Android 项目 日志

[xuxiaowei]

Android 项目 日志

源码

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FileLogger

package cn.com.xuxiaowei.utils

import android.content.Context
import android.util.Log
import java.io.File
import java.io.FileWriter
import java.io.IOException
import java.text.SimpleDateFormat
import java.util.Date
import java.util.Locale
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.SupervisorJob
import kotlinx.coroutines.launch

object FileLogger {
    private const val TAG = "FileLogger"

    // 使用 ThreadLocal 确保 SimpleDateFormat 的线程安全
    private val dateFormat =
        ThreadLocal.withInitial { SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS", Locale.getDefault()) }
    private val fileNameFormat =
        ThreadLocal.withInitial { SimpleDateFormat("yyyy-MM-dd", Locale.getDefault()) }

    // 使用专用的单线程调度器执行文件写入，以防止竞争条件，并避免阻塞主线程。
    private val logScope = CoroutineScope(Dispatchers.IO + SupervisorJob())

    fun log(context: Context, filename: String, tag: String, message: String) {
        // 立即输出到 Logcat
        Log.d(tag, message)

        // 异步写入到文件
        logScope.launch { writeLogToFile(context, filename, tag, message) }
    }

    private fun writeLogToFile(context: Context, filename: String, tag: String, message: String) {
        try {
            // 获取外部存储的私有目录：
            // /storage/emulated/0/Android/data/cn.com.xuxiaowei/files/logs/
            val logDir = context.getExternalFilesDir("logs")
            if (logDir != null) {
                if (!logDir.exists()) {
                    logDir.mkdirs()
                }

                val currentDate = Date()
                val dateStr = fileNameFormat.get()?.format(currentDate) ?: ""
                val fileName = "${filename}_log_$dateStr.txt"
                val logFile = File(logDir, fileName)

                val timestamp = dateFormat.get()?.format(currentDate) ?: ""
                val logEntry = "$timestamp $tag: $message\n"

                // 以追加方式写入文件
                FileWriter(logFile, true).use { writer -> writer.append(logEntry) }
            }
        } catch (e: IOException) {
            Log.e(TAG, "Error writing log to file", e)
        }
    }
}

App

package cn.com.xuxiaowei

import android.app.Application
import android.os.Build
import cn.com.xuxiaowei.utils.FileLogger

class App : Application() {
    override fun onCreate() {
        super.onCreate()

        val appVersion = try {
            val pm = packageManager
            val pi = pm.getPackageInfo(packageName, 0)
            val versionName = pi.versionName ?: "unknown"
            val versionCode = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
                pi.longVersionCode.toString()
            } else {
                @Suppress("DEPRECATION")
                pi.versionCode.toString()
            }
            "$versionName($versionCode)"
        } catch (e: Exception) {
            "unknown"
        }

        val deviceInfo = "model=${Build.MODEL}, brand=${Build.BRAND}, sdk=${Build.VERSION.SDK_INT}"
        FileLogger.log(this, "startup", "App", "App started version=$appVersion, $deviceInfo")
    }
}

MainActivity

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        FileLogger.log(this, "startup", "MainActivity", "onCreate")
        enableEdgeToEdge()
        setContent {
            XuxiaoweiTheme {
                XuxiaoweiApp()
            }
        }
    }
}

AndroidManifest.xml

    <application
        android:name=".App">
    </application>

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