[ticket_fold] FlatButton onTap inside ticket_fold doesn't trigger

[ricardogobbo]

Steps to reproduce:

1. Remove barcode image from flight_barcode.dart and add a FlatButton like follows:

FlatButton(
  child: Text("Button"),
  onPressed: () => print("button works"),
)

The onTap function doesnt trigger. The card keeps folding.

[masterashu]

This happens because the FlightBarcode is Wrapped inside a Gesture detector here.

[masterashu]

You can refer here to find how to that behavior.

[ricardogobbo]

That's an unexpected behavior.

Look at this Widget. When I tap on red container, onTap is fired. When I press the button, onPressed is triggered.

class MyHomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("GestureDetector Test")),
      body: Column(
        children: <Widget>[
          GestureDetector(
            onTap: () => print("gestureDetector onTap"),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.stretch,
              children: <Widget>[
                Container(
                  color: Colors.red, 
                  height: 200, 
                  child: Text("Gesture"),
                ),
                FlatButton(
                  child: Text("button"), 
                  onPressed: () => print("button onPressed"),
                )
              ],
            ),
          )
        ],
      ),
    );
  }
}

[masterashu]

In the Flutter documentation here it is mentioned that in Gesture Arena only one of the Gesture is declared as victorious. This might differ from one case to another case. Hence it requires custom GestureDetectors.

[ricardogobbo]

Gesture arena didn't recognize button onPressed gesture.

Gesture arena 48   ❙ ★ Opening new gesture arena.
// GestureDetector's onTap 
Gesture arena 48   ❙ Adding: TapGestureRecognizer#6cdd6(debugOwner: GestureDetector, state: ready, button: 1)
// ListView scroll
Gesture arena 48   ❙ Adding: VerticalDragGestureRecognizer#675e5(start behavior: start)
Gesture arena 48   ❙ Closing with 2 members.
Gesture arena 48   ❙ Rejecting: VerticalDragGestureRecognizer#675e5(start behavior: start)
Gesture arena 48   ❙ Sweeping with 1 member.
Gesture arena 48   ❙ Winner: TapGestureRecognizer#6cdd6(debugOwner: GestureDetector, state: ready, finalPosition: Offset(129.4, 493.4), finalLocalPosition: Offset(129.4, 380.3), button: 1, sent tap down)

[esDotDev]

We've refactored the example to allow for embedded buttons :)