Logging

FlixelLogger is the framework's structured logging system. You write to it through the static helpers on Flixel, and it delivers each entry to both the console and (optionally) a rolling log file. The debugger's Log window listens to it in real time.

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Writing log messages

Java

// Three severity levels, each with an optional tag.
Flixel.info("Spawner", "Spawned enemy at (100, 200)");
Flixel.warn("Physics", "Velocity clamped: " + obj.getVelocityX());
Flixel.error("SaveSystem", "Failed to write save file", exception);

Kotlin

// Three severity levels, each with an optional tag.
Flixel.info("Spawner", "Spawned enemy at (100, 200)")
Flixel.warn("Physics", "Velocity clamped: ${obj.velocityX}")
Flixel.error("SaveSystem", "Failed to write save file", exception)

The tag is free-form text. Use it as a module or subsystem identifier so you can filter messages in the Log window (or grep in a log file) when debugging a specific system.

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Enabling file logging

Java

// In your game's constructor or create():
Flixel.log.startFileLogging();

Kotlin

// In your game's constructor or create():
Flixel.log.startFileLogging()

Log file location

Context	Default location
Running from IDE	<project root>/logs/
Running from a JAR	logs/ next to the JAR
Custom	Set via Flixel.log.setLogsFolder("path/to/logs")

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Custom log listeners

Attach a listener to receive every log entry as a FlixelLogEntry (a record exposing level(), tag(), and message()):

Java

Flixel.log.addLogListener(entry -> {
  if (entry.level() == FlixelLogLevel.ERROR) {
    crashReporter.submit(entry.tag(), entry.message());
  }
});

Kotlin

Flixel.log.addLogListener { entry ->
  if (entry.level() == FlixelLogLevel.ERROR) {
    crashReporter.submit(entry.tag(), entry.message())
  }
}

Listeners receive entries even in RELEASE builds where the debug overlay is absent. This makes them the right hook for crash reporting, telemetry, or an in-game developer console of your own design.

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Log modes

Mode	What it prints
SIMPLE	File location + line + message only.
DETAILED	Level + timestamp + tag + message. Always used for file output.

Java

Flixel.log.setLogMode(FlixelLogMode.DETAILED);

Kotlin

Flixel.log.logMode = FlixelLogMode.DETAILED