ok i decided to use ScrollablePositionedList.builder https://pub.dev/packages/scrollable_positioned_list

instead of ListView.builderfor more controlling of the index navigation ..

we know that ScrollablePositionedList.builder use ItemScrollController() instead of ScrollController()

using ScrollController() we can do the following to detect if we reach the top list or bottom

ScrollController scrollController= ScrollController(); 

     scrollController.addListener(() {
          if(scrollController.position.atEdge){
            if (scrollController.position.pixels == 0) {
              ///we arrive to the end        
              }
            }else{
             ///we arrive to the top
            }
          }
        });

but how could i do the same with using ScrollablePositionedList.builder that use ItemScrollController()

so i tried to do this

    ItemScrollController scrollController = ItemScrollController(); 
  final listener = ItemPositionsListener.create();
    
       listener.itemPositions.addListener(() {
          listener.itemPositions.value // here all what i get .. i cannot see any 
         position.atEdge or pixels like normal ScrollController
        });

really does it not support the detection of top list or bottom or something went wrong with me ? thanks

CodePudding user response：

You can check

• if the value of itemPositionsListener.itemPositions.value.first.index is 0

to say it is on top. And to check

• if the value of ${itemPositionsListener.itemPositions.value.last.index} = list.length - 1

to say it reaches the bottom.

    itemPositionsListener.itemPositions.addListener(() {
      print(
          '====current first ${itemPositionsListener.itemPositions.value.first.index}====');
      print(
          '====current last ${itemPositionsListener.itemPositions.value.last.index}====');
    });