# Android Studio下拉式選單

###### tags: `Android Studio`
---

<string-array name="gender_list">
    <item>男</item>
    <item>女</item>
</string-array>

新增一個下拉選單按鈕
ID 設為 spinnerGender



package com.example.marriagesuggestion;
//系統檔案
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;

//引入程式內容，這裡寫的是元件名稱
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Spinner;

//主程式開始囉~
public class MainActivity extends AppCompatActivity {
    //先設定等一下要使用的變數，這裡我們設定為私密的元件變數
    private EditText mEditGender, mEdtAge;
    private TextView mTextResult;
    private Button mBtnDo;
    private String msGender;

    //下面是系統預設的內容，先不去動他
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //把在activity_main設定好的按鈕、輸入框的ID提取到這裡
//        mEditGender = findViewById(R.id.editGender);
        mEdtAge = findViewById(R.id.editAge);
        mTextResult = findViewById(R.id.txtResult);
        mBtnDo = findViewById(R.id.btnDo);

        //監聽按鈕，使用btnDoOnclick這個物件方法
        mBtnDo.setOnClickListener(btnDoOnclick);

        Spinner spinnerGender = findViewById(R.id.spinnerGender);
        spinnerGender.setOnItemSelectedListener(spinnerGenderOnItemSelected);
    }

    private View.OnClickListener btnDoOnclick = new View.OnClickListener(){
        @Override
        //取得使用者出入的性別和年齡
        public void onClick(View v){
            //取得使用者輸入的值
//            String strSex = mEditGender.getText().toString();
            int iAge = Integer.parseInt(mEdtAge.getText().toString());

            //從按鈕取得使用者出入的字串
            String strSug = getString(R.string.suggestion);

            //判斷內容
            if(msGender.equals(getString(R.string.male))){
                if(iAge < 28){
                    strSug += getString(R.string.not_hurry);
                }else if(iAge > 33){
                    strSug += getString(R.string.get_married);
                }else{
                    strSug += getString(R.string.find_couple);
                }
            }else{
                if(iAge < 25){
                    strSug += getString(R.string.not_hurry);
                }else if(iAge > 30){
                    strSug += getString(R.string.get_married);
                }else{
                    strSug += getString(R.string.find_couple);
                }
            };
            //顯示在指定的位置
            mTextResult.setText(strSug);
        }
    };
    private AdapterView.OnItemSelectedListener spinnerGenderOnItemSelected = new AdapterView.OnItemSelectedListener(){
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l){
            switch (i){
                case 0:
                    msGender = "male";
                    break;
                case 1:
                    msGender = "";
                    break;
            }
        }

        @Override
        public void onNothingSelected(AdapterView<?> adapterView){

        }
    };

}

---
<span class="code1"></span>
<style>
h2 {
color: #2383B8;
}
h3 {
color: #1AA340;
}
h4 {
color: white;
background-color: #2383B8;
padding:8px;
}

.code1 {
padding: 2px 4px;
font-size: 90%;
color: #c7254e;
background-color: #f9f2f4;
border-radius: 4px;
font-family:'Fira Code';
}
.code {
padding: 2px 4px;
font-size: 90%;
font-family:'Fira Code';
}
</style>