marquee icon indicating copy to clipboard operation
marquee copied to clipboard

null reference error when widget height is unconstrained

Open xmine64 opened this issue 3 years ago • 2 comments

Hey. I have no idea why is this happening, but when I put Marquee directly in my widget tree instead of Text widget it gives a null reference with a long call stack:

═════ Exception caught by rendering library ═════════════════════════════════
Null check operator used on a null value
The relevant error-causing widget was
CustomScrollView
lib\pages\subtitle_details.dart:182
════════════════════════════════════════════════════════════════════════════════
E/flutter (31099): [ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: Null check operator used on a null value
E/flutter (31099): #0      ScrollPosition.minScrollExtent
package:flutter/…/widgets/scroll_position.dart:136
E/flutter (31099): #1      ScrollPosition._updateSemanticActions
package:flutter/…/widgets/scroll_position.dart:634
E/flutter (31099): #2      ScrollPosition.notifyListeners
package:flutter/…/widgets/scroll_position.dart:929
E/flutter (31099): #3      ScrollPosition.forcePixels
package:flutter/…/widgets/scroll_position.dart:377
E/flutter (31099): #4      ScrollPositionWithSingleContext.jumpTo
package:flutter/…/widgets/scroll_position_with_single_context.dart:198
E/flutter (31099): #5      ScrollController.jumpTo
package:flutter/…/widgets/scroll_controller.dart:173
...
E/flutter (31099): #8      SchedulerBinding._invokeFrameCallback
package:flutter/…/scheduler/binding.dart:1144
E/flutter (31099): #9      SchedulerBinding.handleDrawFrame
package:flutter/…/scheduler/binding.dart:1090
E/flutter (31099): #10     SchedulerBinding._handleDrawFrame
package:flutter/…/scheduler/binding.dart:998
E/flutter (31099): #11     _rootRun (dart:async/zone.dart:1354:13)
E/flutter (31099): #12     _CustomZone.run (dart:async/zone.dart:1258:19)
E/flutter (31099): #13     _CustomZone.runGuarded (dart:async/zone.dart:1162:7)

═════ Exception caught by scheduler library ═════════════════════════════════
Null check operator used on a null value
════════════════════════════════════════════════════════════════════════════════
E/flutter (31099): #14     _invoke (dart:ui/hooks.dart:163:10)
E/flutter (31099): #15     PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:259:5)
E/flutter (31099): #16     _drawFrame (dart:ui/hooks.dart:126:31)
E/flutter (31099):
E/flutter (31099): [ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: Null check operator used on a null value
E/flutter (31099): #0      RenderViewportBase.hitTestChildren
package:flutter/…/rendering/viewport.dart:703
E/flutter (31099): #1      RenderBox.hitTest
package:flutter/…/rendering/box.dart:2414
E/flutter (31099): #2      RenderProxyBoxMixin.hitTestChildren
package:flutter/…/rendering/proxy_box.dart:131
....
E/flutter (31099): #84     GestureBinding._handlePointerDataPacket
package:flutter/…/gestures/binding.dart:279
E/flutter (31099): #85     _rootRunUnary (dart:async/zone.dart:1370:13)
E/flutter (31099): #86     _CustomZone.runUnary (dart:async/zone.dart:1265:19)
E/flutter (31099): #87     _CustomZone.runUnaryGuarded (dart:async/zone.dart:1170:7)
E/flutter (31099): #88     _invoke1 (dart:ui/hooks.dart:182:10)
E/flutter (31099): #89     PlatformDispatcher._dispatchPointerDataPacket (dart:ui/platform_dispatcher.dart:282:7)
E/flutter (31099): #90     _dispatchPointerDataPacket (dart:ui/hooks.dart:96:31)

But when I put my widget in a SizedBox with a fixed height, it works, but I need to know exact height of font to make it work in this way. scrolling axis is horizontal so it should not care about vertical bounds, so I guess it's a bug in marquee.

xmine64 avatar Jun 30 '21 14:06 xmine64

Duplicate of #62

I admit that's a limitation of the current API; afaik it can't be easily resolved without rewriting major parts of the package. 🙁

MarcelGarus avatar Jul 01 '21 10:07 MarcelGarus

+1

dhcracchiolo avatar Dec 07 '21 20:12 dhcracchiolo