Error: 'dependOnInheritedWidgetOfExactType' was called on null

[smkhalsa]

I'm getting the following error when calling the Router.generator method:

The following NoSuchMethodError was thrown building IconTheme(color: Color(0xdd000000)):
The method 'dependOnInheritedWidgetOfExactType' was called on null.
Receiver: null
Tried calling: dependOnInheritedWidgetOfExactType<_InheritedTheme>()

The relevant error-causing widget was
    MaterialApp 
lib/app.dart:30
When the exception was thrown, this was the stack
#0      Object.noSuchMethod  (dart:core-patch/object_patch.dart:53:5)
#1      Theme.of 
package:flutter/…/material/theme.dart:128
#2      Router.matchRoute.<anonymous closure> 
package:fluro/src/router.dart:130
#3      Router.matchRoute 
package:fluro/src/router.dart:183
#4      Router.generator

It looks like this change may be the source of the bug.

Is there a reason that null is passed for BuildContext here?

[fatimahossny]

I got this err so at last I tried example existed with fluro package , when I applyedtransitionType: TransitionType.native and it throw the same err , any update for that ?

[jlubeck]

I'm getting this on web when going straight to a page that is not the initial route

[smasinde]

This was also happening to me when my initialRoute string was anything other than '/'. e.g. '/login'. Changed that and all good. 🤷🏾‍♂️

[zinwalin]

same here.

══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════ The following NoSuchMethodError was thrown building IconTheme(color: Color(0xdd000000)): The method 'dependOnInheritedWidgetOfExactType' was called on null. Receiver: null Tried calling: dependOnInheritedWidgetOfExactType<_InheritedTheme>()

[hamberluo]

same error, any update?

[brianschardt]

same error any updates?? I get an error only on flutter for web when I have a parameter in the url

http://url.com/profile/1

[brianschardt]

I have a good fix for this is an update is not push in the next few days I will publish my own temp package that others can pull from.

[brianschardt]

here the forked package is. hopefully fluro fixes this soon. https://pub.dev/packages/fluro_fork

[pmorenov]

Hi @lukef

This has become a blocking issue after updating to Flutter 1.17 and Fluro 1.6.3

@brianschardt 's fork (thanks!) seems to do the trick. Any chance for an official fix?

Thank you

[teneon]

I am using Flutter 1.17.1 and Fluro 1.6.3. In my case, both: transitionType: TransitionType.nativeModal and transitionType: TransitionType.native are preventing navigation from working. The error is output like this: The method 'dependOnInheritedWidgetOfExactType' was called on null.

I ran into this error in Android Emulator, when i was testing the "Breaking Bapp" app:

If you would like to take a look, simply git clone (master branch) and try "flutter run" it. After it loads, click on any of the items in the "Characters" tab or in the "Quotes" tab. Because of this error navigation doesn't work, error is printed in the console instead.

If i comment out transitionType, it works. Any idea when this issue could be fixed?

Best regards, Jim

[fatimahossny]

You can fork it and update it like here https://github.com/theyakka/fluro/pull/166/commits/ca2e1d927f4b68e8824d5d5569925f2a4a6a587f it works fine for me as i need native transition

[mattetom]

here the forked package is. hopefully fluro fixes this soon. https://pub.dev/packages/fluro_fork

With this forks works correctly! Thsnk you very much @brianschardt

[zinwalin]

here the forked package is. hopefully fluro fixes this soon. https://pub.dev/packages/fluro_fork

awesome, thanks heaps.

[neckaros]

Thanks for the fork!

Is the Fluro package still maintained? it seems like a pretty big issue with a simple solution available now for ~3 months

[tobytraylor]

Looks like the last commit was around the same time this was opened. Has this project been abandoned?

[lukepighetti]

Please see https://github.com/theyakka/fluro/issues/184 for an update about the current status of fluro

[lukepighetti]

I am not able to reproduce this. If this is still an issue would someone please post an MVCE and I'll be happy to reopen this.

[tobytraylor]

Can somebody using Fluro Fork post on here when they have confirmed the latest build of fluro doesn't have this issue?

[JagandeepBrar]

@tobytraylor @lukepighetti I was using fluro_fork and just tried changing to the original fluro package and am still running into this issue.

My project is open source, and can be reproduced on the v4.1.0+40100003 branch which I just attempted to switch back to the original package, available here: https://github.com/CometTools/LunaSea/tree/v4.1.0%2B40100003

You don't need to add any of the modules/software to see the problem, just open the drawer and attempt to open the settings page. You can view where I initialize the core router in core/router.dart, the settings router in modules/settings/core/router.dart and then each individual route definition can be followed through that file, as I define each route inside of each route file itself. I can produce a MVCE if necessary, but it occurs specifically with TransitionType.native being used. Attempted with a few other transition types, include FadeIn, material, and Cupertino and the problem does not occur, but I want to keep native transitions for now as I have not finished adopting Fluro across the entire application yet.

Also to note, I am also using the latest Flutter stable branch (1.22.2).

[JagandeepBrar]

The issue is relatively easy to identify, use the generator in your navigator and when it calls matchRoute on line 282, it passes a null BuildContext to the function (which is expected, since there is no context available).

Then on line 167 within matchRoute you attempt to access the platform type by calling if (Theme.of(buildContext).platform == TargetPlatform.iOS) {, which is what throws the error since buildContext is null.

The fluro_fork package remedied this by doing a check for a null context: if (buildContext == null || Theme.of(buildContext).platform == TargetPlatform.iOS) {. This could be considered non-ideal, since buildContext could be null for an Android device and it would still return a CupertinoPageRoute, and I saw you closed a pull request which checks the platform using the Platform class which requires dart:io which would break web support. But it is definitely still an issue, and a relatively big breaking issue at that.

[lukepighetti]

I'm unable to get null for buildContext except for when the first route / is pushed. So if you have seen null come in at another time I need a way to reproduce it otherwise I cannot provide assistance with this.

I pushed up https://github.com/lukepighetti/fluro/commit/e341fea57c7064f813e57ade807b2910f7cbdb2a but I'm concerned that if you're getting null values regularly then this will just break all transitions instead of providing relief on the first build which was the intention.

TLDR: I still need an MVCE to be able to provide assistance.

[JagandeepBrar]

@lukepighetti Here is an MVCE, everything is contained within the main.dart file: https://github.com/JagandeepBrar/fluro-issue-154-MVCE

Let me know if you need anything else on my side.

Also, just cloned and locally referenced the most recent commit in fluro and the error still occurs. These changes are not in the repository, however.

[JagandeepBrar]

Is there even a need to separate the cases when using TransitionType.native?

When reading the MaterialPageRoute class documentation, it says:

A modal route that replaces the entire screen with a platform-adaptive transition.

For Android, the entrance transition for the page slides the route upwards and fades it in. The exit transition is the same, but in reverse.

The transition is adaptive to the platform and on iOS, the route slides in from the right and exits in reverse. The route also shifts to the left in parallax when another page enters to cover it. (These directions are flipped in environments with a right-to-left reading direction.)

Maybe this is new since fluro was originally developed, but testing it personally on iOS and Android devices, using TransitionType.material does in-fact keep the platform-specific transition type.

[JagandeepBrar]

I have created a PR that simply removes the platform check and always uses MaterialPageRoute. I tested it on iOS 14.0-14.2 and Android 9-11: https://github.com/lukepighetti/fluro/pull/191

[lukepighetti]

Merged, thank you so much!