Question 229775 in Flutter Question posted in
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Flutter – The argument type 'void Function()' can't be assigned to the parameter type 'void Function(LongPressEndDetails)?'

I am trying to set up button, which has green color, when on long press and red, when it is released (back to initial state)

onLong press is working fine, but when I added onLongPress end I got error:

The argument type ‘void Function()’ can’t be assigned to the parameter type ‘void Function(LongPressEndDetails)?’.

Here is my code snippet:

GestureDetector(
  onLongPress: () => setState(() {}),
  onLongPressEnd: () => setState(() {}),
),
Tags:

2

Answers


  1. 0

    onLongPressEnd provides LongPressEndDetails on callback, you need to add param,

    onLongPressEnd: (details) {
  
},

    or ignore like

    onLongPressEnd: (_) {
  
},
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  2. 0

    As the error message says: The onLongPressEnd callback expects a function that also accepts the event details (LongPressEndDetails).

    So your code should look like:

       ...
   onLongPressEnd: (details) => ...
   ...

    If you are not interested in the event details you can ignore them like this:

       onLongPressEnd: (_) => ...
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