In Android/Gradle how to define a task that only runs when building specific buildType/buildVariant/productFlavor (v0.10+)

Question

Android Plugin for Gradle generates for every BuilType/Flavor/BuildVariant a task. The problem is that this task will be generated dynamically and thus won't be available as a dependency when defining a task like this:

task myTaskOnlyForDebugBuildType(dependsOn:assembleDebug) {
    //do smth
}

A proposed workaround from this answer would be this

task myTaskOnlyForDebugBuildType(dependsOn:"assembleDebug") {
    //do smth
}

or this

afterEvaluate {
    task myTaskOnlyForDebugBuildType(dependsOn:assembleDebug) {
        //do smth
    }
}

But both didn't work for me.

Answer 1

Here is a full example on how to do this inspired by this post: (android plugin v.0.9.2 and gradle 1.11 at the time of writing)

We are going to define a task that only runs when we build a "debugCustomBuildType"

android {
    ...
    buildTypes {
        debugCustomBuildType {
            //config
        }
   }
}

Define the task that should only be executed on a specific builtType/variant/flavor

task doSomethingOnWhenBuildDebugCustom {
    doLast {
       //task action
    }
}

Dynamically set the dependency when the tasks are added by gradle

tasks.whenTaskAdded { task ->
    if (task.name == 'generateDebugCustomBuildTypeBuildConfig') {
        task.dependsOn doSomethingOnWhenBuildDebugCustom 
    }
}

Here we use the "generateBuildConfig" task, but you can use any task that works for you (also see official docs)

• processManifest
• aidlCompile
• renderscriptCompile
• mergeResourcess.
• mergeAssets
• processResources
• generateBuildConfig
• javaCompile
• processJavaResources
• assemble

Don't forget to use the buildTypeSpecific task (generateBuildConfig vs. generateDebugCustomBuildTypeBuildConfig)

And that's it. It's a shame this workaround isn't well documented because for me this seems like one of the simplest requirements for a build script.

Answer 2

I achieved it like this:

android {
    ext.addDependency = {
        task, flavor, dependency ->
            def taskName = task.name.toLowerCase(Locale.US)
            if (taskName.indexOf(flavor.toLowerCase(Locale.US)) >= 0) {
                task.dependsOn dependency
            }
    }

    productFlavors {
        production {
        }
        other
    }

    task theProductionTask << {
        println('only in production')
    }

    tasks.withType(JavaCompile) {
        compileTask -> addDependency compileTask, "production", theProductionTask
    }
}

To be frank, I don't which locale is used to generate names for compile taks so toLowerCase(Locale.US) may be counterproductive.

Answer 3

This is the only solution that worked for me:

afterEvaluate {
    if (project.hasProperty("preReleaseBuild")){
        tasks.preReleaseBuild.dependsOn bundleJSRelease
    } else {
        tasks.preDebugBuild.dependsOn bundleJSDebug
    }
}

Answer 4

tasks.whenTaskAdded { task ->
    if (task.name.contains("assembleRelease")) {
        task.getDependsOn().add({
            // add your logic here
        })
    }
}