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Flutter – The argument type 'String' can't be assigned to the parameter type

I’m learning Flutter.

Have this model class:

class TaskModel {
  String task;

  TaskModel({required this.task});
}

class TaskProvider extends ChangeNotifier {
  List<TaskModel> taskList = [];

  void addNotes(TaskModel userInput) {
    return taskList.add(userInput);
  }
}

When I press the button, the input in the text field should be added to taskList:

TextEditingController _controller = TextEditingController();
onPressed: () {
  context.read<TaskProvider>().addNotes(_controller.text);}

I get this error:

Error in ‘_controller.text’ The argument type ‘String’ can’t be assigned to the parameter type ‘TaskModel’

I need to find a way to convert to match that type

Tags:

3

Answers


  1. 0

    change the add Task like this

    class TaskProvider extends ChangeNotifier {
  List<TaskModel> taskList = [];

  void addNotes(String userInput) {
    return taskList.add(TaskModel(task: userInput);
  }
}

    Explanation:
    The error arises because you’re trying to pass a String (the text from the text field) to the addNotes function which expects a TaskModel object.

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  2. 0

    your addNotes method expects a TaskModel object, but you are trying to add a string to your taskList

    class TaskModel {
          String task;
        
          TaskModel({required this.task});
        }
        
        
        class TaskProvider extends ChangeNotifier {
          List<TaskModel> taskList = [];
        
          void addNotes(TaskModel userInput) {
            return taskList.add(userInput);
           notifyListeners();
        
 }
}


TextEditingController _controller = TextEditingController();
TextFormField(controller: _controller)



     onPressed:(){
    //validation - optional
        TaskModel taskModelObject = TaskModel(task:_controller.text);
        context.read<TaskProvider>().addNotes(taskModelObject);
        _controller.clear();
}
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  3. 0

    The data that needs to be added is TaskModel not a string, you should do this:

    addNotes(TaskModel(task:_controller.text))

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