Images are not loaded after couple of restarts #40

mig35 · 2018-04-20T10:14:07Z

I guess this is a cause of the #38 #36 #35

This is a stacktrace of the error:

E/flutter ( 2853): 'package:flutter/src/painting/image_stream.dart': Failed assertion: line 362 pos 12: '_codec != null': is not true.
E/flutter ( 2853): #0      _AssertionError._doThrowNew (dart:core/runtime/liberrors_patch.dart:37:39)
E/flutter ( 2853): #1      _AssertionError._throwNew (dart:core/runtime/liberrors_patch.dart:33:5)
E/flutter ( 2853): #2      MultiFrameImageStreamCompleter._handleCodecReady (package:flutter/src/painting/image_stream.dart)
E/flutter ( 2853): #3      _RootZone.runUnary (dart:async/zone.dart:1381:54)
E/flutter ( 2853): #4      _FutureListener.handleValue (dart:async/future_impl.dart:129:18)
E/flutter ( 2853): #5      Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:637:45)
E/flutter ( 2853): #6      Future._propagateToListeners (dart:async/future_impl.dart:666:32)
E/flutter ( 2853): #7      Future._completeError (dart:async/future_impl.dart:489:5)
E/flutter ( 2853): #8      _SyncCompleter._completeError (dart:async/future_impl.dart:55:12)
E/flutter ( 2853): #9      _Completer.completeError (dart:async/future_impl.dart:27:5)
E/flutter ( 2853): #10     CachedNetworkImageProvider._loadAsync (package:cached_network_image/cached_network_image.dart)
E/flutter ( 2853): <asynchronous suspension>
E/flutter ( 2853): #11     CachedNetworkImageProvider.load (package:cached_network_image/cached_network_image.dart:462:16)
E/flutter ( 2853): #12     ImageProvider.resolve.<anonymous closure>.<anonymous closure> (package:flutter/src/painting/image_provider.dart:265:86)
E/flutter ( 2853): #13     ImageCache.putIfAbsent (package:flutter/src/painting/image_cache.dart:82:22)
E/flutter ( 2853): #14     ImageProvider.resolve.<anonymous closure> (package:flutter/src/painting/image_provider.dart:265:63)
E/flutter ( 2853): #15     SynchronousFuture.then (package:flutter/src/foundation/synchronous_future.dart:38:29)
E/flutter ( 2853): #16     ImageProvider.resolve (package:flutter/src/painting/image_provider.dart:263:30)
E/flutter ( 2853): #17     _ImageProviderResolver.resolve (package:cached_network_image/cached_network_image.dart:193:29)
E/flutter ( 2853): #18     _CachedNetworkImageState._resolveImage (package:cached_network_image/cached_network_image.dart:284:20)
E/flutter ( 2853): #19     _CachedNetworkImageState.didChangeDependencies (package:cached_network_image/cached_network_image.dart:261:5)
E/flutter ( 2853): #20     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3750:12)
E/flutter ( 2853): #21     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3600:5)
E/flutter ( 2853): #22     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #23     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #24     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #25     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #26     MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4742:32)
E/flutter ( 2853): #27     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #28     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #29     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #30     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #31     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #32     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #33     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #34     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #35     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3636:16)
E/flutter ( 2853): #36     Element.rebuild (package:flutter/src/widgets/framework.dart:3478:5)
E/flutter ( 2853): #37     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3605:5)
E/flutter ( 2853): #38     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3600:5)
E/flutter ( 2853): #39     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #40     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #41     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #42     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #43     Element.updateChild (package:fl
E/flutter ( 2853): [ERROR:topaz/lib/tonic/logging/dart_error.cc(16)] Unhandled exception:
E/flutter ( 2853): NoSuchMethodError: The getter '_value' was called on null.
E/flutter ( 2853): Receiver: null
E/flutter ( 2853): Tried calling: _value
E/flutter ( 2853): #0      Object.noSuchMethod (dart:core/runtime/libobject_patch.dart:46:5)
E/flutter ( 2853): #1      DateTime.difference (dart:core/runtime/libdate_patch.dart:183:54)
E/flutter ( 2853): #2      CacheManager._cleanCache (package:flutter_cache_manager/flutter_cache_manager.dart:129:45)
E/flutter ( 2853): <asynchronous suspension>
E/flutter ( 2853): #3      CacheManager._save (package:flutter_cache_manager/flutter_cache_manager.dart:75:11)
E/flutter ( 2853): <asynchronous suspension>
E/flutter ( 2853): #4      CacheManager.getFile (package:flutter_cache_manager/flutter_cache_manager.dart:243:5)
E/flutter ( 2853): <asynchronous suspension>
E/flutter ( 2853): #5      CachedNetworkImageProvider._loadAsync (package:cached_network_image/cached_network_image.dart:474:35)
E/flutter ( 2853): <asynchronous suspension>
E/flutter ( 2853): #6      CachedNetworkImageProvider.load (package:cached_network_image/cached_network_image.dart:462:16)
E/flutter ( 2853): #7      ImageProvider.resolve.<anonymous closure>.<anonymous closure> (package:flutter/src/painting/image_provider.dart:265:86)
E/flutter ( 2853): #8      ImageCache.putIfAbsent (package:flutter/src/painting/image_cache.dart:82:22)
E/flutter ( 2853): #9      ImageProvider.resolve.<anonymous closure> (package:flutter/src/painting/image_provider.dart:265:63)
E/flutter ( 2853): #10     SynchronousFuture.then (package:flutter/src/foundation/synchronous_future.dart:38:29)
E/flutter ( 2853): #11     ImageProvider.resolve (package:flutter/src/painting/image_provider.dart:263:30)
E/flutter ( 2853): #12     _ImageProviderResolver.resolve (package:cached_network_image/cached_network_image.dart:193:29)
E/flutter ( 2853): #13     _CachedNetworkImageState._resolveImage (package:cached_network_image/cached_network_image.dart:284:20)
E/flutter ( 2853): #14     _CachedNetworkImageState.didChangeDependencies (package:cached_network_image/cached_network_image.dart:261:5)
E/flutter ( 2853): #15     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3750:12)
E/flutter ( 2853): #16     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3600:5)
E/flutter ( 2853): #17     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #18     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #19     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #20     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #21     MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4742:32)
E/flutter ( 2853): #22     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #23     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #24     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #25     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #26     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #27     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #28     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #29     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #30     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3636:16)
E/flutter ( 2853): #31     Element.rebuild (package:flutter/src/widgets/framework.dart:3478:5)
E/flutter ( 2853): #32     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3605:5)
E/flutter ( 2853): #33     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3600:5)
E/flutter ( 2853): #34     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #35     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #36     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4637:14)
E/flutter ( 2853): #37     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
E/flutter ( 2853): #38     Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
E/flutter ( 2853): #39     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3636:16)
E/flutter ( 2853): #40     Element.rebuild (package:flutter/src/widgets/framework.dart:3478:5)
E/flutter ( 2853): #41     ComponentElement._firstBuild (package:flutter/src/widgets/f

Also I've found that error happened in this code:

    return new MultiFrameImageStreamCompleter(
        codec: _loadAsync(key).catchError((e) {
          if (errorListener != null) errorListener();
        }),
        scale: key.scale,
        informationCollector: (StringBuffer information) {
          information.writeln('Image provider: $this');
          information.write('Image key: $key');
        });

So in debugger I see that _loadAsync returns with error and then codec becomes null

Then I go deeper and found that error happens in cache_object.dart in method CacheObject.fromMap(String url, Map map) because map is null. Map is null because of CacheManager class and its _getSavedCacheDataFromPreferences method. Inside _keyCacheData we can found an empty string with null map.

To be clear _keyCacheData has "": null inside. I don't know why it is there, but this is the cause.

The text was updated successfully, but these errors were encountered:

jukbot · 2018-04-23T05:35:15Z

get the same issue, some image is loaded but the remain images are broken and throw error Failed assertion: line 362 pos 12: '_codec != null': is not true.

lemonboston · 2018-04-24T19:10:00Z

We have the same error.

It means in our case that when an image has been tried to load the first time in offline mode, thus resulting in error, it won't load ever again correctly even when reconnected.

As a workaround I have wrapped CachedNetworkImage and show the placeholder 'manually' when there is no connection. Connection is retrieved with InheritedWidget so this wrapper is rebuilt when connection is back, and delegates to CachedNetworkImage.
This of course means we don't show any image in offline mode even if they are cached, so it's not ideal.

renefloor · 2018-04-25T20:02:35Z

I am trying to understand what's going wrong, but I don't really understand it..

I tried to breakpoint the code when using an app offline, but it doesn't get past this code in CacheManager.getFile

    if (!_cacheData.containsKey(url)) {
      synchronized(_lock, () {
        if (!_cacheData.containsKey(url)) {
          _cacheData[url] = new CacheObject(url);
        }
      });
    }

I also found that the synchronized doesn't seem to work the way I expected and that the singleton design seems to be broken. I could not find any sources on how to make a Singleton when the initialization phase needs an await (is asynchronous).

I also suspect that the synchronized might be broken in dart 2.0.

mig35 · 2018-04-26T04:50:52Z

@renefloor you can create a quick fix my checking map for null in your code before pushing to CacheObject

Cyan101 · 2018-04-26T15:34:29Z

@lemonboston any chance you can share or PR?

renefloor · 2018-04-27T13:27:50Z

Could you check whether this is fixed in 0.4.1? I did multiple improvements, so I am not sure whether this case is fixed.

jonasbark · 2018-05-02T14:10:05Z

didn't see that happening again with 0.4.1

lemonboston · 2018-05-02T16:07:30Z

I don't see the exception with 0.4.1 either, although the issue with these steps still happens:

disconnect from network
open a screen with an image (doesn't load)
go back from screen, reconnect, open screen again
actual: image not loaded, expected: loads

But if I close and restart the app, then that particular image is loaded correctly (I don't know if that was the case with 0.4.0 as well or not).

@Cyan101 my workaround was not a fix for this library, just guarding CachedNetworkImageWidget in a way that it's not shown when there is no network. I used this lib for checking connection:
https://pub.dartlang.org/packages/connectivity

renefloor · 2018-05-03T13:15:20Z

@lemonboston that is indeed still a problem. See also the conversation in https://github.com/renefloor/flutter_cache_manager/issues/9 and issue #41.

pavel-ismailov · 2018-07-22T11:55:11Z

@renefloor

Why is that closed?
Am I understood right that you consider the bud related to Flutter sources flutter_cache_manager, not your library?

kadaha · 2018-08-03T18:29:39Z

Here is how i made it work for now

try to add this to the main or before :

import 'package:flutter_cache_manager/flutter_cache_manager.dart';
void main() async {
  CacheManager.getInstance();
.....
}

This will init the cache manager if its null so _cacheData will not be null :

static Future getInstance() async {
if (_instance == null) {
await synchronized(_lock, () async {
if (_instance == null) {
instance = new CacheManager.();
await _instance._init(); <----------------------------------
}
});
}
return _instance;
}

CacheManager._();

SharedPreferences _prefs;
Map<String, CacheObject> _cacheData;<-------------------------------(Not initialized )
DateTime lastCacheClean;

static Object _lock = new Object();

///Shared preferences is used to keep track of the information about the files
_init() async {
_prefs = await SharedPreferences.getInstance();
_getSavedCacheDataFromPreferences();<---------------------------------------------
_getLastCleanTimestampFromPreferences();
}

_getSavedCacheDataFromPreferences() {
//get saved cache data from shared prefs
var jsonCacheString = _prefs.getString(_keyCacheData);
_cacheData = new Map(); <------------------------------------------------------ (initialized)
if (jsonCacheString != null) {
Map jsonCache = const JsonDecoder().convert(jsonCacheString);
jsonCache.forEach((key, data) {
if (data != null) {
_cacheData[key] = new CacheObject.fromMap(key, data);
}
});
}
}

renefloor closed this as completed May 3, 2018

ThinkDigitalSoftware mentioned this issue Jun 18, 2018

MissingPluginException(No implementation found for method getAll on channel flutter: plugins.flutter.io/shared_preferences) #50

Closed

mayurprajapati mentioned this issue Mar 3, 2019

Error when passing the invalid argument #137

Closed

xiaoxiaocainiao mentioned this issue Mar 14, 2019

Unhandled Exception: SocketException: OS Error: Connection reset by peer, errno = 104, address = www.wangyan.im, port = 38400 #145

Closed

xiaodeng2014 mentioned this issue Oct 18, 2019

Error: The method 'CachedNetworkImageProvider.load' has fewer positional arguments than those of overridden method 'ImageProvider.load' #270

Closed

DominicOrga mentioned this issue Dec 1, 2020

Images not rendering after updating to 2.4.0 #514

Closed

sandeep9607 mentioned this issue May 9, 2021

CacheManager: Failed to download file from url #336

Open

mdmota mentioned this issue Jul 22, 2023

Exception: Invalid image data. Error thrown Instance of 'ErrorDescription'. #859

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Images are not loaded after couple of restarts #40

Images are not loaded after couple of restarts #40

mig35 commented Apr 20, 2018 •

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jukbot commented Apr 23, 2018

lemonboston commented Apr 24, 2018

renefloor commented Apr 25, 2018

mig35 commented Apr 26, 2018

Cyan101 commented Apr 26, 2018

renefloor commented Apr 27, 2018

jonasbark commented May 2, 2018

lemonboston commented May 2, 2018 •

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renefloor commented May 3, 2018

pavel-ismailov commented Jul 22, 2018

kadaha commented Aug 3, 2018

Images are not loaded after couple of restarts #40

Images are not loaded after couple of restarts #40

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mig35 commented Apr 20, 2018 • edited Loading

jukbot commented Apr 23, 2018

lemonboston commented Apr 24, 2018

renefloor commented Apr 25, 2018

mig35 commented Apr 26, 2018

Cyan101 commented Apr 26, 2018

renefloor commented Apr 27, 2018

jonasbark commented May 2, 2018

lemonboston commented May 2, 2018 • edited Loading

renefloor commented May 3, 2018

pavel-ismailov commented Jul 22, 2018

kadaha commented Aug 3, 2018

mig35 commented Apr 20, 2018 •

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lemonboston commented May 2, 2018 •

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