[Bug] Can't resolve type for PrismApplication in XamlC on App.xaml

BretJohnson commented 3 years ago

Description

Steps to Reproduce

Follow steps here to create a blank Prism application: https://prismlibrary.com/docs/xamarin-forms/creating-your-first-prism-app.html. I used the steps on Windows (installing the Prism templates there) and then moved the project to Mac.
Build app and try to run on Android emulator

Expected Behavior

Should build/run OK.

Actual Behavior

The App.xaml below causes issues.

<?xml version="1.0" encoding="utf-8" ?>
<prism:PrismApplication xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:prism="http://prismlibrary.com"
             x:Class="PrismBlankApp2.App">
  <Application.Resources>
    </Application.Resources>
</prism:PrismApplication>

XamlC will fail as below:

Done building project "PrismBlankApp2.csproj" -- FAILED.

Build FAILED.

App.xaml : error :  : XamlC error XFC0000 : Cannot resolve type "PrismApplication".
    0 Warning(s)
    1 Error(s)

This is the same issue discussed here: https://twitter.com/Depechie/status/1388894745716527107 And here: https://stackoverflow.com/questions/65819683/visual-studio-show-an-error-about-prismapplication If there are any workarounds, let's note them there.

Basic Information

Version with issue: 5.0
Last known good version: unknown

Environment

Show/Hide Visual Studio info

``` === Visual Studio Enterprise 2019 for Mac (Preview) === Version 8.10 Preview (8.10 build 1712) Installation UUID: 123999d3-6da7-4592-ac7f-c45b1036b947 GTK+ 2.24.23 (Raleigh theme) Xamarin.Mac 6.18.0.23 (d16-6 / 088c73638) Package version: 612000140 === Mono Framework MDK === Runtime: Mono 6.12.0.140 (2020-02/51d876a041e) (64-bit) Package version: 612000140 === Xamarin Designer === Version: 16.10.0.115 Hash: c750fbf1b Branch: remotes/origin/d16-10 Build date: 2021-05-03 09:46:50 UTC === Roslyn (Language Service) === 3.10.0-3.21226.12+c153357eb74f4b5c8fc905b7ae42168b76515531 === NuGet === Version: 5.9.0.7134 === .NET Core SDK === SDK: /usr/local/share/dotnet/sdk/5.0.202/Sdks SDK Versions: 5.0.202 5.0.201 5.0.103 3.1.408 3.1.407 3.1.406 3.1.300 3.1.201 MSBuild SDKs: /Applications/Visual Studio.app/Contents/Resources/lib/monodevelop/bin/MSBuild/Current/bin/Sdks === .NET Core Runtime === Runtime: /usr/local/share/dotnet/dotnet Runtime Versions: 5.0.5 5.0.4 5.0.3 3.1.14 3.1.13 3.1.12 3.1.4 3.1.3 === .NET Core 3.1 SDK === SDK: 3.1.408 === Xamarin.Profiler === Version: 1.6.15.68 Location: /Applications/Xamarin Profiler.app/Contents/MacOS/Xamarin Profiler === Updater === Version: 11 === Apple Developer Tools === Xcode 12.4 (17801) Build 12D4e === Xamarin.Mac === Version: 7.13.0.7 (Visual Studio Enterprise) Hash: bb4428722 Branch: d16-10 Build date: 2021-04-29 04:38:53-0400 === Xamarin.iOS === Version: 14.19.0.7 (Visual Studio Enterprise) Hash: bb4428722 Branch: d16-10 Build date: 2021-04-29 04:38:54-0400 === Xamarin.Android === Version: 11.3.0.1 (Visual Studio Enterprise) Commit: xamarin-android/d16-10/22fc2b3 Android SDK: /Users/bret/Library/Developer/Xamarin/android-sdk-macosx Supported Android versions: None installed SDK Tools Version: 26.1.1 SDK Platform Tools Version: 30.0.4 SDK Build Tools Version: 30.0.2 Build Information: Mono: b4a3858 Java.Interop: xamarin/java.interop/d16-10@f39db25 ProGuard: Guardsquare/proguard/v7.0.1@912d149 SQLite: xamarin/sqlite/3.35.4@85460d3 Xamarin.Android Tools: xamarin/xamarin-android-tools/d16-10@c5732a0 === Microsoft OpenJDK for Mobile === Java SDK: /Users/bret/Library/Developer/Xamarin/jdk/microsoft_dist_openjdk_1.8.0.25 1.8.0-25 Android Designer EPL code available here: https://github.com/xamarin/AndroidDesigner.EPL === Android SDK Manager === Version: 16.10.0.12 Hash: e240b8c Branch: remotes/origin/d16-10 Build date: 2021-04-27 00:14:36 UTC === Android Device Manager === Version: 16.10.0.14 Hash: e340248 Branch: remotes/origin/d16-10 Build date: 2021-04-27 00:14:54 UTC === Build Information === Release ID: 810001712 Git revision: f797f890aa5ab5bbb36eb1d9ec210a5c9cefdc1f Build date: 2021-05-03 13:57:28-04 Build branch: release-8.10 === Operating System === Mac OS X 10.16.0 Darwin 20.4.0 Darwin Kernel Version 20.4.0 Fri Mar 5 01:14:14 PST 2021 root:xnu-7195.101.1~3/RELEASE_X86_64 x86_64 ```

Build Logs

Screenshots

Reproduction Link

Workaround

BretJohnson commented 3 years ago

Here's a blank project I created, per the above steps (plus upgrading to Forms 5), which shows the issue. PrismBlankApp2.zip

jsuarezruiz commented 3 years ago

Could you try to use clr-namespace instead of URI for top level element?

xamarin / Xamarin.Forms