Hi I need context in many classes other than activity or fra

Question

Hi I need context in many classes other than activity or fragment I am passing it as a method parameter wherever required But I feel as per DI framework I should make app context available at all places For doing the same I found reference While along with this also found which says my old implementation is correct I AM CONFUSED disappointed Can anybody help

Cody Engel · Answer

It depends What are you using the `Context` instance for I ve found most project benefit from an interface `StringProvider` which has an implementation that relies on the `Context` This can be easily added to a dagger dependency graph but again it all depends on the use case Singleton isn t great but there are likely plenty of apps out there today which do that and functions perfectly well

Deepti M · Answer

I am using it mainly for fetching the resources shared pref external storage or similar things

Cody Engel · Answer

I would have a wrapper similar to the one I described one as `ResourceProvider` another as `PreferenceProvider` and a final one as `StorageProvider`

Deepti M · Answer

Yes agree singleton is not good as per standards but as a contradictory point it is far good than making unnecessary multiple copies of same similar instances

Cody Engel · Answer

Singletons tend to break down when you want to write unit or integration tests

Cody Engel · Answer

Not always because you can of course scope instances as a singleton but if those instances aren t constructor injected you ll usually have a bad time if you want to write any sort of functional tests

Deepti M · Answer

Yes have created all the providers as you said and need context in all of them

Cody Engel · Answer

Are you using a DI framework If so which one and is there a snippet you can share to outline where you are getting hung up

Deepti M · Answer

Using Koin

Cody Engel · Answer

What does your `startKoin` function look like

Deepti M · Answer

```startKoin androidLogger androidContext this BaseApplication modules allModules ```

Cody Engel · Answer

Can you share a snippet of a module you re having difficulty providing the context with

Deepti M · Answer

No ```androidContext ``` is available in all modules

Deepti M · Answer

and I can pass it to any class

Cody Engel · Answer

I m not following the issue then

Deepti M · Answer

I am working on Videos in my app and have Video kt model

Deepti M · Answer

This is one method of that model ``` fun getVideoUrl context Context String val isTab = context resources getBoolean R bool isTab val isPortrait = context resources configuration orientation == Configuration ORIENTATION PORTRAIT var resolution = PreferenceHelper readSelectedResolution context if resolution == CamcorderProfile QUALITY 2160P resolution = if TextUtils isEmpty video2kShortPortrait || TextUtils isEmpty video2kShortLandscape CamcorderProfile QUALITY 1080P else return if isTab amp amp isPortrait video2kShortLandscape else video2kShortPortrait var videoType String = context applicationContext let DeviceHelper getVideoType it resolution if IDevice SMALL TABS == videoType amp amp isPortrait videoType = IDevice SMALL TABS PORTRAIT else if IDevice LARGE TABS == videoType amp amp isPortrait videoType = IDevice LARGE TABS PORTRAIT var videoUrl String = getVideoByType PreferenceHelper readSelectedVideoQuality context videoType if TextUtils isEmpty videoUrl videoUrl = getVideoByType IDevice QUALITY HD videoType return videoUrl ```

Deepti M · Answer

Now here I need PreferenceProvider StorageProvider resources etc So I am confused how to handle it

Cody Engel · Answer

You could have a `VideoFactory` which is part of your Koin dependency graph Then in places which need to create a `Video` they could invoke `VideoFactory` to create a new instance of it I m not sure what the exact parameters are it could be setup something like this ```VideoFactory preferenceProvider PreferenceProvider storageProvider StorageProvider fun create specific properties for model Video return Video preferenceProvider storageProvider specific properties for model ```

Cody Engel · Answer

Then instead of passing context to the function the model would already have the providers it needs to generate the data

Deepti M · Answer

O Great

Deepti M · Answer

Thanks for this suggestion

Cody Engel · Answer

Yeah you re welcome

Deepti M · Answer

Actually I am new to Kotlin as well as Koin and was not clear with this feature

Deepti M · Answer

Trying to do this factory integration May I bother you again if gets blocked anywhere Thanks

Cody Engel · Answer

Unpopular opinion depending on who is reading this but I would try to shift towards Dagger when you can It has a bit more going on than Koin but Google has been creating good tutorials for it and you get a bit more control over your dependencies <https codelabs developers google com codelabs android dagger 0>

Cody Engel · Answer

Happy to help when I m online I am signing off for the evening but I m typically available 9 5 CT 06 00 I believe

Deepti M · Answer

Oh I was trying with Dagger first but wen came across with <https insert koin io> in standard documents of Kotlin then decided to goo for Koin

Pablo L. · Answer

I generally agree on what Cody is saying but I d like to point out how important is as a rule of thumb to keep your logic free of Android dependencies e g Context Following a typical Clean Architecture approach <https fernandocejas com 2018 05 07 architecting android reloaded > the central layer should not depend on any Android feature so that it can be easily unit tested

venomvendor · Answer

```startKoin androidLogger androidContext this BaseApplication lt Making context glolbally available modules allModules fun getVideoUrl String Get context injected during initialization val context Context = get ```

venomvendor · Answer

^ FYI The above makes hard to unit test You will rely on UI tests or roboelectric

Ahmed Ibrahim · Answer

Even though this approach is totally valid it has one caveat in ResourcesProvider in case you tried to resolve string from it It won t work if your app has custom localization requirements e g device language is English but the app needs to be displayed in French or other languages then you ll need an Activity context for that <https kotlinlang slack com archives C0B8M7BUY p1587075968008000 thread ts=1587074955 007300 amp cid=C0B8M7BUY>

Cody Engel · Answer

< Ahmed Ibrahim> I don t think that s an accurate statement partly because I ve used this approach with localized apps without issues The main difference between application and activity contexts are themes As a clarifying point though I tend to have a `StringProvider` which just provides strings the other ones from that post are other interfaces you could extract as well

Ahmed Ibrahim · Answer

< Cody Engel> Sorry I forgot to add that depends on how do you implement the language switching if you do `Process killProcess ` to destroy the application and to reload everything then yeah application context would work but if you just do`activity recreate ` then you will need to use the activity context to load the newly configured strings At least that how it did work for me

Cody Engel · Answer

I ve only supported language switching via the phone settings which has worked fine I wrote a small Activity which worked for switching between english and german via the phone s language settings ```class LocalizedActivity AppCompatActivity override fun onCreate savedInstanceState Bundle super onCreate savedInstanceState setContentView TextView baseContext also it text = application getString R string hello ```

Ahmed Ibrahim · Answer

I m afraid my use case is different which is device language from phone settings is English but the app language itself is displayed in german

Cody Engel · Answer

That seems like an interesting use case

Ahmed Ibrahim · Answer

Changing the language settings from the Phone will definitely work with `ResourceProvider` that has application context injected the problem becomes when your application has a custom `resources configuration` than what s coming from the Phone settings Then you ll need activity context to resolve strings correctly Again that s how it did work for me I might ve been doing something wrong that made things didn t work with application context man shrugging

Cody Engel · Answer

I can t think of a situation where I d want to override how the system is intended to work though I could be missing something as the default language for my apps has been english but I always assumed the default language could be whatever you d want it to be

Ahmed Ibrahim · Answer

Yeah I think it s wide spread in e commerce apps and in Europe here also it s wide spread due to different localization requirements across regions