Positioned Widget Causes Child To Disappear/Exception
2,875
As your log explains :
"constraints: BoxConstraints(0.0<=w<=Infinity, h=180.0)"
you have to define the width of the Container which is the parent of your Swiper. You have to also organize the items inside your stack which aren't positioned using rows and columns to keep its layout consistent across different screens.
add this line inside your Container :
width: MediaQuery.of(context).size.width,
this will make your Swiper fill the screen width, you can modify it to any other value to suit your design.
Author by
Admin
Updated on December 02, 2022Comments
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Admin over 1 year
I am currently learning Flutter and I am trying to position a carousel at the bottom of the screen using the Positioned widget in a Stack. Currently, the stack is a map, with the carousel on top of that. When I use the positioned widget to move the carousel to the bottom it disappears and I am met with this error.
I/flutter (19228): Another exception was thrown: 'package:flutter/src/rendering/object.dart': Failed assertion: line 1578 pos 12: '!_debugDoingThisLayout': is not true. I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#51ed3 relayoutBoundary=up4 NEEDS-LAYOUT NEEDS-PAINT Restarted application in 1,970ms. I/flutter (19228): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════ I/flutter (19228): The following assertion was thrown during performResize(): I/flutter (19228): Horizontal viewport was given unbounded width. I/flutter (19228): Viewports expand in the scrolling direction to fill their container.In this case, a horizontal I/flutter (19228): viewport was given an unlimited amount of horizontal space in which to expand. This situation I/flutter (19228): typically happens when a scrollable widget is nested inside another scrollable widget. I/flutter (19228): If this widget is always nested in a scrollable widget there is no need to use a viewport because I/flutter (19228): there will always be enough horizontal space for the children. In this case, consider using a Row I/flutter (19228): instead. Otherwise, consider using the "shrinkWrap" property (or a ShrinkWrappingViewport) to size I/flutter (19228): the width of the viewport to the sum of the widths of its children. I/flutter (19228): I/flutter (19228): When the exception was thrown, this was the stack: I/flutter (19228): #0 RenderViewport.performResize.<anonymous closure> (package:flutter/src/rendering/viewport.dart:1155:15) I/flutter (19228): #1 RenderViewport.performResize (package:flutter/src/rendering/viewport.dart:1182:6) I/flutter (19228): #2 RenderObject.layout (package:flutter/src/rendering/object.dart:1619:9) I/flutter (19228): #3 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #4 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #5 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #6 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #7 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #8 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #9 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #10 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #11 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #12 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #13 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #14 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #15 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #16 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #17 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #18 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #19 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #20 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #21 RenderConstrainedBox.performLayout (package:flutter/src/rendering/proxy_box.dart:258:13) I/flutter (19228): #22 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #23 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:549:15) I/flutter (19228): #24 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #25 MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:142:11) I/flutter (19228): #26 _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:339:7) I/flutter (19228): #27 MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:212:7) I/flutter (19228): #28 RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:356:14) I/flutter (19228): #29 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #30 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #31 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #32 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #33 _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1188:11) I/flutter (19228): #34 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #35 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #36 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #37 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #38 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #39 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #40 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #41 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #42 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #43 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #44 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #45 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #46 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #47 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #48 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #49 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #50 RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2881:13) I/flutter (19228): #51 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #52 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:510:15) I/flutter (19228): #53 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #54 __RenderTheatre&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #55 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #56 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #57 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #58 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #59 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #60 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #61 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #62 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #63 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #64 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #65 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #66 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #67 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #68 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #69 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #70 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #71 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #72 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #73 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #74 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #75 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #76 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #77 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #78 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #79 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #80 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #81 RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2881:13) I/flutter (19228): #82 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #83 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:510:15) I/flutter (19228): #84 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #85 __RenderTheatre&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #86 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #87 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #88 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #89 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #90 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #91 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #92 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #93 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #94 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #95 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13) I/flutter (19228): #96 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7) I/flutter (19228): #97 RenderView.performLayout (package:flutter/src/rendering/view.dart:147:13) I/flutter (19228): #98 RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1509:7) I/flutter (19228): #99 PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:768:18) I/flutter (19228): #100 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:281:19) I/flutter (19228): #101 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:677:13) I/flutter (19228): #102 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:219:5) I/flutter (19228): #103 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15) I/flutter (19228): #104 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9) I/flutter (19228): #105 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.scheduleWarmUpFrame.<anonymous closure> (package:flutter/src/scheduler/binding.dart:751:7) I/flutter (19228): #107 _Timer._runTimers (dart:isolate/runtime/libtimer_impl.dart:382:19) I/flutter (19228): #108 _Timer._handleMessage (dart:isolate/runtime/libtimer_impl.dart:416:5) I/flutter (19228): #109 _RawReceivePortImpl._handleMessage (dart:isolate/runtime/libisolate_patch.dart:171:12) I/flutter (19228): (elided one frame from package dart:async) I/flutter (19228): I/flutter (19228): The following RenderObject was being processed when the exception was fired: I/flutter (19228): RenderViewport#90797 NEEDS-LAYOUT NEEDS-PAINT I/flutter (19228): creator: Viewport ← _ScrollableScope ← IgnorePointer-[GlobalKey#3c2b1] ← Semantics ← Listener ← I/flutter (19228): _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#cd194] ← I/flutter (19228): _ScrollSemantics-[GlobalKey#45621] ← RepaintBoundary ← CustomPaint ← RepaintBoundary ← I/flutter (19228): NotificationListener<ScrollNotification> ← ⋯ I/flutter (19228): parentData: <none> (can use size) I/flutter (19228): constraints: BoxConstraints(0.0<=w<=Infinity, h=180.0) I/flutter (19228): size: MISSING I/flutter (19228): axisDirection: right I/flutter (19228): crossAxisDirection: down I/flutter (19228): offset: _PagePosition#6c97d(offset: null, range: null..null, viewport: null, ScrollableState, I/flutter (19228): PageScrollPhysics -> ClampingScrollPhysics, IdleScrollActivity#73c09, ScrollDirection.idle) I/flutter (19228): anchor: 0.0 I/flutter (19228): This RenderObject had the following child: I/flutter (19228): RenderSliverFillViewport#ce224 NEEDS-LAYOUT NEEDS-PAINT I/flutter (19228): ════════════════════════════════════════════════════════════════════════════════════════════════════ I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderViewport#90797 NEEDS-LAYOUT NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderViewport#90797 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderIgnorePointer#598aa relayoutBoundary=up11 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderSemanticsAnnotations#4c977 relayoutBoundary=up10 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderPointerListener#2c082 relayoutBoundary=up9 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderSemanticsGestureHandler#e6e8c relayoutBoundary=up8 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: _RenderScrollSemantics#92ccd relayoutBoundary=up7 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#443e3 relayoutBoundary=up6 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderCustomPaint#4e459 relayoutBoundary=up5 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#954aa relayoutBoundary=up4 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderDecoratedBox#1354c relayoutBoundary=up3 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderConstrainedBox#b5d9f relayoutBoundary=up2 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderDecoratedBox#1354c relayoutBoundary=up3 I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#954aa relayoutBoundary=up4 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderConstrainedBox#b5d9f relayoutBoundary=up2 I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderDecoratedBox#1354c relayoutBoundary=up3 I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#954aa relayoutBoundary=up4 NEEDS-PAINT I/flutter (19228): Another exception was thrown: 'package:flutter/src/rendering/object.dart': Failed assertion: line 1578 pos 12: '!_debugDoingThisLayout': is not true. I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderDecoratedBox#1354c relayoutBoundary=up3 I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#954aa relayoutBoundary=up4 NEEDS-PAINT I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderDecoratedBox#1354c relayoutBoundary=up3 I/chatty (19228): uid=10100(com.example.mapview) Thread-2 identical 13 lines I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderDecoratedBox#1354c relayoutBoundary=up3 I/flutter (19228): Another exception was thrown: 'package:flutter/src/rendering/object.dart': Failed assertion: line 1578 pos 12: '!_debugDoingThisLayout': is not true. I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderDecoratedBox#1354c relayoutBoundary=up3 I/flutter (19228): Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#954aa relayoutBoundary=up4 NEEDS-PAINTHere is the code of my Stack
return new MaterialApp( home: Scaffold( appBar: new AppBar(title: new Text("Commonwealth Walkway Offline Map")), body: Stack( children: <Widget>[ FlutterMap( mapController: mapController, options: new MapOptions( center: new LatLng(51.1747, -115.56934), minZoom: 13.0, maxZoom: 16.0, zoom: 14.0, swPanBoundary: LatLng(51.16968, -115.58628), nePanBoundary: LatLng(51.1883, -115.5516), ), layers: [ new TileLayerOptions( offlineMode: true, maxZoom: 16, urlTemplate: "assets/map/banff/{z}/{x}/{y}.png", ), new MarkerLayerOptions( markers: generateMarkers( markers, swiperController.move, _currentIndex, LatLng(51.17360, -115.57140), _direction)), //_currentLocation ], ), Positioned( bottom: 1.0, child: Container( color: Colors.blue, height: 150.0, child: Swiper( itemBuilder: (BuildContext context, index) { return Carousels(markers[index], _update); }, itemCount: markers.length, viewportFraction: 0.8, scale: 0.9, loop: false, controller: swiperController, onIndexChanged: (index) { setState(() { _currentIndex = index; }); }, ), ), ) ], ), ), );The Swiper/Carousel package can be found here: https://pub.dartlang.org/packages/flutter_swiper#-readme-tab-