Documentation

1. Installation

Add the SLF4J API and logback-android to your module's build.gradle:

dependencies {
  implementation 'org.slf4j:slf4j-api:2.0.7'
  implementation 'com.github.tony19:logback-android:3.0.0'
}

logback-android is published as JDK-specific artifacts — pick the one that matches your minimum SDK:

2. Configuration

On startup, logback-android looks for logback.xml in your app's assets directory (app/src/main/assets/logback.xml). If no configuration is found, logging is silently disabled — so this file is not optional. A minimal config that logs to logcat:

<configuration
  xmlns="https://tony19.github.io/logback-android/xml"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="https://tony19.github.io/logback-android/xml https://cdn.jsdelivr.net/gh/tony19/logback-android/logback.xsd"
>
  <appender name="logcat" class="ch.qos.logback.classic.android.LogcatAppender">
    <tagEncoder>
      <pattern>%logger{12}</pattern>
    </tagEncoder>
    <encoder>
      <pattern>[%-20thread] %msg</pattern>
    </encoder>
  </appender>

  <root level="DEBUG">
    <appender-ref ref="logcat" />
  </root>
</configuration>

Prefer not to write XML by hand? The Config Editor builds this file for you interactively. Programmatic (in-code) configuration is also supported.

Appender reference

Special properties

These variables are resolved at runtime and can be used anywhere in your config:

Providing the Android context

Resolving the special properties requires an Android Context. By default the framework uses a reflection-based workaround, but Google's restrictions on non-SDK interfaces may break it in the future. The recommended approach is to provide the context explicitly, before any logging occurs:

public class MyApplication extends Application {
  @Override
  public void onCreate() {
    super.onCreate();
    // Assuming no logging occurs before this
    AndroidContextUtil.setApplicationContext(this);
  }
}

3. Reference material