TabBarView 滑动事件监听器

Question

I'm trying to setState() whenever a TabBarView will change its index on swipe.

TabBarView(
  controller: _tabController,
  children: [
    fooScreen(),
    barScreen(),
  ]

So far I've been able to use _tabController.addListener() but this only triggers whenever the TabBarView index has already changed. Is there any way to get it to trigger when the index is going to change?

Answer 1

Since you need your event to get triggered on swipe then you could wrap the widget you are interested in listening for the swipe gesture .

In code this could be achieved using the GestureDetector (which I'm sure you've used already).

GestureDetector(
 child: yourWidget,

 onPanUpdate: (d) {
  if (d.delta.dx > 0) {
    //triggered when swiped yourWidget in right direction
  }
});