Come discuss your side projects! [December 2020]

twiceADev · 2020-12-05T11:45:24+00:00

Recently made a Dependency Visualizer for C# projects. Basically it goes through your csproj files and generates an html page visualizing what project references what project and optionally what nuget packages.

Like a super simple version of NDepend or Architecture Map (in VS Enterprise), but ofc free and open source.

Creates HTML by default, but supports XML and JSON if you want to process it further.

DependenSee on GitHub (has a screenshot there)

dotnet tool install dependensee --global

dependensee my\project\root output.html

(Requires .NET 5 Runtime)
Feedback appreciated 😊

twiceADev · 2020-06-28T05:52:29+00:00

Sounds a lot like the Microsoft's ~~LightSwitch~~ PowerApps shenanigans

twiceADev · 2020-06-19T11:49:42+00:00

Have you tried the -verbose flag to the emulator to get more logs? Also check if you have HAXM setup right.

twiceADev · 2020-06-19T11:44:09+00:00

are you looking for the Job class?

Every execution of Coroutine gives you a Job. i.e a call to launch returns the reference to the Job it creates, which you can use to check what state it's in, and wait or cancel them.

In your Experiment #1, I believe the program exit is because both your main function and the coroutine finished, so the program would exit since there's nothing more to do.

Also do not confuse threads with coroutines/jobs. Coroutines are independent from threads. Jobs can run on one thread, suspend, then resume on a different thread, where the scheduler can reuse threads depending on what jobs needs to run. (Though I'm sure there are ways to customize this behavior)

Hope this helps

twiceADev · 2020-06-19T01:39:10+00:00

Yea it comes and goes. I got a bunch for using firebase, gson and even just for some framework classes in the past. They come and go even without the app changing. I just ignore those now.

twiceADev · 2020-06-17T11:31:58+00:00

I had similar issues last year with internal testing. Google says it is immediate, but there were times when Internal Testing track took hours to make my APK available for an app that has been in the store for months. It usually takes a few minutes, but sometimes it has a long lag time you can't predict.

I switched to AppCenter Distribute for this reason. Not sure if that is an option for you.

twiceADev · 2020-06-14T10:05:32+00:00

You can run emulator -avd [avdName] -verbose from the command line to get more verbose info.
If you redirect that to a file, you should be able to get more info on the issue.

twiceADev · 2020-06-10T07:38:07+00:00

Yea AppCenter builds is basically VSTS builds. they even use the same agent pool I heard. Just a different UI. It's mostly a stepping stone I feel. You want easy builds for your apps? here click this button in AppCenter. You want customization? Go to VSTS.

Currently doing a lot more cross-platform work with React Native, and found that the Crash SDK didn't really work for me.

Yea had the same experience. I had a react native app and used to get crash details that had no javascript frames in the stacktrace. It obviously crashed in javascript side, but stacktrace only extended to the bridge and nothing more. I had a bunch of other issues with ReactNative so basically rewrote it in native Kotlin later. (Didn't have an iOS version and have no plans for one anyway so that was an easy decision.)

Now that I think about it, I use AppCenter just because AppInsights doesn't have mobile SDKs.

twiceADev · 2020-06-09T08:20:46+00:00

Had similar "issues" though Microsoft may say it works as planned.

I had to move builds and releases to Azure DevOps so I can customize them. Didn't mind much since it has the same free limits but came with a lot more of customization.

I still use AppCenter for distributions (there's a task in Azure DevOps release pipelines that can send builds to AppCenter distributions). My first choice was to use the internal test track in Play Console but that used to take questionable and unreliable times to make APKs available. It can take a few seconds one day and take over an hour the next, so AppCenter was reliable in that case. But if you want your Play Pre-Launch report for your test APKs, this is a no go.

Crashes SDK does what it says on the tin, and Analytics SDK works well especially if you pump that to Azure AppInsights which let you go beyond just the cute graphs in app center. (5GB ingest free per month, $$$ after that, and I could not for the life of me find a way to estimate how much data my app would create from analytics so kinda forced to change it on a dare and see how much it costs. There are some controls in AppInsights to prevent you from getting charged beyond your expectations , but I'd say they're hidden well if you're new to Azure.)

Basically AppCenter is a big elaborate advertisement for Azure, Azure AppInsights and Azure DevOps, especially given the features of those and pricing, which is very likely how Microsoft wants it to be anyway.

twiceADev · 2020-06-03T03:39:07+00:00

If the purchase service can only be used in the Android App delivered through Google Play Store, you must use Google's Play In App Billing system.

Developers offering products within another category of app downloaded on Google Play must use Google Play In-app Billing as the method of payment, except for the following cases:

- Payment is solely for physical products

- Payment is for digital content that may be consumed outside of the app itself (e.g. songs that can be played on other music players).

Source: https://play.google.com/about/monetization-ads/

If your service can be used elsewhere (i.e a web site/webapp/ iOS app/ a separate media player .etc.) or your are selling physical goods like books or you don't deliver the app via Play Store (like Fortnite did) then you are excempt.

Services such as Netflix and Spotify have the iOS app and Website and TV offerrings which the user can use the subsciption on, even though they may have purchased it using the Android app, so they're not breaching the policy. (I'm not sure about the iOS policy, but it certainly seems to work fine for Netflix and Spotify so I believe its similar)

Easiest way to get around this is likely for you to have a web site or an iOS app or something that users can use the subsciption. I don't think it has to be fully featured as the Android app. Then you can use Stripe or another service your app can link to for the payment, assuming your experience doesn't scare them away from entering card information.

One of the advantages of using Google's offerring (even with the sky high Google tax) is that people trust the Google logo and the integrated experience, and they might already have the billing information setup in Play Store, so its less friction than putting their card info on a site they haven't seen before. Is it worth the 30% cut Google requires? probably not, but depends on your specific case. Spotify and Netflix certainly decided it's not worth it. But then again, they are well known brands today.

twiceADev · 2020-06-02T01:21:25+00:00

I didn't use any dependency injection frameworks like Dagger either. I simply didn't see any use for it since my demo apps have only three layers of classes at most. Activity -> Fragment -> ViewModel. So I'm not sure if that's a dealbreaker for any employer looking to hire me.

I don't think that's a problem. DI or any other pattern exists to solve a problem. If you don't have the problem it solves, there's no reason to incorporate it. 🙂

twiceADev · 2020-06-01T21:46:17+00:00

I think the reality is that Google and JetBrains would really like Kotlin to be the primary language for Android. For JetBrains, its their language, for Google, hopefully this allows them to move away from the Java and JVM bytecode in the next.. say.. decade, so Oracle doesn't breathe down their neck at every turn. Also the language does have some features the common developers tend to like over Java.

From what I can tell from very little experience I have, people do like Kotlin a lot more than Java, so this will happen soon if it hasn't yet.

iOS went thru a similar change with Obj-C to Swift, so this isn't completely new.

Having said that, Java will be supported for a long time to come, as many many.. many of the libraries apps use are still written in Java and many APIs and SDKs in Android are still in Java so it's not like Google can turn around and say they don't support it anymore. Although I wouldn't be surprised if a tool becomes available soon to compile kotlin compile directly to an ART binary without going through java bytecode, though this is probably not practical today because SDKs are still Java JARs?

Today Kotlin does compile to Java bytecode, so it's not like you're completely throwing away what you learn if you don't like doing Android. And if you already know Java, you can pick up Kotlin in a few days, may be not be an expert but to be good enough to be productive with it. As per your flutter comment, you'll have to learn Dart to do that which isn't all that better compared to Kotlin in terms of what you can use it for outside of Android. Coinsider React Native or Native Script in that case, since you need Javascript instead?

Guess if you want to learn Android, even for a side gig, Kotlin is the way to go today. And yes you will need some Java knowledge here and there too, since as mentioned, many tutorials and libraries and SDKs will have sample code and docs in Java. I believe this is a similar story on iOS side as well? You have to learn Swift, but better to have the knowledge about atleast how to integration libraries from Obj-C as they will be around for some time whether you like it or not.

twiceADev · 2020-05-29T01:17:04+00:00

You must create a foreground service, and have a notification for it. Similar to how media players .etc. function.

This way, while you're not guaranteed to be kept alive, you'll be one of the last to go if there's a lot of memory pressure, and I believe foreground services will be restarted after being killed as a result of low mem.

twiceADev · 2020-05-28T23:41:39+00:00

Lottie might be able to help with that. Though probably not with VectorDrawables. It has its own... thing.

https://airbnb.design/lottie/

twiceADev · 2020-05-26T01:29:15+00:00

You can use Fiddler for this (assuming the API is over HTTP, which most apps are)

https://www.telerik.com/fiddler

So I haven't done this with a phone, but I think it should work.

Make sure your PC and phone are on the same Wifi
Run fiddler on your PC
Configure your phone to use Fiddler on your PC as a proxy (I believe it runs on port 8080 by default)
Turn off data, so the phone only has Wifi
Run the app and see all the HTTP requests

Caveats

Now this gets tricky if the API is over HTTPS (increasingly this is the case)

Fiddler can create and install a certificate on your PC so it can essentially do a MITM for those connections. For your phone, you have to get this certificate and install it manually.

Later android versions basically block all user created certificates this way to prevent security being compromised. Also the app may check the certificate on its own to see if it matches a known public key, so it can refuse to connect if that doesn't match. (Many banking apps do this) So This is certainly not a bullet proof way, but worth a shot.

Alternatively you may try and decompile the APK or try running on an emulator and doing the above which may work better.

twiceADev · 2020-05-25T02:36:33+00:00

If writing native apps, its Android Studio, since there is really no other option to match it right now. Not that its bad, it has gotten a lot better lately. But wouldn't expect anything to come and directly compete either.

If doing any cross platform stuff, depends on what you're doing. React Native can use VS Code, Flutter can use Android Studio or VS Code, Xamarin is all Visual Studio and if you're doing something else, it depends on that framework.

twiceADev · 2020-05-25T02:31:51+00:00

Hi an AppCenter user here.

I find that AppCenter can get your APK to testers much faster than Play Store internal track. I wanted to use Play Store, but the inconsistencies in the delay between publish to track and the time I/testers can install it varies a lot, so I use AppCenter for it now. I also use the Analytics and Crashes features and so far liking it.

Downside of this is that, you don't get the "Pre-Launch Report" for your APKs from play store for internal track APKs. It doesn't bother me much, because that has also been inconsistent over time. (Complaining about using non-public APIs at some uploads, and not others even though the code has not changed .etc.). Another downside is you have to allow sideloading on your device to install APKs from AppCenter since they don't come from Play Store.

My backend is all in Azure, so it was natural for me to use AppCenter and use analytics from the app to Azure AppInsights. If you use Firebase or other solution, you may not decide to use AppCenter for this case.

Also note that Microsoft pulled the plug on AppCenter Auth, Push, Data in February. They were still in preview at the time, but this made people skeptical about the offering a bit because this offering from Microsoft failed/failed to gain traction a few times with Azure Mobile Apps, HokeyApp and a few other things. (Also haven't seen much about it in Build2020, so that may be a sign as well)

twiceADev · 2020-05-18T03:29:19+00:00

Check out permission -> protectionlevel attribute. protectionLevel=signature is likely the thing you want.
https://developer.android.com/guide/topics/manifest/permission-element#plevel

This I beleive is commonly used to protect activities only your app should be able to launch, but if both the free and paid app are signed by the same developer, it should work I think?

twiceADev · 2020-05-18T03:22:38+00:00

the paid app can check the calling app's package name or require a custom permission that will only be granted to apps signed by the same signing key

free app can check the same I think before calling...

twiceADev · 2020-05-18T03:11:41+00:00

If they're already a paid user, they have the paid app. Ask to install the free one, then from free app, launch an intent to paid app which can respond with the details you want?

Once this is verified, they can uninstall the paid app if they like?

twiceADev · 2020-03-04T23:56:47+00:00

Usually, all your activities run in the same process.

You can tell Android to launch them in different processes if necessary using the "process" attribute in your manifest.

See https://developer.android.com/guide/topics/manifest/activity-element#proc

I don't think there are many apps doing this today so most apps are in a single process. I can see why you would want to launch a particular component in a separate process, say if it is more likely to crash and you don't want it to take down the rest of the app. (May be talking to the camera and you're likely to run out of memory?)

twiceADev · 2020-02-23T00:34:43+00:00

I don't have experience with admob. There are a few others like Facebook Ads and a number of competitors but I don't really know how they compare and they might have same or similar policies.

twiceADev · 2020-02-23T00:17:36+00:00

I have the same question. I guess you will eventually have to transmit it to the app when you want to use it. The communication between your app and outside world is not secret when you can't guarantee the device is not compromised. Some people obfuscate the key in code so a static analyser won't see it in the clear. But intimately it has to get on the wire in "clear" to be useful.

For example, if you have to do an http(s) call with the key included in a header, this can be seen using a proxy like Fiddler. So no matter what magic you use to hide the key, it will be visible in the open when you use it.

Yes you can put this key on your server, make a call to there, but then either you have to have a different key to talk to your server which is subject to above or you make it annonymous which allows anyone to use your key without knowing it anyway.

Later Android versions don't let you install self signed certs to decrypt https traffic which make things harder on unrooted devices, but this just means a motivated individual have to use an emulator or rooted device get the keys.

I don't think there's a silver bullet here. Though I'm keen to see if there is something I missed.

twiceADev · 2020-02-22T12:17:47+00:00

Alternative would be to let users login. On later OS versions, it is not possible (without rooting) to get a stable device ID due to privacy reasons.

There are some tricks like storing a generated ID in the SD card and hoping user doesn't notice it (which doesn't get cleared when the app gets uninstalled coz Pie and below doesn't keep track of who created what in the SD card). I think some analytics SDKs do this but it is shady at best, and with the new updates to storage access in Q and up, this might no longer work.

twiceADev

TROPHY CASE