Buildozer: I am using Virtual Machine provided in the official kivy website for building android APK, this is the part of log file

[prerna-khanna]

#` Apache ANT found at /home/kivy/.buildozer/android/platform/apache-ant-1.9.4
# Android SDK found at /home/kivy/.buildozer/android/platform/android-sdk-20
# Android NDK found at /home/kivy/.buildozer/android/platform/android-ndk-r9c
# Check application requirements
# Check garden requirements
# Compile platform
# Run '/usr/bin/python -m pythonforandroid.toolchain create --dist_name=myapp --bootstrap=sdl2 --requirements=kivy,opencv --arch armeabi-v7a --copy-libs --color=always --storage-dir=/home/kivy/Desktop/Camera/.buildozer/android/platform/build'
# Cwd /home/kivy/Desktop/Camera/.buildozer/android/platform/python-for-android-new-toolchain
[INFO]:    Will compile for the following archs: armeabi-v7a
[INFO]:    Found Android API target in $ANDROIDAPI
[INFO]:    Available Android APIs are (19)
[INFO]:    Requested API target 19 is available, continuing.
[INFO]:    Found NDK dir in $ANDROIDNDK
[INFO]:    Got NDK version from $ANDROIDNDKVER
[INFO]:    Using Google NDK r9c
[INFO]:    Found virtualenv at /usr/local/bin/virtualenv
[INFO]:    ccache is missing, the build will not be optimized in the future.
[WARNING]: Could not find toolchain subdirectory!
[WARNING]: Could not find any toolchain for arm-linux-androideabi!
[WARNING]: Missing executable: autoconf is not installed
[WARNING]: Missing executable: automake is not installed
[WARNING]: Missing executable: libtoolize is not installed
[ERROR]:   python-for-android cannot continue; aborting
# Command failed: /usr/bin/python -m pythonforandroid.toolchain create --dist_name=myapp --bootstrap=sdl2 --requirements=kivy,opencv --arch armeabi-v7a --copy-libs --color=always --storage-dir=/home/kivy/Desktop/Camera/.buildozer/android/platform/build
# 

[AndreMiras]

I have never tried this VM, but it's not the first time I see it has some issue recently.
Could you please provide some of the info we need such as buildozer.spec file?
Funny it's saying the toolchain is not found, even though it's listing the NDK. It should normally be in ~/.buildozer/android/platform/android-ndk-r9c/toolchains/ and I thought this was being handled during ndk download. I'm a bit too busy recently to try the official VM. But perhaps you could give the Dockerfile a try in the meantime.

[prerna-khanna]

[app]

# (str) Title of your application
title = Camera

# (str) Package name
package.name = myapp

# (str) Package domain (needed for android/ios packaging)
package.domain = org.test

# (str) Source code where the main.py live
source.dir = .

# (list) Source files to include (let empty to include all the files)
source.include_exts = py,png,jpg,kv,atlas

# (list) List of inclusions using pattern matching
#source.include_patterns = assets/*,images/*.png

# (list) Source files to exclude (let empty to not exclude anything)
#source.exclude_exts = spec

# (list) List of directory to exclude (let empty to not exclude anything)
#source.exclude_dirs = tests, bin

# (list) List of exclusions using pattern matching
#source.exclude_patterns = license,images/*/*.jpg

# (str) Application versioning (method 1)
version = 1.0

# (str) Application versioning (method 2)
# version.regex = __version__ = ['"](.*)['"]
# version.filename = %(source.dir)s/main.py

# (list) Application requirements
# comma seperated e.g. requirements = sqlite3,kivy
requirements = kivy, opencv

# (str) Custom source folders for requirements
# Sets custom source for any requirements with recipes
# requirements.source.kivy = ../../kivy

# (list) Garden requirements
#garden_requirements =

# (str) Presplash of the application
#presplash.filename = %(source.dir)s/data/presplash.png

# (str) Icon of the application
#icon.filename = %(source.dir)s/data/icon.png

# (str) Supported orientation (one of landscape, portrait or all)
orientation = portrait

# (list) List of service to declare
#services = NAME:ENTRYPOINT_TO_PY,NAME2:ENTRYPOINT2_TO_PY

#
# OSX Specific
#

#
# author = © Copyright Info

# change the major version of python used by the app
osx.python_version = 3

# Kivy version to use
osx.kivy_version = 1.9.1

#
# Android specific
#

# (bool) Indicate if the application should be fullscreen or not
fullscreen = 0

# (string) Presplash background color (for new android toolchain)
# Supported formats are: #RRGGBB #AARRGGBB or one of the following names:
# red, blue, green, black, white, gray, cyan, magenta, yellow, lightgray,
# darkgray, grey, lightgrey, darkgrey, aqua, fuchsia, lime, maroon, navy,
# olive, purple, silver, teal.
#android.presplash_color = #FFFFFF

# (list) Permissions
#android.permissions = INTERNET

# (int) Android API to use
#android.api = 19

# (int) Minimum API required
#android.minapi = 9

# (int) Android SDK version to use
#android.sdk = 20

# (str) Android NDK version to use
#android.ndk = 9c

# (bool) Use --private data storage (True) or --dir public storage (False)
#android.private_storage = True

# (str) Android NDK directory (if empty, it will be automatically downloaded.)
#android.ndk_path =

# (str) Android SDK directory (if empty, it will be automatically downloaded.)
#android.sdk_path =

# (str) ANT directory (if empty, it will be automatically downloaded.)
#android.ant_path =

# (bool) If True, then skip trying to update the Android sdk
# This can be useful to avoid excess Internet downloads or save time
# when an update is due and you just want to test/build your package
# android.skip_update = False

# (str) Android entry point, default is ok for Kivy-based app
#android.entrypoint = org.renpy.android.PythonActivity

# (list) Pattern to whitelist for the whole project
#android.whitelist =

# (str) Path to a custom whitelist file
#android.whitelist_src =

# (str) Path to a custom blacklist file
#android.blacklist_src =

# (list) List of Java .jar files to add to the libs so that pyjnius can access
# their classes. Don't add jars that you do not need, since extra jars can slow
# down the build process. Allows wildcards matching, for example:
# OUYA-ODK/libs/*.jar
#android.add_jars = foo.jar,bar.jar,path/to/more/*.jar

# (list) List of Java files to add to the android project (can be java or a
# directory containing the files)
#android.add_src =

# (list) Android AAR archives to add (currently works only with sdl2_gradle
# bootstrap)
#android.add_aars =

# (list) Gradle dependencies to add (currently works only with sdl2_gradle
# bootstrap)
#android.gradle_dependencies =

# (str) python-for-android branch to use, defaults to stable
#p4a.branch = stable

# (str) OUYA Console category. Should be one of GAME or APP
# If you leave this blank, OUYA support will not be enabled
#android.ouya.category = GAME

# (str) Filename of OUYA Console icon. It must be a 732x412 png image.
#android.ouya.icon.filename = %(source.dir)s/data/ouya_icon.png

# (str) XML file to include as an intent filters in <activity> tag
#android.manifest.intent_filters =

# (list) Android additionnal libraries to copy into libs/armeabi
#android.add_libs_armeabi = libs/android/*.so
#android.add_libs_armeabi_v7a = libs/android-v7/*.so
#android.add_libs_x86 = libs/android-x86/*.so
#android.add_libs_mips = libs/android-mips/*.so

# (bool) Indicate whether the screen should stay on
# Don't forget to add the WAKE_LOCK permission if you set this to True
#android.wakelock = False

# (list) Android application meta-data to set (key=value format)
#android.meta_data =

# (list) Android library project to add (will be added in the
# project.properties automatically.)
#android.library_references =

# (str) Android logcat filters to use
#android.logcat_filters = *:S python:D

# (bool) Copy library instead of making a libpymodules.so
#android.copy_libs = 1

# (str) The Android arch to build for, choices: armeabi-v7a, arm64-v8a, x86
android.arch = armeabi-v7a

#
# Python for android (p4a) specific
#

# (str) python-for-android git clone directory (if empty, it will be automatically cloned from github)
#p4a.source_dir =

# (str) The directory in which python-for-android should look for your own build recipes (if any)
#p4a.local_recipes =

# (str) Filename to the hook for p4a
#p4a.hook =

# (str) Bootstrap to use for android builds
# p4a.bootstrap = sdl2


#
# iOS specific
#

# (str) Path to a custom kivy-ios folder
#ios.kivy_ios_dir = ../kivy-ios

# (str) Name of the certificate to use for signing the debug version
# Get a list of available identities: buildozer ios list_identities
#ios.codesign.debug = "iPhone Developer: <lastname> <firstname> (<hexstring>)"

# (str) Name of the certificate to use for signing the release version
#ios.codesign.release = %(ios.codesign.debug)s


[buildozer]

# (int) Log level (0 = error only, 1 = info, 2 = debug (with command output))
log_level = 2

# (int) Display warning if buildozer is run as root (0 = False, 1 = True)
warn_on_root = 1

# (str) Path to build artifact storage, absolute or relative to spec file
# build_dir = ./.buildozer

# (str) Path to build output (i.e. .apk, .ipa) storage
# bin_dir = ./bin

#    -----------------------------------------------------------------------------
#    List as sections
#
#    You can define all the "list" as [section:key].
#    Each line will be considered as a option to the list.
#    Let's take [app] / source.exclude_patterns.
#    Instead of doing:
#
#[app]
#source.exclude_patterns = license,data/audio/*.wav,data/images/original/*
#
#    This can be translated into:
#
#[app:source.exclude_patterns]
#license
#data/audio/*.wav
#data/images/original/*
#


#    -----------------------------------------------------------------------------
#    Profiles
#
#    You can extend section / key with a profile
#    For example, you want to deploy a demo version of your application without
#    HD content. You could first change the title to add "(demo)" in the name
#    and extend the excluded directories to remove the HD content.
#
#[app@demo]
#title = My Application (demo)
#
#[app:source.exclude_patterns@demo]
#images/hd/*
#
#    Then, invoke the command line with the "demo" profile:
#
#buildozer --profile demo android debug

[AndreMiras]

Why closing @prerna-khanna, did you fix your problem? Could you share your findings here?
Like I said you're not the first reporting about the official VM, so I'd like to investigate if I ever get time.

[prerna-khanna]

@AndreMiras I could not fix this problem, so I started again from scratch and this time it was resolved.
But still facing problems with openCV
https://github.com/kivy/python-for-android/issues/1313