Flutter TextFormField with non-const decoration-CodePudding

I want to write something like a function that generates TextFormFields with different names, but I don't want the labelText attribute to be const. That way I can easily rubber stamp out a bunch of similar fields that have different names.

For example

TextFormField myFormField(myMapType myMap, String fieldName) {
    return TextFormField(
        decoration: const InputDecoration(
          border: OutlineInputBorder(),
          labelText: fieldName,
        ),
        validator: (value) {
          if (value == null || value.isEmpty) {
            return 'Please enter your $fieldName';
          }
          return null;
        },
        initialValue: myMap.attribute[fieldName],
        onSaved: (val) {
          setState(
            () {
              myMap.setAttribute(fieldName, val!);
            },
          );
        });
  }

But that gives an error "Invalid constant value" at the line "labelText: fieldName". What's the trick needed to accomplish what I'm trying to do? Or what dumb mistake did I make?

CodePudding user response：

fieldName will get on runtime rather than compile time. Therefore you cant use const

You can do

return TextFormField(
    decoration: InputDecoration(
      border: const OutlineInputBorder(), //this can be const
      labelText: fieldName,
    ),
    validator: (value) {

You can check What is the difference between the "const" and "final" keywords in Dart?