Granted, I sometimes clearly miss the obvious and that might be what's going on here, so my apologies ahead of time.
I'm trying to get the Tagit tutorial going and I might be missing some supplemental document or project, but the tutorial doesn't it make it clear as to exactly what's needed to do the necessary steps. For instance, it notes "Once the project is created, adding a "Getting Started" component is as simple as adding a page, adding a reference to the appropriate Telerik namespace, dropping in a SlideView control, and connecting it to the view-model:". However, I'm not quite sure what type of View needs to be added (I was assuming a ContentView), to which project (I'm assuming the Portable project), and what viewmodel (I don't see any viewmodels)? When I tried adding a ContentView and inserted the SlideView sample code into the content area, I cannot compile as I get a number of errors including errors with "gs" files.
Once I get past this steps, will the future steps have the same perception of generality of directions?
What would be great is if I could download the completed project and that might give me some much needed hints as to what I'm missing, but if I want to do it entirely myself then it seems the tutorial is missing some other references.
For the record, I've always been extremely satisfied with the professionalism and help that the Telerik team has offered. I don't have any doubts that I'll be able to eventually get this going.
My system: I'm on Windows 10 (version 1803...and, no, I cannot upgrade to 1903 due to corporate standardization); Visual Studio 2019 (version 16.2.0), and I've updated Xamarin.Forms to 4.2.0.618605-pre2.
11 Answers, 1 is accepted
Rank 2
Correct, the best place to start is from the Source Code for the demo. The tutorial expects that you've already had a chance to review the demo code and are familiarized with the layout.
Then, when you read steps explained like "Add a TreeView to a page and add a collection to the view model", it's not a reconstruction explanation of the entire demo, but rather to build the understanding of why that demo was built that way.
To keep things clear and concise, we try to stick to the scope of the Telerik component's responsibility, rather than a general Xamarin.Forms development tutorial. The only time we venture into unrelated development is if the context is about a featured external service (i.e. Azure Cognitive Services).
Before I close, I wanted to touch on your comments about your environment:
- Windows 10 1803 is fine. The min UWP SDK you want is 16299 (because of .NET Standard 2.0 requirement of Xamarin.Forms)
- Xamarin.Forms 4 or later is not officially supported yet. It should work fine, but if there is un-explainable behavior, try using 3.6 (this is what we built the latest version of UI for Xamarin with).
- VS2019 16.2 is perfect! This gives you the best chance at a smoothly working Xamarin dev environment. Microsoft has put a lot of working into making Xamarin as seamless as possible (e.g. Remoted iOS Simulator, default Android SDKs, etc).
If you have any trouble, please don't hesitate to open a Support Ticket and share the specifics of the problem so we can dig deeper.
Regards,
Lance | Technical Support Engineer, Principal
Progress Telerik
Rank 2
Thank you for the updated steps.
A couple of things, plus an issue we still have with trying to compile.
- The first issue we found was that the *.csproj files assumed we had R3 2017, but we just downloaded R2 2019 so I manually changed all those in the (4) project files.
- FFImageLoading could not be found; version 2.2.20 upgraded to 2.4.11
But here's the error that we're getting that I'm not sure how to overcome:
Error CS0012 The type 'DateTime' is defined in an assembly that is not referenced. You must add a reference to assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. (in tagit\Models\ImageCreationEvent.cs line 11)
It doesn't make any sense. I tried doing a clean rebuild and removed the bin/obj directories first, to no avail (and tried someone's suggestion to add a reference to netstandard to the csproj file, but this just caused other errors). I tried to see if I could upgrade the tagit portable project to 4.6.1, but it wouldn't let me without opt-into NuGet 3.0 support and reload all packages, so I decided to pass on trying that out.
Any ideas what might be going on?
Finally, once we get that working, it looks like the Android solution will have it's own issues: Invalid value 'armeabi' in $(AndroidSupportedAbis). This ABI is no longer supported. Please update your project properties. tagit.Android"
Thanks!
That error is misleading and a left-over from MSBuild and .NETFramework error messages. You don't "add a reference" to .NET Standard. The project is a .NEtStandard project or it's not. I have a feeling you might be using an old version of the demo.
Can you confirm that you're using the TagIt project from this repository: https://github.com/telerik/telerik-xamarin-forms-samples? I've double checked that it is up to date and builds cleanly using the latest version of Telerik UI for Xamarin.
To be clear, you should not have had to change the Visual Studio version or do anything, it will build the first time. To double check, I just forked the repo a few minutes ago (here is my fork) and it builds successfully the first time in Visual Studio 2019 (16.2).
Here's a screenshot:
Android ABI
The reason you're seeing the "unsupported ABI" is probably because you updated the target Android SDK to 28.0.0.1. You need to remove the deprecated ABI (an ABI is the architecture type that will be packaged for the google Play Store).
You can usually find quick answers for such errors by searching the entire text of the message preceded by "Xamarin". In this case, you would find this StackOverflow answer when searching for "xamarin Invalid value 'armeabi' in $(AndroidSupportedAbis). This ABI is no longer supported.".
The quickest way to remove that ABI is to just uncheck it in the Android project settings. Here's a screenshot:
Circling back to what I mentioned above, I suspect you might be using an old version of the project. The latest one is up to date with Android 9 standards (we enable Multi-Dex, removed the armeabi-v7a and set the Max Java Heap to 1G).
I recommend deleting whatever source you have locally, and clone the master branch of the repo (mine or the official) and use that moving forward.
Regards,
Lance | Technical Support Engineer, Principal
Progress Telerik
Rank 2
Definitely helpful! I didn't realize the tutorial site was pointing to old code.
I can "almost" get it to compile (lol)! the Telerik NuGet source doesn't list anything for a Xamarin Trial package just a package called "Telerik.UI.for.Xamarin.Primitives.Lite". We're using "https://nuget.telerik.com/nuget" for the NuGet source. What am I missing here?
Thank you for letting me know that the tutorial's download is outdated. I'll have the admins take care of that ASAP. Ultimately, there should not be any references to a Lite package, only Telerik.UI.for.Xamarin.Trial.
If you're still using the old version, you should definitely update now. I was one of the developers who modernized the TagIt app and backend. There were a lot of changes and it will be an uphill battle to get the old version working correctly with newer Xamarin.Forms and FFImageLoading and Xamarin.Forms 3.x and later. I had to completely remove the PCL project and build the .NETStandard 2 project in its place.
Before I close, I noticed that your account does not have any recent licenses associated with it. are you using another account to restore the packages? Otherwise, you won'tbe able to restore the Telerik.UI.for.Xamarin.Trial package in the project.
Ask the license holder to assign you as a Licensed User. It literally takes 20 seconds to transfer the license to you to use (the owner will remain the owner). That way you can get access to all the packages on the Telerik NuGet server.
After you get the license assigned to you, you can change the nuget package from Telerik.UI.for.Xamarin.Trial to Telerik.UI.for.Xamarin.
Bonus: you will be able to open Support Tickets as well. Although I've been able to get to your forum posts quickly, this is not always the case. Whereas a Support Ticket always gets a < 24 hour response.
Regards,
Lance | Technical Support Engineer, Principal
Progress Telerik
I want to apologize for any inconvenience that has caused. I have confirmed that the download button on the TagIt tutorial is most definitely the wrong one. It is the old PCL project.
At this point, I want to double down on my previous suggestion that you should delete the old project and use the new version. For your convenience, I have zipped up the new version that I just compiled with VS2019 so that you do not have to clone the repo.
Find that attached.
Regards,
Lance | Technical Support Engineer, Principal
Progress Telerik
Rank 2
Even when you're logged into a licensed user, it will not show the Trial packages. That is because a Trial license is a special one-day agreement for a particular version. The account you're using right now doesn't have a Xamarin license, only a UI for WPF and UI for Blazor (and you're a Licensed User for another UI for WPF license).
I have two options for you to move forward:
1. Start a new trial
2. Login with an account that has a UI for Xamarin license.
Option 1. Starting a New Trial
What you could do it try to start a new UI for Xamarin trial. Take the following steps:
1. Go to https://www.telerik.com/xamarin-ui
2. Click "Download trial"
This will assign you a trial license for the current release (the same one the TagIt demo is using). The Telerik NuGet server will start showing the trial package when it syncs with the license server in about 5-15 minutes.
Once the the trial license is on your account and the NuGet server has synced, this is what it should look like in the NuGet Package manager:
If you have trouble with the NuGet server not providing the .Trial NuGet package, you could download the nupkg file from the My Downloads - Xamarin. page and host it in another place.
For example, if you have an Azure DevOps, you could put it in a Azure Artifacts feed like I show in the blog post I wrote this week: https://www.telerik.com/blogs/azure-devops-and-telerik-nuget-packages
Option 2. Use the Licensed Version
I do not recommend installing that if you already have a license for UI for Xamarin with another account. This will only complicate things. Instead you can download the licensed installer from here: My Downloads - Xamarin.
If you do have credentials for an account that does have a UI for Xamarin License. I would uninstall the Trial NuGet package and install the licensed one instead. I have updated the demo so that it uses the non-trial packages instead.
Regards,
Lance | Technical Support Engineer, Principal
Progress Telerik
Rank 2
That did it! It runs now! THANK YOU!
I did download the trial yesterday, but I wonder if I did it under the wrong account context or none at all?
Okay, now I can have fun with looking into the code and the tutorial and finding other (dumb) things that will stymie me! LOL
Excellent! I can also confirm you now have a trial Support license as well. This give you access to the Xamarin support system during your trial and speak with the developers and engineers like myself on a faster and private basis.
If you have any further trouble, please open a Support Ticket here so that we can assist further. I see you've submitted tickets before, so I'm guessing you're familiar with the ticketing system. However, f you have any questions about how to open tickets, just let me know.
Before I close this out, I don't remember exact if the tutorial shows you where to put your Azure service keys. We created a static class that holds these values and you should just be able to enter yours and recompile
Here's a screenshot of that static class:
As to where you get this key, it's in your Azure portal and under the Cognitive service you created. For example, here is one of mine:
If you have any trouble setting up your services, open a ticket and I'll walk you through it.
Regards,
Lance | Technical Support Engineer, Principal
Progress Telerik