How to use Gap in ListView's children?

mono0926 commented 4 years ago

Neither Gap nor SliverGap not seems works with ListView 🤔

ListView x Gap

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ListView(
        children: const [
          Gap.expand(100, color: Colors.red),
        ],
      ),
    );
  }

I/flutter (12403): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter (12403): The following assertion was thrown during performLayout():
I/flutter (12403): A Gap widget must be placed directly inside a Flex widget
I/flutter (12403): 
I/flutter (12403): The relevant error-causing widget was:
I/flutter (12403):   Gap file:///Users/mono/Git/gap/example/lib/main.dart:31:15
I/flutter (12403): 
I/flutter (12403): When the exception was thrown, this was the stack:
I/flutter (12403): #0      RenderGap.performLayout (package:gap/src/rendering/gap.dart:95:7)
I/flutter (12403): #1      RenderObject.layout (package:flutter/src/rendering/object.dart:1767:7)
I/flutter (12403): #2      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:111:13)
I/flutter (12403): #3      RenderObject.layout (package:flutter/src/rendering/object.dart:1767:7)
I/flutter (12403): #4      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:111:13)
I/flutter (12403): #5      RenderObject.layout (package:flutter/src/rendering/object.dart:1767:7)
I/flutter (12403): #6      RenderSliverList.performLayout (package:flutter/src/rendering/sliver_list.dart:193:27)

ListView x SliverGap

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ListView(
        children: const [
          SliverGap(100, color: Colors.red),
        ],
      ),
    );
  }

I/flutter (12403): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter (12403): The following assertion was thrown building NotificationListener<KeepAliveNotification>:
I/flutter (12403): A RenderRepaintBoundary expected a child of type RenderBox but received a child of type
I/flutter (12403): RenderSliverGap.
I/flutter (12403): RenderObjects expect specific types of children because they coordinate with their children during
I/flutter (12403): layout and paint. For example, a RenderSliver cannot be the child of a RenderBox because a
I/flutter (12403): RenderSliver does not understand the RenderBox layout protocol.
I/flutter (12403): 
I/flutter (12403): The RenderRepaintBoundary that expected a RenderBox child was created by:
I/flutter (12403):   RepaintBoundary ← IndexedSemantics ← NotificationListener<KeepAliveNotification> ← KeepAlive ←
I/flutter (12403):   AutomaticKeepAlive ← KeyedSubtree ← SliverList ← MediaQuery ← SliverPadding ← Viewport ←
I/flutter (12403):   IgnorePointer-[GlobalKey#633e1] ← Semantics ← ⋯
I/flutter (12403): 
I/flutter (12403): The RenderSliverGap that did not match the expected child type was created by:
I/flutter (12403):   SliverGap ← RepaintBoundary ← IndexedSemantics ← NotificationListener<KeepAliveNotification> ←
I/flutter (12403):   KeepAlive ← AutomaticKeepAlive ← KeyedSubtree ← SliverList ← MediaQuery ← SliverPadding ← Viewport
I/flutter (12403):   ← IgnorePointer-[GlobalKey#633e1] ← ⋯
I/flutter (12403): 
I/flutter (12403): The relevant error-causing widget was:
I/flutter (12403):   ListView file:///Users/mono/Git/gap/example/lib/main.dart:29:13
I/flutter (12403): 
I/flutter (12403): When the exception was thrown, this was the stack:
I/flutter (12403): #0      RenderObjectWithChildMixin.debugValidateChild.<anonymous closure> (package:flutter/src/rendering/object.dart:2916:9)
I/flutter (12403): #1      RenderObjectWithChildMixin.debugValidateChild (package:flutter/src/rendering/object.dart:2943:6)
I/flutter (12403): #2      SingleChildRenderObjectElement.insertChildRenderObject (package:flutter/src/widgets/framework.dart:5848:25)

letsar commented 4 years ago

Yep this is expected, since I created it only for Rows and Columns in the first time. But I have a working solution in my mind! Wait for me to have some time and I will update this package 😉.

letsar commented 4 years ago

Landed in the v1.2.0 🚀

letsar / gap

How to use Gap in ListView's children? #2

ListView x Gap

ListView x SliverGap