Xamarin.Tips – Fixing the Highlighting Drop In Your Xamarin.Forms Projects

I’ve seen a few people run into this issue in both Visual Studio 2015 and 2017. For those of you who don’t know what I’m talking about, the issue is that code highlighting drops completely in newly opened files. I’ve personally seen it happen in both Xamarin.Forms PCLs and in Xamarin.Android projects. The reason you lose your highlighting is because the project fails to load properly, and your files will then open as “Miscellaneous Files”:

These should be opening up as part of the project and thus getting the references required for highlighting, so the goal here is to fix the project load and get these files to open as part of that project.

So here are a few steps that have worked for everyone who has reached out for help:

1. Don’t panic! This will be quick.
2. Try unloading the project and reloading it (Right click the project in the Solution Explorer > Unload Project, Right click > Reload Project)
3. Still happening when you open files in that project? Keep reading.
4. Check your Error List, there might be warnings to give you hints here.

In this post, we will look at resolving the issue for Xamarin.Forms PCL projects, and will look at fixes for Xamarin.Android projects in another article.

Xamarin.Forms PCL Issues

The most common issue here is that there is an issue in your XAML. For some reason, XAML errors/warnings can throw off the entire project load.

Here’s a quick look at what that might look like:

1. From your Error List view, find the XAML page culprit.
2. Fix the error in your XAML file.
3. Close all files in the project that is having issues.
4. In the Solution Explorer, click the refresh button at the top.
5. Re-open the files that were breaking, and you should see everything is back to normal.

Didn’t solve your problem? Let’s look at some of the conventional fixes for this then:

Refresh Your Intellisense Cache

Your Intellisense cache could be corrupt, so try clearing it. Close all your open files then:

Edit > IntelliSense > Refresh Local Cache 

Or Ctrl + Shift + R

Clearing Your Local Data

Close Visual Studio Completely, then go to %appdata%\Microsoft\VisualStudio{your_version_number}\ReflectedSchemas and delete all the content.

Reset your Visual Studio Settings

In Visual Studio, go to Tools > Import and Export Settings and hit Reset all settings.

Restart Visual Studio.

Fix All Errors and Warnings In the Error List

Similarly to how we talked about fixing your XAML error, try making sure all of your errors and warnings are fixed. Some other common issues that can cause the project to load with errors include:

1. Circular References
2. Missing project references
3. Failed nuget downloads
4. Duplicate files
5. Broken/wrong typed partial classes

 

Looking for solving this problem for your Android projects? Stay tuned for another post about some of the Android specific issues that might be causing project load fails.

 

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