LifeCycleObserveableLogger

LifeCycleObserveableLogger.kt

import android.util.Log
import androidx.lifecycle.Lifecycle
import androidx.lifecycle.LifecycleObserver
import androidx.lifecycle.OnLifecycleEvent

object IndentProvider {
    private var depth = 0
    private const val SPACE = "  "

    fun getAndIncrement(): String {
        require(depth >= 0)
        val indentSpace = (0 until depth).joinToString(separator = "") { SPACE }
        depth++
        return indentSpace
    }

    fun incrementAndGet(): String {
        require(depth >= 0)
        depth++
        return (0 until depth).joinToString(separator = "") { SPACE }
    }

    fun getAndDecrement(): String {
        require(depth >= 0)
        val indentSpace = (0 until depth).joinToString(separator = "") { SPACE }
        depth--
        check(depth >= 0)
        return indentSpace
    }

    fun decrementAndGet(): String {
        require(depth >= 0)
        depth--
        check(depth >= 0)
        return (0 until depth).joinToString(separator = "") { SPACE }
    }

    fun current(): String {
        require(depth >= 0)
        return (0 until depth).joinToString(separator = "") { SPACE }
    }
}

class IndentLogger(tag: String) {
    private val prefix: String = run {
        val tagSize = tag.length
        (0 until 13).map { if (it < tagSize) tag[it] else " " }.joinToString(separator = "")
    }
    fun logAndIncrement(tag: String, msg: String) {
        Log.d(tag, "${IndentProvider.getAndIncrement()}[$prefix]-$msg")
    }

    fun decrementAndLog(tag: String, msg: String) {
        Log.d(tag, "${IndentProvider.decrementAndGet()}[$prefix]-$msg")
    }

    fun log(tag: String, msg: String) {
        Log.d(tag, "${IndentProvider.current()}[$prefix]-$msg")
    }
}

class LifeCycleObservableLogger(val logger: IndentLogger) : LifecycleObserver {
    companion object {
        const val TAG = "LifeCycleLog"
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_CREATE)
    fun onCreated() = logger.logAndIncrement(TAG, "ON_CREATE")

    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    fun onStarted() = logger.logAndIncrement(TAG, "ON_START")

    @OnLifecycleEvent(Lifecycle.Event.ON_RESUME)
    fun onResumed() = logger.logAndIncrement(TAG, "ON_RESUME")

    @OnLifecycleEvent(Lifecycle.Event.ON_PAUSE)
    fun onPaused() = logger.decrementAndLog(TAG, "ON_PAUSE")

    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    fun onStopped() = logger.decrementAndLog(TAG, "ON_STOP")

    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    fun onDestroyed() = logger.decrementAndLog(TAG, "ON_DESTROY")

    fun onSaveInstanceState() = logger.log(TAG, "ON_SAVE_INSTANCE_STATE")
    fun onRestoreSavedInstanceState() = logger.log(TAG, "ON_RESTORE_SAVED_INSTANCE_STATE")
    fun onConfigurationChanged() = logger.log(TAG, "ON_CONFIGURATION_CHANGED")
    fun onCreateView() = logger.log(TAG, "ON_CREATE_VIEW")
    fun onViewCreated() = logger.log(TAG, "ON_VIEW_CREATED")
    fun onDestroyView() = logger.log(TAG, "ON_DESTROY_VIEW")
    fun onViewStateRestored() = logger.log(TAG, "ON_VIEW_STATE_RESTORED")
}

• No configChanges options.

launch

D/LifeCycleLog: [FirstFragment]-ON_CREATE
D/LifeCycleLog:   [MainActivity ]-ON_CREATE
D/LifeCycleLog:     [FirstFragment]-ON_CREATE_VIEW
D/LifeCycleLog:     [FirstFragment]-ON_VIEW_CREATED
D/LifeCycleLog:     [FirstFragment]-ON_VIEW_STATE_RESTORED
D/LifeCycleLog:     [FirstFragment]-ON_START
D/LifeCycleLog:       [MainActivity ]-ON_START
D/LifeCycleLog:         [FirstFragment]-ON_RESUME
D/LifeCycleLog:           [MainActivity ]-ON_RESUME

launch other app and back.

 D/LifeCycleLog:           [MainActivity ]-ON_PAUSE
 D/LifeCycleLog:         [FirstFragment]-ON_PAUSE
 D/LifeCycleLog:       [MainActivity ]-ON_STOP
 D/LifeCycleLog:     [FirstFragment]-ON_STOP
 D/LifeCycleLog:     [FirstFragment]-ON_SAVE_INSTANCE_STATE
 D/LifeCycleLog:     [MainActivity ]-ON_SAVE_INSTANCE_STATE
 D/LifeCycleLog:     [FirstFragment]-ON_START
 D/LifeCycleLog:       [MainActivity ]-ON_START
 D/LifeCycleLog:         [FirstFragment]-ON_RESUME
 D/LifeCycleLog:           [MainActivity ]-ON_RESUME

launch other app and back. (don't keep activity)

D/LifeCycleLog:           [MainActivity ]-ON_PAUSE
D/LifeCycleLog:         [FirstFragment]-ON_PAUSE
D/LifeCycleLog:       [MainActivity ]-ON_STOP
D/LifeCycleLog:     [FirstFragment]-ON_STOP
D/LifeCycleLog:     [FirstFragment]-ON_SAVE_INSTANCE_STATE
D/LifeCycleLog:     [MainActivity ]-ON_SAVE_INSTANCE_STATE
D/LifeCycleLog:   [MainActivity ]-ON_DESTROY
D/LifeCycleLog:   [FirstFragment]-ON_DESTROY_VIEW
D/LifeCycleLog: [FirstFragment]-ON_DESTROY
D/LifeCycleLog: [FirstFragment]-ON_CREATE
D/LifeCycleLog:   [MainActivity ]-ON_CREATE
D/LifeCycleLog:     [FirstFragment]-ON_CREATE_VIEW
D/LifeCycleLog:     [FirstFragment]-ON_VIEW_CREATED
D/LifeCycleLog:     [FirstFragment]-ON_VIEW_STATE_RESTORED
D/LifeCycleLog:     [FirstFragment]-ON_START
D/LifeCycleLog:       [MainActivity ]-ON_START
D/LifeCycleLog:         [MainActivity ]-ON_RESTORE_SAVED_INSTANCE_STATE
D/LifeCycleLog:         [FirstFragment]-ON_RESUME
D/LifeCycleLog:           [MainActivity ]-ON_RESUME

rotate

same recreation log with don't keep activity.

D/LifeCycleLog:           [MainActivity ]-ON_PAUSE
D/LifeCycleLog:         [FirstFragment]-ON_PAUSE
D/LifeCycleLog:       [MainActivity ]-ON_STOP
D/LifeCycleLog:     [FirstFragment]-ON_STOP
D/LifeCycleLog:     [FirstFragment]-ON_SAVE_INSTANCE_STATE
D/LifeCycleLog:     [MainActivity ]-ON_SAVE_INSTANCE_STATE
D/LifeCycleLog:   [MainActivity ]-ON_DESTROY
D/LifeCycleLog:   [FirstFragment]-ON_DESTROY_VIEW
D/LifeCycleLog: [FirstFragment]-ON_DESTROY
D/LifeCycleLog: [FirstFragment]-ON_CREATE
D/LifeCycleLog:   [MainActivity ]-ON_CREATE
D/LifeCycleLog:     [FirstFragment]-ON_CREATE_VIEW
D/LifeCycleLog:     [FirstFragment]-ON_VIEW_CREATED
D/LifeCycleLog:     [FirstFragment]-ON_VIEW_STATE_RESTORED
D/LifeCycleLog:     [FirstFragment]-ON_START
D/LifeCycleLog:       [MainActivity ]-ON_START
D/LifeCycleLog:         [MainActivity ]-ON_RESTORE_SAVED_INSTANCE_STATE
D/LifeCycleLog:         [FirstFragment]-ON_RESUME
D/LifeCycleLog:           [MainActivity ]-ON_RESUME