This guide applies to Visual Studio 2019, Visual Studio 2017, and Visual Studio for Mac. The Xamarin Android SDK Manager (installed as part of the Mobile development with.NET workload) helps you download the latest Android components that you need for developing your Xamarin.Android app. Android Studio 2.2 and higher support building C/C components of your Android project with two new options: CMake and ndk-build.Using Android Studio, you can edit and debug your native code while still using either external build system to compile and link the C/C sources. For more information, learn how to Add C and C Code to Your Project using Android Studio.
- Ndk Build Android Studio For Mac Pc
- Ndk Build Android Studio For Mac Free
- Android Studio Ndk
- Android Ndk Build
Google is committed to advancing racial equity for Black communities. See how.
Set up your development environment
- Install Android Studioversion 3.1 or higher with Android SDK Platform version 7.0 (API level 24)or higher.
- Prepare Android Studio for native development by installing Android NativeDevelopment Kit (NDK) and CMake with the SDK Manager. For more information, seeGetting Started with the NDK.
- You will need to get the ARCore SDK for Android. You can either:
- Download the ARCore SDK for Android andextract it.-or-
- Clone the repository with the following command: Phstat for excel 2016 mac free download.
Prepare your device or emulator
You can run AR apps on a supported device orin the Android Emulator:
- In the emulator, you must sign into the Google Play Store orupdate Google Play Services for AR manually.
Open the sample project
In Android Studio, open the hello_ar_c sample project in
<ARCore SDK Folder>/samples/hello_ar_c
.The sample project has build dependencies on certain versions of software, suchas Gradle and the Android SDK. If the required dependencies are not installed,Android Studio will ask you for permission to download and install them on yourmachine.
Run the sample
Make sure your Android device is connected to the development machine and clickRun in Android Studio. Then, choose your deviceas the deployment target and click OK.
Android Studio builds your project into a debuggable APK, installs the APK, andthen runs the app on your device. For more information, seeBuild and Run Your App.
As you move your device, the app automatically detects flat surfaces and draws adiamond grid. Tap the grid to place an Android robot on the surface.
Use Instant Placement
The Instant Placement API allows the user to place an AR object on the screenwithout having to wait for ARCore to detect surface geometry. Object placementis refined in real time as the user moves further around the environment. OnceARCore detects the correct pose in the region where the AR object is placed, theobject automatically updates to be pose-accurate. The user will see theholographic object become opaque.
Enable and place a virtual object using Instant Placement
To enable Instant Placement in hello_ar_c, run the app. Tap the gear icon onthe screen and choose Instant Placement from the drop-down menu. SelectEnable Instant Placement.
Tap on the screen to place an object. Make sure to continue moving the devicearound after seeing the holographic object appear on screen, so that ARCore canget sufficient data about your surroundings to accurately anchor the virtualobject.
Next steps
- Learn how to Enable ARCore in your app.
- Use Augmented Images to build apps that canrespond to 2D images, such as posters or logos, in the user's environment.
- Use Cloud Anchors
- Use the Depth API to ensure accurate depthfor realistic and immersive user experiences.
- Use Instant Placement to quicklyplace AR objects on the screen.
- Review Runtime Considerations.
- Review Design Guidelines.
System requirements| What's new| Blogs| Open source
Installing
- Visual Studio 2019 version 16.1 — Visual Studio Installer
- Visual Studio 2019 for Mac — Visual Studio 2019 for Macwith the Stableupdater channel
What's new in Xamarin.Android 9.3
Xamarin.Android 9.3 releases
- June 25, 2019 — Xamarin.Android 9.3.0.23in Visual Studio 2019 version 16.1.4.
- June 20, 2019 — Xamarin.Android 9.3.0.23in Visual Studio 2019 for Mac with the Stable updater channel.
- June 13, 2019 — Xamarin.Android 9.3.0.22in Visual Studio 2019 for Mac with the Stable updater channel
- June 4, 2019 — Xamarin.Android 9.3.0.22in Visual Studio 2019 for Mac with the Preview updater channel
- May 21, 2019 — Xamarin.Android 9.3.0.22in Visual Studio 2019 version 16.1
Corresponding Visual Studio 2019 release notes
June 20, 2019 — Xamarin.Android 9.3.0.23
Ndk Build Android Studio For Mac Pc
This version is included in the Visual Studio 2019 version 16.1.4 release andin the Stable updater channel of Visual Studio 2019 for Mac.
Issues fixed in Xamarin.Android 9.3.0.23
Application Mono Framework behavior on device and emulator
This version of Xamarin.Android updates theMono 5.18runtime and class libraries fromCommit 3cb36842toCommit 3a07bd42,adding9 new commits.
Ndk Build Android Studio For Mac Free
Changes relevant to Xamarin.Android:
- GitHub 3112,Mono GitHub 14170:'Fatal signal 11 (SIGSEGV), code 1 (SEGV_MAPERR)' native fault during C#exception handling in 64-bit arm64-v8a applications.
- Mono GitHub PR 14346:'error XA2006: Could not resolve reference to'System.Buffers.StandardFormat' (defined in assembly'Microsoft.Extensions.Configuration.Json ..' when attempting to buildXamarin.Android projects in the Release configuration, for projects thatused certain NuGet packages, such as the Microsoft.Extensions.Http.Pollyversion 3.0.0 preview. Xamarin.Android 9.3.0.23 now includes this type, sothe Android Options > Linking setting that is used by default in theRelease configuration will now be able to resolve the reference successfullyduring the build.
- Mono GitHub PR 14392:In certain debugging scenarios, the debugger could get stuck due when tryingto suspend the running process.
Android Studio Ndk
May 21, 2019 — Xamarin.Android 9.3.0.22
This version is included in the Visual Studio 2019 version 16.1 release and inthe Stable updater channel of Visual Studio 2019 for Mac.
Summary of what's new in Xamarin.Android 9.3.0.22
Build and deployment performance
- GitHub PR 2554:Skip the
_SetLatestTargetFrameworkVersionForPackageReference
MSBuildduring NuGet restore unless$(AndroidUseLatestPlatformSdk)
istrue
.This saved roughly 600 milliseconds for NuGet restore on a test project thatused an explicit$(TargetFrameworkVersion)
with$(AndroidUseLatestPlatformSdk)
set tofalse
. - GitHub PR 2561:Remove the old
_RegisterAndroidFilesWithFileWrites
target that is nolonger needed. This trimmed about 80 milliseconds off the build time of atest project. - Java.Interop GitHub PR 405,GitHub PR 2576:Change some LINQ expressions to loops and remove some redundant assemblymetadata retrieval steps. This reduced the time for the
GenerateJavaStubs
task in a test project from approximately 1414 milliseconds to 1355milliseconds. - GitHub PR 2589:Change a few uses of temporary on-disk files to work all in memory instead.
- GitHub PR 2612:Switch the
ResolveAssemblies
task to use System.Reflection.Metadatainstead of Mono.Cecil. This reduced the time for theResolveAssemblies
task in a test project from about 320 milliseconds to about 110milliseconds. - GitHub PR 2624:Switch the
GetAdditionalResourcesFromAssemblies
task to useSystem.Reflection.Metadata instead of Mono.Cecil. This reduced the time fortheGetAdditionalResourcesFromAssemblies
task in a test project from about100 milliseconds to about 50 milliseconds. - GitHub PR 2626:Exclude the
Build
target from being a dependency of theSignAndroidPackage
when building inside the IDE. This reduced the time tore-launch an unchanged test application from roughly 6.5 seconds to roughly4.5 seconds. - GitHub PR 2643:Skip over .NET Standard (and Portable Class Library) projects in the
GenerateJavaStubs
task because those project types never need to interactwith Java. This reduced the total time for theGenerateJavaStubs
taskfrom about 1 second to 870 milliseconds for incremental builds of a testXamarin.Forms project. Projects that use more .NET Standard libraries couldsee a more noticeable time savings.
App startup performance
Java.Interop GitHub PR 416,GitHub PR 2716:Change the JNI runtime interop initialization to happen lazily, allowing the appto skip some parts during startup. This reduced the time for thisinitialization step from roughly 225 milliseconds to 216 milliseconds for a testapplication on a Pixel 2 XL device.
Android NDK r19 compatibility
Xamarin.Android version 9.3 adds compatibility for running
clang
rather thangcc
for the Bundle assemblies into native code and AOT Compilationbuild options. This allows Xamarin.Android to use Android NDK version r18 andabove, where GCC has been removed.The native libraries that are part of Xamarin.Android are now also built againstAndroid NDK r19. The updated Android NDK toolchain means that it is nowrecommended to use Xamarin.Android apps only with devices running Android 4.1(API level 16) or higher. Warning XA4216 has been updated accordingly to helphighlight this change for any projects that might still have an older versionset for the
minSdkVersion
in the AndroidManifest.xml file.Android Ndk Build
Easier way to use android:extractNativeLibs='false'
Xamarin.Android 9.2 added support for the
android:extractNativeLibs='false'
setting, but enabling it required severalmanual steps. Xamarin.Android 9.3, makes this feature easier to work with bytrimming down the number of steps to just one:- Add the
android:extractNativeLibs='false'
attribute to the<application/>
element in the PropertiesAndroidManifest.xml file
arm64-v8a architecture enabled by default
Starting August 1, 2019, Google Play will require all new apps and app updatesthat include native code to provide 64-bit versions in addition to 32-bitversions. To align with this upcoming requirement,Xamarin.Android version 9.3 now includes both armeabi-v7a and arm64-v8a in thedefault value of the
$(AndroidSupportedAbis)
MSBuild property. This changewill only affect existing build configurations if the property is blank for thatconfiguration in the .csproj file. The change will not affect buildcustomized configurations where the property already includes an architectureother than armeabi-v7a.R8 version update to 1.3.52
The version of the R8 code shrinker includedin Xamarin.Android has been updated from 1.2.52 to 1.3.52.
Mono.Data.Sqlite SQLite version update
The version of SQLite used by Mono.Data.Sqlite in Xamarin.Android has beenupdated from 3.26.0 to 3.27.1,bringing in several improvements and bug fixes.
OpenTK version 0.9.9.3 warning
As mentioned in the previous release notes, the assembly for OpenTKversion 0.9.9.3 will be removed from Xamarin.Android in an upcoming release. Tohelp prepare for this removal, Xamarin.Android 9.3 now provides a build warningfor any project referencing OpenTK version 0.9.9.3:
warning XA1009: OpenTK 0.9.3 is Obsolete. Please upgrade to OpenTK 1.0
To resolve this warning in Visual Studio, ensure the selected reference forOpenTK is:
And in Visual Studio for Mac, ensure the selected reference is:
Issues fixed
![Build Build](https://blog.spreendigital.de/wp-content/uploads/2020/05/android15-477x700.png)
Application and library build process
- Developer Community 330758:Projects that had indirect dependencies on version 4.3.0 of theSystem.Runtime.Loader NuGet package would fail to build with 'XA0009: Errorwhile loading assembly .. BadImageFormatException'. Xamarin.Android 9.3allows these projects to build without error. As a caution, the
System.Runtime.Loader.AssemblyLoadContext
class in Xamarin.Androidcurrently only provides empty implementations, so although certain APIs fromNuGet packages that depend on the System.Runtime.Loader NuGet package willwork already, features that specifically depend onAssemblyLoadContext
will encounterNotImplementedException
errors. - Developer Community 346386:Attempting to cancel a build during the AOT Compilation step would onlystop the build after the AOT step completed. In Xamarin.Android 9.3,canceling the build during the AOT step now aborts the step as expected.
- Developer Community 514955:Starting in Visual Studio 2019 for Mac, the References list in theSolution pad and the Edit References window showed error icons andmissing entries for most of the base class libraries in Xamarin.Androidprojects.
- GitHub 1768:The build process did not yet provide warnings to guide projects toward therecommended best practice of keeping
minSdkVersion
less than or equal totargetSdkVersion
andtargetSdkVersion
equal tocompileSdkVersion
. - GitHub PR 2349:The build warnings and errors related to duplicate managed type names andJava type names for custom subclasses of
Java.Lang.Object
did not yetprovide all of the available information about the conflicts. - GitHub PR 2529:Under certain conditions builds would sometimes generate a new updated APKbut then incorrectly skip over the step of copying it to the final outputdirectory.
- GitHub PR 2678:Updating NuGet packages could lead to AAPT errors and Java compilationerrors if the project was not explicitly cleaned after the package update.This scenario now works as expected for an incremental build, with no needto clean the project after the package update.
- GitHub PR 2736:The
<uses-library/>
element in the AndroidManifest.xml file did notautomatically add the library for consideration by ProGuard and R8. - GitHub PR 2760:F# Xamarin.Android projects were not yet compatible with the new installpaths for F# 4.5.
- GitHub PR 2771:Projects configured to use AAPT2 could encounter
DirectoryNotFoundException
build errors if a referenced library includedan empty Android resources directory. - GitHub PR 2781:The new D8 DEX compiler option introduced in Xamarin.Android 9.2 wasnot yet compatible with the new enhanced fast deploymentmode.
- GitHub PR 2821:Updating libraries such as Xamarin.Android.Support.Annotations to newversions that used different embedded .jar files could lead to Javacompilation errors if the obj directory was not manually cleaned beforethe next build.
- GitHub PR 2880:Projects configured to use AAPT could encounter 'resource directory .. doesnot exist' build errors if a referenced library included an empty Androidresources directory.
- GitHub PR 2882:The
CompileToDalvik
task could fail with a 'no classes!' error whenattempting to deploy a project that included a .jar file with no archived.class files in it. - GitHub PR 2883:Projects configured to use AAPT2 could sometimes fail to build with 'One ormore errors occurred' messages during the
Aapt2Compile
task, depending onthe timing of the build. - GitHub PR 2914:Projects configured to use AAPT2 could sometimes fail to build with 'Valuecannot be null' messages during the
Aapt2Link
task, depending on thetiming of the build. - Starting in Xamarin.Android 9.2, the default fast deployment setting wascreating additional directories that were not needed, costing roughly anadditional 120 milliseconds on each deployment. Those additionaldirectories are only applicable for the new enhanced fast deploymentmode, so the directory creation step isnow skipped for the old default assemblies-only fast deployment mode.
Application behavior on device and emulator
- GitHub 2501:Custom subclasses of
Android.View.View
in Android XML layout files caused'Error inflating class' exceptions when running on device or emulator forprojects configured to use AAPT2. - GitHub 2684:Xamarin.Android apps built with the new R8 code shrinker enabled wouldhit an exception during startup on devices running Android versions earlierthan 8.0 Oreo (API level 26). Depending on how the application waslaunched, the app could get stuck in an error loop where the first layoutwould never appear.
- GitHub 2696:The new enhanced fast deployment modecould lead to unexpected exits on a native signal fault under certainconditions.
- GitHub 2931:Applications could exit due to unhandled exceptions similar to 'Errorinflating class android.support.v7.widget.ActionBarOverlayLayout' inprojects configured to use the new R8 code shrinker. The updated R8version 1.3.52 in Xamarin.Android 9.3 resolvesthis issue.
- GitHub PR 3009:Apps built with multidex and either the ProGuard or R8 code shrinker enabledcould fail during startup with 'java.lang.ClassNotFoundException: Didn'tfind class 'android.support.multidex.MultiDexApplication' unless a rule wasexplicitly added to the ProGuard configuration file to preserve the class.Xamarin.Android 9.3 now includes an appropriate ProGuard configuration ruleby default, so the rule no longer needs to be added by hand.
Application Mono Framework behavior on device and emulator
This version of Xamarin.Android updates theMono 5.18runtime and class libraries fromCommit 5ac37ccd,toCommit 3cb36842adding38 new commits and 4 previously backported commits. Internet explorer for mac air.
Changes relevant to Xamarin.Android:
- Developer Community 522232,Mono GitHub 12307,GitHub 2521:Apps built with both AOT Compilation and Use LLVM OptimizingCompiler enabled would exit unexpectedly during startup when targeting32-bit architectures due to a 'Fatal signal 11 (SIGSEGV)' in
Android.Runtime.AndroidTypeManager.RegisterNativeMembers()
. - Mono GitHub PR 12588:Starting with Xamarin.Android 9.2, the internal Mono runtime functions thatare used to log error messages for unexpected assembly load failures hadsome additional, unnecessary overhead.
- Mono GitHub 12843:The Debugger agent thread could abort unexpectedly on a 'Fatal signal 11(SIGSEGV), code 1' when the soft debugger was instructed to step into orstep over code in certain conditions for multithreaded applications.
- Mono GitHub 13452:Some memory operations could in theory abort unexpectedly on a SIGSEGV onx86_64 devices or emulators.
- Mono GitHub PR 13532:Concurrent request completions on an
HttpRequestChannel
could cause anuncatchable 'System.ArgumentOutOfRangeException: Index was out of range'error.
Design-time build process
- GitHub PR 2787:The
_BuildAdditionalResourcesCache
MSBuild target was being skipped duringdesign-time builds, preventing the Android designer from showingIntelliSense for some dependencies unless the user performed a full build.
Known issues
- Mono GitHub 14170:Starting in Xamarin.Android 9.3, when the debugger is attached on arm64-v8adevices, applications that hit an unhandled exception can exit on a 'Fatalsignal 11 (SIGSEGV), code 1 (SEGV_MAPERR)' if the user continues through theunhandled exception in the debugger.
Feedback
Your feedback is important to us. If there are any problems with this release, check ourGitHub Issues,Xamarin.Android Community Forums andVisual Studio Developer Communityfor existing issues. For new issues within the Xamarin.Android SDK, please report aGitHub Issue.For general Xamarin.Android experience issues, let us know via theReport a Problemoption found in your favorite IDE under Help > Report a Problem.
Contributors
A big Thank You! to contributors who made improvements in this release:
- Morten Nielsen:Skip the XA0113 compiler warning for Android library projects. The warningis only strictly relevant to Android application projects, and some libraryauthors might wish to keep using an older
$(TargetFrameworkVersion)
ifthey have users who are still on older$(TargetFrameworkVersion)
s for appsthat aren't published on Google Play.GitHub PR 2754 - vperus:Correct several links in the xamarin-android contributor documentation.GitHub PR 2748
OSS core
Xamarin.Android 9.3 is based on the open-source Xamarin.Android repositories:
- Core JNI interaction logic is in the Java.Interop repo.
- Android bindings and MSBuild tooling are in the xamarin-android repo.
- Chat is in the
xamarin/xamarin-android
Gitter channel.