DragTarget doesnt call onWillAccept with custom Draggable (Flutter) - flutter

Question

I am trying to make Tags which are draggable text so that I can drag them to one of 2 DragTarget I have (ideally being able to move them between 3 DragTarget). Unfortunately I can't make them interact with the DragTargets as they dont even call onWillAccept(). My draggables are DragabbleTag and extends Draggable and my dragTargets are in a Stateful Widget and should accept them.
import 'package:myApp/components/draggableTag.dart';
import 'package:flutter/material.dart';
class DraggableTagTarget extends StatefulWidget {
final String title;
final int maxTagAmount;
final Color backgroundColor;
final List<DraggableTag> tagsPool;
const DraggableTagTarget(
{Key key,
this.title,
this.backgroundColor,
this.tagsPool,
this.maxTagAmount})
: super(key: key);
#override
_DraggableTagTargetState createState() => _DraggableTagTargetState();
}
class _DraggableTagTargetState extends State<DraggableTagTarget> {
String test = "Test";
#override
Widget build(BuildContext context) {
return DragTarget<DraggableTag>(onAccept: (DraggableTag value) {
setState(() {
widget.tagsPool.add(value);
test = value.label;
});
}, onWillAccept: (DraggableTag data) {
bool result =
widget.tagsPool.length <= widget.maxTagAmount ? true : false;
debugPrint("ONWillAccept: " + data.label + " = " + result.toString());
return result;
}, builder: (context, candidateData, rejectedData) {
return Container(
decoration: new BoxDecoration(
color: widget.backgroundColor,
border: Border.all(
color: Colors.black,
),
),
child: Column(
children: <Widget>[
Text(test),
Text(widget.title),
SizedBox(
height: 60,
child: Wrap(
children: widget.tagsPool,
),
),
],
),
);
});
}
}
Custom DragTarget 'DraggableTagTarget'
import 'package:flutter/material.dart';
class DraggableTag extends Draggable<String> {
final String label;
DraggableTag({Key key, this.label})
: super(
key: key,
data: label,
child: idleTag(label),
feedback: feedbackTag(label),
childWhenDragging: ghostTag(label),
);
static Widget idleTag(String label) {
return Container(
padding: const EdgeInsets.symmetric(horizontal: 8.0, vertical: 2.0),
child: Text(
label,
style: TextStyle(
fontSize: 16,
),
),
decoration: BoxDecoration(
color: Colors.blue,
border: Border.all(
color: Colors.black,
),
borderRadius: BorderRadius.all(Radius.circular(20)),
),
);
}
Custom Draggable 'DraggableTag'
I excluded feedbackTag() and ghostTag which shouldnt be relevant
At first my draggableTag was extending a widget but seeing some similar problem I made it into extending directly a Draggable but it didnt help
EDIT:
I am assigning ma values to draggable in a custom DialogWidget (stateful widget) in a list
class _RatingDialogState extends State<RatingDialog> {
List<DraggableTag> tagsPool = [
DraggableTag(label: "Acting"),
DraggableTag(label: "Scenario"),
DraggableTag(label: "Pace"),
DraggableTag(label: "Length"),
DraggableTag(label: "Message"),
];
List<DraggableTag> negativeTagsPool = [];
List<DraggableTag> positiveTagsPool = [];
#override
Widget build(BuildContext context) {
return Dialog(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10),
),
elevation: 0,
backgroundColor: Colors.transparent,
child: contentBox(context),
);
}
contentBox(context) {
return Stack(
...
Wrap(
children: tagsPool,
),
SizedBox(height: 22),
Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: <Widget>[
Flexible(
child: FractionallySizedBox(
widthFactor: 0.85,
child: DraggableTagTarget(
title: "Negative",
backgroundColor: Colors.red,
tagsPool: negativeTagsPool,
maxTagAmount: 3),
),
),
Flexible(
child: FractionallySizedBox(
widthFactor: 0.85,
child: DraggableTagTarget(
title: "Positive",
backgroundColor: Colors.green,
tagsPool: positiveTagsPool,
maxTagAmount: 3),
),
),
]),
...
SOLUTION: as ikerfah explained, I didnt put the right type into <> because I was confused to what my DraggableTag class was. I made another class to contains the data Tag so that both my DragTarget and DraggableTag use this class

Answer 1

Draggable and DragTarget must have the same generic type, but you have Draggable<String> and DragTarget<DraggableTag>