLines,
required int maxLength,
required bool enabled,
required TextEditingController controller,
bool autoFocus = false,
required FocusNode currentFocusNode,
required FocusNode futureFocusNode,
Function? function,
bool formEnd = false}) {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(title,
style: const TextStyle(
fontSize: 14.0,
fontWeight: FontWeight.bold,
fontFamily: 'Ariel',
color: Colors.pink)),
GestureDetector(
onTap: () {
print('onTap'); // <-------------------- This never gets hit
function;
},
child: TextFormField(
autofocus: autoFocus,
enabled: enabled,
textInputAction:
formEnd ? TextInputAction.done : TextInputAction.next,
onEditingComplete: () =>
FocusScope.of(context).requestFocus(futureFocusNode),
focusNode: currentFocusNode,
controller: controller,
keyboardType: TextInputType.text,
validator: (value) {
if (value!.isEmpty) {
if (_formValid) {
_formValid = false;
currentFocusNode.requestFocus();
}
//title.toLowerCase()
return 'Please enter the ${title.toLowerCase()}';
} else {
return null;
}
},
),
),
],
);
}
I've tried changing it to an InkWell but it behaves the same.
I've removed some styling code from the example but nothing that could have an affect on the problem.

Answer 1

well the function property that you got from the properties are the definition of the method, when you do :
onTap: () {
print('onTap');
function;
},
you not calling the method, you putting it there, you need to call it so it runs, by adding () or by calling call() on it.
onTap: () {
print('onTap');
function(); // like this
// function.call(); or like this
},

Answer 2

Try the following:
onTap: () {
print('onTap'); // <-------------------- This never gets hit
if (function != null) function.call();
}