Kotlin] 내부저장소 저장 & 가져오기

https://www.javatpoint.com/kotlin-android-read-and-write-internal-storage

Kotlin Android Read and Write Internal Storage - javatpoint

//저장버튼 누르면
 saveButton.setOnClickListener {
            val text = textField.text.toString()
            when{
                TextUtils.isEmpty(text) -> Toast.makeText(applicationContext, "텍스트 볏다", Toast.LENGTH_LONG).show()

                else -> {
                    saveToInnerStorage(text, filename)
                    Toast.makeText(applicationContext,"${text}가 저장되엇읍니다",Toast.LENGTH_LONG).show()
                    textField.setText("초기화요")
                }
            }
}

//불러오기 버튼
loadButton.setOnClickListener {
      try {
           textField.setText(loadFromInnerStorage(filename))
       }catch (e : FileNotFoundException){
            Toast.makeText(applicationContext, "저장된 텍스트 업승ㅁ", Toast.LENGTH_LONG).show()
       }
}


// 내부 저장소에 저장 
fun saveToInnerStorage(text: String, filename: String ){
        // 다른 앱에서는 접근불가
        val fileOutputStream = openFileOutput(filename, Context.MODE_PRIVATE)

        fileOutputStream.write(text.toByteArray())
        fileOutputStream.close()
}

// 저장된거 가져오기 
fun loadFromInnerStorage(filename: String) :String{
    val fileInputStream = openFileInput(filename)

    return fileInputStream.reader().readText()
}