Spinner

 

spinner에 항목을 선택하면 텍스트 뷰에 보여주도록 하자

 

1. activity_main

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".MainActivity">

    <Spinner
            android:id="@+id/spinner"
            android:layout_centerHorizontal="true"
            android:layout_width="390dp"
            android:layout_height="67dp"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintBottom_toTopOf="@+id/textView"
            app:layout_constraintVertical_bias="0.931"/>

    <TextView
            android:id="@+id/textView"
            android:layout_width="269dp"
            android:layout_height="64dp"
            android:text="Hello World!"
            android:gravity="center"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintHorizontal_bias="0.501"
            app:layout_constraintVertical_bias="0.604"/>
</androidx.constraintlayout.widget.ConstraintLayout>

 

2. app - main - java폴더 내 메인 패키지 폴더 우클릭 - 새로만들기 - XML - Layout XML File - item_spinner로 생성

item_spinner.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/tvItemSpinner"
        android:layout_width="match_parent"
        android:layout_height="45dp"
        android:paddingTop="10dp"
        android:paddingStart="30dp"
        android:textColor="@android:color/black"
        android:textSize="15sp"
        android:paddingLeft="30dp"/>

 

3. app - src - main - res - values 우클릭 후 새로만들기 - XML - Values XML File - array이름으로 xml파일 생성

array.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string-array name="fruit">
        <item>과일선택</item>
        <item>귤</item>
        <item>파인애플</item>
        <item>자몽</item>
        <item>망고</item>
    </string-array>
</resources>

 

4. MainActivity.kt

class MainActivity : AppCompatActivity() {

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

        setupSpinnerFruit()
        setupSpinnerHandler()
    }

    // spinner에 값을 설정하는 함수
    fun setupSpinnerFruit(){
        //val fruit = arrayOf("과일 선택", "사과", "배", "바나나", "포도")
        val fruit = resources.getStringArray(R.array.fruit)
        // 어댑터에 배열과 xml을 적용한다
        val adapter = ArrayAdapter(this, R.layout.item_spinner, fruit)

        // spinner에 적용
        val spinner = findViewById<Spinner>(R.id.spinner)
        spinner.adapter = adapter
    }

    // 선택시 결과를 출력해주는 함수
    fun setupSpinnerHandler(){
        val spinner = findViewById<Spinner>(R.id.spinner)
        val textView = findViewById<TextView>(R.id.textView)

        spinner.onItemSelectedListener = object :AdapterView.OnItemSelectedListener{
            override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
                textView.text = "선택됨: $position ${spinner.getItemAtPosition(position)}"
            }
            override fun onNothingSelected(p0: AdapterView<*>?) {
            }
        }
    }
}

 

 

결과물