Kotlin function to make list from directory files

CreateListFileFromDirectory.kt

   fun listFilesInDirectory(directoryPath: String): List<File> {
        val directory = File(directoryPath)
        return directory.listFiles()?.toList() ?: emptyList()
    }
    
    //--- Implement Read text from file 
       fun readTextFromFile(filePath: String): String? {
        val file = File(filePath)
        if (!file.exists() || !file.isFile) {
            return null
        }
        val stringBuilder = StringBuilder()
        BufferedReader(FileReader(file)).use { reader ->
            var line = reader.readLine()
            while (line != null) {
                stringBuilder.append(line+ "\n")
                line = reader.readLine()
            }
        }
        return stringBuilder.toString()
    }
    
    
   // use this as 
    var filepath:String = intent.getStringExtra("filepath")!!
        var  content = readTextFromFile(filepath)