I'm trying to pass a function as a parameter. My code runs but the function doesn't fire.

I have a Holiday class

  final VoidCallback callback;
  Holiday(this.holidayStart, this.holidayEnd, this.holidayDuration, this.callback);

Inside the Holiday class I have a function to build a widget with a button. here I use...

   onPressed: () {
       callback;
   },

In my main.dart file when I create a new instance of Holiday I pass a function like this....

holidays.add(Holiday(startSelected, endSelected, stay, () { print('pressed'); }))

Everything compiles fine but pressed is never printed. Any ideas what I'm doing wrong here?

Thanks in advance.

CodePudding user response：

In your case, you passed function that does nothing because you put callback but don't call it (via () at the end or .call()). You should write onPressed: callback, or onPressed: () { callback(); },