Anko Commons – Logging

Contents

• Using AnkoLogger in your project
• Trait-like style
• Logger object style

Using AnkoLogger in your project

AnkoLogger is inside the anko-commons artifact. Add it as a dependency to your build.gradle:

dependencies {
    compile "org.jetbrains.anko:anko-commons:$anko_version"
}

Trait-like style

Android SDK provides android.util.Log class with some logging methods. Usage is pretty straightforward though the methods require you to pass a tag argument. You can eliminate this with using AnkoLogger trait-like interface:

class SomeActivity : Activity(), AnkoLogger {
    private fun someMethod() {
        info("London is the capital of Great Britain")
        debug(5) // .toString() method will be executed
        warn(null) // "null" will be printed
    }
}

android.util.Log	AnkoLogger
v()	verbose()
d()	debug()
i()	info()
w()	warn()
e()	error()
wtf()	wtf()

The default tag name is a class name (SomeActivity in this case) but you can easily change it by overriding the loggerTag property.

Each method has two versions: plain and lazy (inlined):

info("String " + "concatenation")
info { "String " + "concatenation" }

Lambda result will be calculated only if Log.isLoggable(tag, Log.INFO) is true.

Logger object style

You can also use AnkoLogger as a plain object.

class SomeActivity : Activity() {
    private val log = AnkoLogger(this.javaClass)
    private val logWithASpecificTag = AnkoLogger("my_tag")

    private fun someMethod() {
        log.warning("Big brother is watching you!")
    }
}