project.clj options

This page contains a detailed description of all project.clj options that are used by lein-droid.

A default project.clj file that gets created with lein droid new ... command has most of the necessary options defined, so the most of the time you won’t have to change lein-droid related attributes much.

You can also reference a sample file which contains example uses of different lein-droid options.

:android

This is where main and most relevant configuration options are. This option should itself be a map, which contents are described below.

:aot

This is similar to Leiningen’s own :aot option. This could either be:

• a list of namespaces to be AOT-compiled;
• :all to AOT-compile all used namespaces;
• :all-with-unused to AOT-compile all namespaces.

:all-with-unused is usually used with :dev profile because you want to have the complete libraries available while you are developing. For :release profile it is better to use :all value because it compiles only those namespaces that are necessary.

:aot-exclude-ns

This should be a list of namespaces not to be AOT-compiled. Most of the time this lists consists of Clojure’s own namespaces that use JVM-specific classes. As of Clojure 1.5, excluded namespaces are clojure.parallel and clojure.core.reducers.

:assets-path

The path to the directory which contains assets for your application. By default its value is "./assets".

:dex-opts

With this option you can pass additional arguments to dx executable. We usually use it to give more memory to dx and force use of multiple cores when building large projects like this: ["-JXmx4096M" "--num-threads=2"].

:enable-dynamic-compilation

By default, :dev profile has this option enabled and in :release it is disabled. You can set this option to true in :release profile if you use dynamic compilation as your application’s feature (and not just for REPL development).

:external-classes-paths

This options is a list of directories with classfiles, and JARs that you want to include in your classpath. Use this only for libraries that aren’t available in Maven repositories and Clojars since it makes your project build environment-dependent.

:external-res-paths

Directories in which to find additional resources.

:force-dex-optimize

If you still get errors during DEXing, even with :dex-opts changed liberally, you can set this option to true. This will result in slower DEXing during debug builds but may resolve the issue.

:ignore-log-priority

Setting this parameter to a vector of logging priorities will force the respective logging methods from neko.log namespace to be completely ignored in the build. You can use this parameter, for example, to elide all neko.log/d calls from the release build in compile time.

Available priorities: :verbose, :debug, :info, :warning, :error.

:key-alias

This option should be an alias of your key inside :keystore-path.

You should set this option only for the :release profile, since :dev profile uses special debug key for signing applications.

It is better to set this option in ~/.lein/profiles.clj for better repeatability.

:keypass

This options can contain a password to your key in the private keystore. It is not advised to use this option.

If not set, you will be asked for the password during release build which is a more secure method.

If you still decide to use this option, specify it in ~/.lein/profiles.clj to avoid exposing your password.

:keystore-path

This options should point at a keystore file for signing your release builds. Please consult this guide for more information on keys and application signing.

You should set this option only for the :release profile, since :dev profile uses special debug key for signing applications.

It is better to set this option in ~/.lein/profiles.clj for better repeatability.

:library

This option should be set to true if you are developing a Clojure/Android library that relies on Android SDK to be compiled and built..

:native-libraries-paths

A list of native libraries to include into your application.

:project-dependencies

This should contain a list of paths to project you want to use as dependencies.

Dependency projects are used for libraries which contain resources you want to use in your application, e.g. ActionBarSherlock library.

:repl-device-port

This option should be a port number that will be opened by nREPL on the Android device. By default it is set to 9999.

:repl-local-port

This option should be a port number which will be opened on your local machine to access the remote nREPL. By default it is set to 9999.

:res-path

Path to resources folder. It is usually and by default "./res" in your project root.

:resource-jars-paths

A list of JARs which contain resources you want to include into your application.

:sdk-path

Its value should be a string that specifies the path to your Android SDK. Its root path is where tools, platform-tools and other directories are.

It is a good idea to set this option in ~/.lein/profiles.clj file. This way you won’t have to copy it into every project, and it also make your project contain less environment-specific parts.

:sigalg

If your release keystore uses signing algorithm different from the default SHA1withRSA, you can specify it using this parameter. For example, if your keystore was generated using DSA, you should set this parameter to SHA1withDSA.

:start-nrepl-server

Same as :enable-dynamic-compilation, set this option to true if you want to start nREPL server even in release builds of your application. If so, don’t forget to include nrepl dependency in :release profile.

:storepass

This options can contain a password to your private keystore. It is not advised to use this option.

If not set, you will be asked for the password during release build which is a more secure method.

If you still decide to use this option, specify it in ~/.lein/profiles.clj to avoid exposing your password.

:support-libraries

Its value should be a vector of strings which describe support libraries’ versions that should be included into your project. Currently there are five support libraries:

• v4
• v7-appcompat
• v7-gridlayout
• v7-mediarouter
• v13

N.B.: I’m not sure if v7-* libraries will work this way since they additionally have resources to be included. Most probably, to use v7 support libraries you’ll have to include them as :project-dependencies.

:target-version

This option should be a number which specifies the version of Android API you want to target. You can see the mapping between version names and API numbers here.

You can also use a keyword instead of a number for certain SDK versions. Here’s the mapping:

Keyword	Version number
:froyo	8
:gingerbread	10
:honeycomb	13
:ics	15
:jelly-bean	17

:use-google-api

Set this option to true if you intend to use additional Google APIs like Maps or Google Play Services.

:dependencies

This options is the same like in every other project.clj, it should contain a vector of dependency definitions. If you want to include resources from certain dependency, add :use-resources true to the definition vector, like this:

:dependencies [[org.clojure-android/clojure "1.5.1-SNAPSHOT" :use-resources true]
               ...]

There are two main dependencies that are crucial for Clojure/Android development (you can get a working setup without them, but it won’t be much fun). First is org.clojure-android/clojure, which is a special Clojure build that enables dynamic compilation on Android. Apart from that there are no other changes, so consider which version to use the same as you do it for regular Clojure. Most of the time the latest version will do:

Neko is a primary library for CoA development. It initializes dynamic compilation and provides with various utilities for creating UI and using Android API. You can get Neko from Clojars as well:

Other dependencies are up to you, lein-droid allows you to use any conventional Clojure libraries in your projects as long as they don’t require any JVM-specific classes (like sun.* package and the like).

:global-vars

*warn-on-reflection*

This option is highly recommended to be enabled, since reflection on Android is much slower than on JVM, and most initial performance problems with Clojure/Android development come from unnoticed reflection cases. If *warn-on-reflection* is set to true, you will see them during project compilation stage.

:java-only

If this option is set to true, lein-droid will act like a common Android build tool. Use this option if for some reason you want to use lein-droid for building your regular Java/Android applications.

:profiles

There are two main profiles by default there: :dev and :release. As names suggest, the first is a profile you wanna use while developing your application. It has nrepl dependency which gives you a remote REPL to connect to. The second profile is intended to be used to build the releases of your application that will be published in any way.

Of course, you can create your custom profiles, but mind that lein-droid relies on these two, so it’s a bad idea to remove them. The lein-droid tutorial explains how to easily use these two profiles.