shell.nix

with import <nixpkgs> { config.android_sdk.accept_license = true; };

let
  inherit (pkgs) mkShell openjdk;
  androidPkgs = androidenv.composeAndroidPackages {
    platformVersions = [ "28" ];
    abiVersions = [ "x86" "x86_64"];
    includeEmulator = true;
  };
  inherit (androidPkgs) androidsdk;
in mkShell {
  JAVA_HOME = "${openjdk}";
  ANDROID_HOME = "${androidsdk}";

  buildInputs = with pkgs; [
    nodejs-10_x
    androidsdk
  ];
}

Try it like this, fixed these errors for me:

let
  androidsdk = pkgs.androidsdk_9_0.overrideAttrs (oldAttrs: {
    useGoogleAPIs = true;
    includeSystemImages = true;
    includeEmulator = true;
  });
in pkgs.mkShell {
  ANDROID_HOME = "${androidsdk}/libexec/android-sdk";
  # …
}

(nixpkgs 20.09pre218613.ae6bdcc5358)

Upon tns run android I always hit this though:

[nix-shell:/…]$ yarn run tns run android
yarn run v1.22.4
$ …/node_modules/.bin/tns run android
Searching for devices...
Preparing project...
File change detected. Starting incremental webpack compilation...
Starting type checking service...
Using 1 worker with 4096MB memory limit
…
Webpack compilation complete. Watching for file changes.
Webpack build done!
Project successfully prepared (android)
Building project...
Gradle build...
         + setting applicationId
         + applying user-defined configuration from /…/app/App_Resources/Android/app.gradle
         + using android X library androidx.legacy:legacy-support-v4:1.0.0
         + adding nativescript runtime package dependency: nativescript-optimized-with-inspector
         + adding aar plugin dependency: /…/node_modules/tns-core-modules-widgets/platforms/android/widgets-release.aar

Execution failed for task ':app:mergeDebugResources'.
error=2, No such file or directory

Unable to apply changes on device: emulator-5554. Error is: Command ./gradlew failed with exit code 1.
^C

[nix-shell:…]$

Not sure which file it is missing… I'm trying to build the Svelte Native template.

If you have new findings please let me know.

I figured it out! The easiest way to work around this problem is using buildFHSUserEnv, as documented here https://nixos.wiki/wiki/Android#gradlew