Android學習手冊-Spinner

Spinner 下拉式選單

1. 在strings.xml中建立字串陣列，再將此字串陣列設定給spinner元件成為選單

<resources>
    <string name="app_name">spinner</string>
    <string-array name="gender_list">
        <item>男生</item>
        <item>女生</item>
    </string-array>
</resources>

2. 在介面布局檔(activity_main.xml)中加入spinner元件，並設定好屬性

<Spinner
    android:id="@+id/spnGender"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginLeft="20dp"
    android:layout_marginTop="20dp"
    android:entries="@array/gender_list" />

3. MainActivity.java中取得spiinner元件，並設定處理程序

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    Spinner mspnGender = findViewById(R.id.spnGender);
    mspnGender.setOnItemSelectedListener(new Spinner.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            //選擇選項要做的事
            switch (position){
                case 0:
                    mGender = "男生";
                    break;
                case 1:
                    mGender = "";
                    break;
            }
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {
            //沒有選擇選項要做的事
        }
    });