[안드로이드] EditText Box : 메시지 박스 Byte 표시 및 제한

위에 그림은 SMS 화면의 일부입니다.

SMS 와 비슷하게 메시지 박스를 만들고 Byte 표시 및 제한을 해보려고 합니다.

1. EditText Box : 메시지 박스

border_black_1dp.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
    <item >
        <shape android:shape="rectangle" >
            <stroke
                android:width="1dp"
                android:color="#000000" />
        </shape>
    </item>
</layer-list>

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:layout_margin="20dp">

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="250dp"
        android:orientation="vertical">

        <EditText
            android:id="@+id/etMessage"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:background="@drawable/border_black_1dp"
            android:gravity="start"
            android:hint="메시지를 입력해주세요."
            android:padding="10dp" />

        <TextView
            android:id="@+id/tvByte"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom"
            android:layout_marginEnd="5dp"
            android:gravity="end" />
    </FrameLayout>
</LinearLayout>

2. Byte 표시 및 제한

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val etText = findViewById<TextView>(R.id.etMessage)
        val tvByte = findViewById<TextView>(R.id.tvByte)

        etText.addTextChangedListener(object : TextWatcher {
            override fun beforeTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {

            }

            override fun onTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {
                val bytes: ByteArray?
                try {
                    // byte 표시 갱신 처리
                    bytes = charSequence.toString().toByteArray(charset("KSC5601"))
                    val strCount = bytes.size
                    tvByte.text = "$strCount / 80 Byte"
                } catch (ex: UnsupportedEncodingException) {
                    ex.printStackTrace()
                }
            }

            override fun afterTextChanged(editable: Editable) {
                val str = editable.toString()
                try {
                    // byte 제한을 넘었을 때 삭제 처리
                    val strBytes = str.toByteArray(charset("KSC5601"))
                    if (strBytes.size > 80) {
                        editable.delete(editable.length - 2, editable.length - 1)
                    }
                } catch (ex: Exception) {
                    ex.printStackTrace()
                }
            }
        })
    }
}

3. 결과

[참고자료]

https://hanyeop.tistory.com/64