Android Emulator Android Emulator Stackoverflow

You'll need to modify the Device Definitions. To do this, find the 'Device Definitions' tab in the Android Virtual Device Manager and double click on the device you're using. Make sure the Buttons are set to Hardware. Don't forget to update your device settings: Source: Stackoverflow. Price: Free / $0.99. Mupen64 is a free, open-source N64 emulator. It features decent compatibility, the basic emulator features, and more. This is the one that all the others use as a.

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This article describes the most common warning messages and issuesthat occur while configuring and running the Android Emulator. Inaddition, it describes solutions for resolving these errors as well asvarious troubleshooting tips to help you diagnose emulator problems.

Android

Deployment issues on Windows

Some error messages may be displayed by the emulator when you deployyour app. The most common errors and solutions are explained here.

Deployment errors

If you see an error about a failure to install the APK on the emulatoror a failure to run the Android Debug Bridge (adb), verify that theAndroid SDK can connect to your emulator. To verify emulatorconnectivity, use the following steps:

  1. Launch the emulator from the Android Device Manager (selectyour virtual device and click Start).

  2. Open a command prompt and go to the folder where adb isinstalled. If the Android SDK is installed at its default location,adb is located atC:Program Files (x86)Androidandroid-sdkplatform-toolsadb.exe;if not, modify this path for the location of the Android SDK on yourcomputer.

  3. Type the following command:

  4. If the emulator is accessible from the Android SDK, the emulatorshould appear in the list of attached devices. For example:

  5. If the emulator does not appear in this list, start the AndroidSDK Manager, apply all updates, then try launching theemulator again.

MMIO access error

If the message An MMIO access error has occurred is displayed,restart the emulator.

Missing Google Play Services

If the virtual device you are running in the emulator does not haveGoogle Play Services or Google Play Store installed, this condition isoften caused by creating a virtual device without including thesepackages. When you create a virtual device (seeManaging Virtual Devices with the Android Device Manager),be sure to select one or both of the following options:

  • Google APIs – includes Google Play Services in the virtual device.
  • Google Play Store – includes Google Play Store in the virtual device.

For example, this virtual device will include Google Play Services and Google Play Store:

Note

Google Play Store images are available only for some base device types suchas Pixel, Pixel 2, Nexus 5, and Nexus 5X.

Performance issues

Performance issues are typically caused by one of the following problems:

  • The emulator is running without hardware acceleration.

  • The virtual device running in the emulator is not using an x86-based system image.

The following sections cover these scenarios in more detail.

Hardware acceleration is not enabled

If hardware acceleration is not enabled, starting a virtual device fromthe Device Manager will produce a dialog with an error messageindicating that the Windows Hypervisor Platform (WHPX) is notconfigured properly:

If this error message is displayed, seeHardware acceleration issues below for steps youcan take to verify and enable hardware acceleration.

Acceleration is enabled but the emulator runs too slowly

A common cause for this problem is not using an x86-based image in yourvirtual device (AVD). When you create a virtual device (seeManaging Virtual Devices with the Android Device Manager),be sure to select an x86-based system image:

Hardware acceleration issues

Whether you are using Hyper-V or HAXM for hardware acceleration, youmay run into configuration problems or conflicts with other software onyour computer. You can verify that hardware acceleration is enabled(and which acceleration method the emulator is using) by opening acommand prompt and entering the following command:

This command assumes that the Android SDK is installed at the defaultlocation of C:Program Files (x86)Androidandroid-sdk; if not,modify the above path for the location of the Android SDK on yourcomputer.

Hardware acceleration not available

If Hyper-V is available, a message like the following example will bereturned from the emulator-check.exe accel command:

If HAXM is available, a message like the following example will bereturned:

If hardware acceleration is not available, a message like the followingexample will be displayed (the emulator looks for HAXM if it is unableto find Hyper-V):

If hardware acceleration is not available, seeAccelerating with Hyper-Vto learn how to enable hardware acceleration on your computer.

Incorrect BIOS settings

If the BIOS has not been configured properly to support hardwareacceleration, a message similar to the following example will bedisplayed when you run the emulator-check.exe accel command:

To correct this problem, reboot into your computer's BIOS and enable thefollowing options:

  • Virtualization Technology (may have a different label depending on motherboard manufacturer).
  • Hardware Enforced Data Execution Prevention.

If hardware acceleration is enabled and the BIOS is configuredproperly, the emulator should run successfully with hardware acceleration.However, problems may still result due to issues that are specific toHyper-V and HAXM, as explained next.

Hyper-V issues

In some cases, enabling both Hyper-V and Windows HypervisorPlatform in the Turn Windows features on or off dialog may notproperly enable Hyper-V. To verify that Hyper-V is enabled, use thefollowing steps:

  1. Enter powershell in the Windows search box.

  2. Right-click Windows PowerShell in the search results and selectRun as administrator.

  3. In the PowerShell console, enter the following command:

    If Hyper-V is not enabled, a message similar to the following example will bedisplayed to indicate that the state of Hyper-V is Disabled:

  4. In the PowerShell console, enter the following command:

    If the Hypervisor is not enabled, a message similar to the following example will bedisplayed to indicate that the state of HypervisorPlatform is Disabled:

If Hyper-V and/or HypervisorPlatform are not enabled, use the followingPowerShell commands to enable them:

After these commands complete, reboot.

For more information about enabling Hyper-V (including techniques forenabling Hyper-V using the Deployment Image Servicing and Managementtool), seeInstall Hyper-V.

HAXM issues

HAXM issues are often the result of conflicts with other virtualizationtechnologies, incorrect settings, or an out-of-date HAXM driver.

HAXM process is not running

If HAXM is installed, you can verify that the HAXM process is runningby opening a command prompt and entering the following command:

If the HAXM process is running, you should see output similarto the following result:

If STATE is not set to RUNNING, seeHow to Use the Intel Hardware Accelerated Execution Manager to resolve the problem.

HAXM virtualization conflicts

HAXM can conflict with other technologies that use virtualization,such as Hyper-V, Windows Device Guard, and some antivirus software:

  • Hyper-V – If you are using a version of Windows before theWindows 10 April 2018 update (build 1803) and Hyper-V is enabled,follow the steps in Disabling Hyper-V so thatHAXM can be enabled.

  • Device Guard – Device Guard and Credential Guard canprevent Hyper-V from being disabled on Windows machines. To disableDevice Guard and Credential Guard, seeDisabling Device Guard.

  • Antivirus Software – If you are running antivirus softwarethat uses hardware-assisted virtualization (such as Avast), disableor uninstall this software, reboot, and retry the Androidemulator.

Incorrect BIOS settings

If you are using HAXM on a Windows PC, HAXM will not work unlessvirtualization technology (Intel VT-x) is enabled in the BIOS. If VT-xis disabled, you will get an error similar to the following when youattempt to start the Android Emulator:

This computer meets the requirements for HAXM, but IntelVirtualization Technology (VT-x) is not turned on.

To correct this error, boot the computer into the BIOS, enable bothVT-x and SLAT (Second-Level Address Translation), then restart thecomputer back into Windows.

Disabling Hyper-V

If you are using a version of Windows before the Windows 10April 2018 Update (build 1803) and Hyper-V is enabled, you must disableHyper-V and reboot your computer to install and use HAXM. If youare using Windows 10 April 2018 Update (build 1803) or later, AndroidEmulator version 27.2.7 or later can use Hyper-V (instead of HAXM) forhardware acceleration, so it is not necessary to disable Hyper-V.

You can disable Hyper-V from the Control Panel by following thesesteps:

  1. Enter windows features in the Windowssearch box and select Turn Windows features on or off inthe search results.

  2. Uncheck Hyper-V:

  3. Restart the computer.

Alternately, you can use the following PowerShell command to disablethe Hyper-V Hypervisor:

Disable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V-Hypervisor

Intel HAXM and Microsoft Hyper-V cannot both be active at the sametime. Unfortunately, there is no way to switch between Hyper-Vand HAXM without restarting your computer.

In some cases, using the above steps will not succeed in disablingHyper-V if Device Guard and Credential Guard are enabled. If you areunable to disable Hyper-V (or it seems to be disabled but HAXMinstallation still fails), use the steps in the next section to disableDevice Guard and Credential Guard.

Disabling Device Guard

Device Guard and Credential Guard can prevent Hyper-V from beingdisabled on Windows machines. This situation is often a problem fordomain-joined machines that are configured and controlled by an owningorganization. On Windows 10, use the following steps to see if DeviceGuard is running:

  1. Enter System info in the Windows search box and selectSystem Information in the search results.

  2. In the System Summary, look to see if Device GuardVirtualization based security is present and is in the Runningstate:

If Device Guard is enabled, use the following steps to disable it:

  1. Ensure that Hyper-V is disabled (under Turn Windows Featureson or off) as described in the previous section.

  2. In the Windows Search Box, enter gpedit.msc and select the Editgroup policy search result. These steps launch the Local GroupPolicy Editor.

  3. In the Local Group Policy Editor, navigate to ComputerConfiguration > Administrative Templates > System > Device Guard:

  4. Change Turn On Virtualization Based Security to Disabled (asshown above) and exit the Local Group Policy Editor.

  5. In the Windows Search Box, enter cmd. When Command Prompt appearsin the search results, right-click Command Prompt and selectRun as Administrator.

  6. Copy and paste the following commands into the command prompt window(if drive Z: is in use, pick an unused drive letter to useinstead):

  7. Restart your computer. On the boot screen, you should see a prompt similar tothe following message:

    Do you want to disable Credential Guard?

    Press the indicated key to disable Credential Guard as prompted.

  8. After the computer reboots, check again to ensure that Hyper-V isdisabled (as described in the previous steps).

If Hyper-V is still not disabled, the policies of your domain-joinedcomputer may prevent you from disabling Device Guard or CredentialGuard. In this case, you can request an exemption from your domainadministrator to allow you to opt out of Credential Guard. Alternately,you can use a computer that is not domain-joined if you must use HAXM.

Additional troubleshooting tips

The following suggestions are often helpful in diagnosing Androidemulator issues.

Starting the emulator from the command line

If the emulator is not already running, you can start it from thecommand line (rather than from within Visual Studio) to view itsoutput. Typically, Android emulator AVD images are stored at thefollowing location (replace username with your Windows user name):

C:Usersusername.androidavd

You can launch the emulator with an AVD image from this location bypassing in the folder name of the AVD. For example, this command launchesan AVD named Pixel_API_27:

This example assumes that the Android SDK is installed at the defaultlocation of C:Program Files (x86)Androidandroid-sdk; if not,modify the above path for the location of the Android SDK on yourcomputer.

When you run this command, it will produce many lines of output whilethe emulator starts up. In particular, lines such as the followingexample will be printed if hardware acceleration is enabled and workingproperly (in this example, HAXM is used for hardware acceleration):

Viewing Device Manager logs

Often you can diagnose emulator problems by viewing the Device Managerlogs. These logs are written to the following location:

C:UsersusernameAppDataLocalXamarinLogs16.0

You can view each DeviceManager.log file by using a texteditor such as Notepad. The following example log entry indicates thatHAXM was not found on the computer:

Deployment issues on macOS

Some error messages may be displayed by the emulator when you deployyour app. The most common errors and solutions are explained below.

Deployment errors

If you see an error about a failure to install the APK on the emulatoror a failure to run the Android Debug Bridge (adb), verify that theAndroid SDK can connect to your emulator. To verify connectivity, usethe following steps:

  1. Launch the emulator from the Android Device Manager (selectyour virtual device and click Start).

  2. Open a command prompt and go to the folder where adb isinstalled. If the Android SDK is installed at its default location,adb is located at~/Library/Developer/Xamarin/android-sdk-macosx/platform-tools/adb;if not, modify this path for the location of the Android SDK on yourcomputer.

  3. Type the following command:

  4. If the emulator is accessible from the Android SDK, the emulatorshould appear in the list of attached devices. For example:

  5. If the emulator does not appear in this list, start the AndroidSDK Manager, apply all updates, then try launching theemulator again.

MMIO access error

If An MMIO access error has occurred is displayed,restart the emulator.

Missing Google Play Services

If the virtual device you are running in the emulator does not haveGoogle Play Services or Google Play Store installed, this condition isusually caused by creating a virtual device without including thesepackages. When you create a virtual device (seeManaging Virtual Devices with the Android Device Manager),be sure to select one or both of the following:

  • Google APIs – includes Google Play Services in the virtual device.
  • Google Play Store – includes Google Play Store in the virtual device.

For example, this virtual device will include Google Play Services and Google Play Store:

Note

Google Play Store images are available only for some base device types suchas Pixel, Pixel 2, Nexus 5, and Nexus 5X.

Performance issues

Performance issues are typically caused by one of the following problems:

  • The emulator is running without hardware acceleration.

  • The virtual device running in the emulator is not using an x86-based system image.

The following sections cover these scenarios in more detail.

Hardware acceleration is not enabled

If hardware acceleration is not enabled, a dialog may pop up with amessage such as device will run unaccelerated when you deploy yourapp to the Android emulator. If you are not certain whether hardwareacceleration is enabled on your computer (or you would like to knowwhich technology is providing the acceleration), seeHardware acceleration issues below for steps you cantake to verify and enable hardware acceleration.

Android emulator standalone

Acceleration is enabled but the emulator runs too slowly

A common cause for this problem is not using an x86-based image in yourvirtual device. When you create virtual device (seeManaging Virtual Devices with the Android Device Manager),be sure to select an x86-based system image:

Hardware acceleration issues

Whether you are using the Hypervisor Framework or HAXM for hardwareacceleration of the emulator, you may run into problems caused byinstallation issues or an out-of-date version of macOS. The followingsections can help you resolve this issue.

Hypervisor Framework issues

If you are using macOS 10.10 or later on a newer Mac, the Androidemulator will automatically use the Hypervisor Framework for hardwareacceleration. However, some older Macs or Macs running a version ofmacOS earlier than 10.10 may not provide Hypervisor Framework support.

To determine whether or not your Mac supports the Hypervisor Framework,open a Terminal and enter the following command:

If your Mac supports the Hypervisor Framework, the above command willreturn the following result:

If the Hypervisor Framework is not available on your Mac, you canfollow the steps in Accelerating with HAXMto use HAXM for acceleration instead.

HAXM issues

If the Android Emulator does not start properly, this problem is oftencaused by problems with HAXM. HAXM issues are often the result ofconflicts with other virtualization technologies, incorrect settings,or an out-of-date HAXM driver. Try reinstalling the HAXM driver, usingthe steps detailed inInstalling HAXM.

Additional troubleshooting tips

The following suggestions are often helpful in diagnosing Androidemulator issues.

Starting the emulator from the command line

If the emulator is not already running, you can start it from thecommand line (rather than from within Visual Studio for Mac) to viewits output. Typically, Android emulator AVD images are stored at thefollowing location:

~/.android/avd

You can launch the emulator with an AVD image from this location bypassing in the folder name of the AVD. For example, this commandlaunches an AVD named Pixel_2_API_28:

If the Android SDK is installed at its default location, the emulatoris located in the~/Library/Developer/Xamarin/android-sdk-macosx/emulator directory;if not, modify this path for the location of the Android SDK on yourMac.

When you run this command, it will produce many lines of output whilethe emulator starts up. In particular, lines such as the followingexample will be printed if hardware acceleration is enabled and workingproperly (in this example, Hypervisor Framework is used for hardwareacceleration):

Viewing Device Manager logs

Often you can diagnose emulator problems by viewing the Device Managerlogs. These logs are written to the following location:

~/Library/Logs/XamarinDeviceManager

You can view each Android Devices.log file by double-clicking it toopen it in the Console app. The following example log entry indicatesthat HAXM was not found:

Since Android 7, apps ignore user provided certificates, unless they are configured to use them.As most applications do not explicitly opt in to use user certificates, we need to place our mitmproxy CA certificate in the system certificate store,in order to avoid having to patch each application, which we want to monitor.

Please note, that apps can decide to ignore the system certificate store and maintain their own CA certificates. In this case you have to patch the application.

# 1. Prerequisites

  • Android Studio/Android Sdk is installed (tested with Version 4.1.3 for Linux 64-bit)

  • An Android Virtual Device (AVD) was created. Setup documentation available here

    • The AVD must not run a production build (these will prevent you from using adb root)
    • The proxy settings of the AVD are configured to use mitmproxy. Documentation here

  • Emulator and adb executables from Android Sdk have been added to $PATH variable

    • emulator usually located at /home/<your_user_name>/Android/Sdk/emulator/emulator on Linux systems
    • adb usually located at /home/<your_user_name>/Android/Sdk/platform-tools/adb on Linux systems
    • I added these lines to my .bashrc

  • Mitmproxy CA certificate has been created

    • Usually located in ~/.mitmproxy/mitmproxy-ca-cert.cer on Linux systems
    • If the folder is empty or does not exist, run mitmproxy in order to generate the certificates

# 2. Rename certificate

CA Certificates in Android are stored by the name of their hash, with a ‘0’ as extension (Example: c8450d0d.0). It is necessary to figure out the hash of your CA certificate and copy it to a file with this hash as filename. Otherwise Android will ignore the certificate.By default, the mitmproxy CA certificate is located in this file: ~/.mitmproxy/mitmproxy-ca-cert.cer

# Instructions

Android Emulator Android Emulator Stack Overflow Download

  • Enter your certificate folder: cd ~/.mitmproxy/
  • Generate hash and copy certificate : hashed_name=`openssl x509 -inform PEM -subject_hash_old -in mitmproxy-ca-cert.cer | head -1` && cp mitmproxy-ca-cert.cer $hashed_name.0

# 3. Insert certificate into system certificate store

Now we have to place our CA certificate inside the system certificate store located at /system/etc/security/cacerts/ in the Android filesystem. By default, the /system partition is mounted as read-only. The following steps describe how to gain write permissions on the /system partition and how to copy the certificate created in the previous step.

# Instructions for API LEVEL > 28

Starting from API LEVEL 29 (Android 10), it seems to be impossible to mount the “/” partition as read-write. Google provided a workaround for this issue using OverlayFS. Unfortunately, at the time of writing this (11. April 2021), the instructions in this workaround will result in your emulator getting stuck in a boot loop. Some smart guy on Stackoverflow found a way to get the /system directory writable anyway.

Keep in mind: You always have to start the emulator using the -writable-system option if you want to use your certificate. Otherwise Android will load a “clean” system image.

Tested on emulators running API LEVEL 29 and 30

# Instructions

  • List your AVDs: emulator -list-avds (If this yields an empty list, create a new AVD in the Android Studio AVD Manager)
  • Start the desired AVD: emulator -avd <avd_name_here> -writable-system (add -show-kernel flag for kernel logs)
  • restart adb as root: adb root
  • disable secure boot verification: adb shell avbctl disable-verification
  • reboot device: adb reboot
  • restart adb as root: adb root
  • perform remount of partitions as read-write: adb remount. (If adb tells you that you need to reboot, reboot again adb reboot and run adb remount again.)
  • push your renamed certificate from step 2: adb push <path_to_certificate> /system/etc/security/cacerts
  • set certificate permissions: adb shell chmod 664 /system/etc/security/cacerts/<name_of_pushed_certificate>
  • reboot device: adb reboot

# Instructions for API LEVEL <= 28

Android Emulator Android Emulator Stackoverflow

Android Emulator Android Emulator Stack Overflow System

Tested on emulators running API LEVEL 26, 27 and 28

Keep in mind: You always have to start the emulator using the -writable-system option if you want to use your certificate. Otherwise Android will load a “clean” system image.

Android Emulator Android Emulator Stack Overflow Free

  • List your AVDs: emulator -list-avds (If this yields an empty list, create a new AVD in the Android Studio AVD Manager)
  • Start the desired AVD: emulator -avd <avd_name_here> -writable-system (add -show-kernel flag for kernel logs)
  • restart adb as root: adb root
  • perform remount of partitions as read-write: adb remount. (If adb tells you that you need to reboot, reboot again adb reboot and run adb remount again.)
  • push your renamed certificate from step 2: adb push <path_to_certificate> /system/etc/security/cacerts
  • set certificate permissions: adb shell chmod 664 /system/etc/security/cacerts/<name_of_pushed_certificate>
  • reboot device: adb reboot

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