スピナー

ボタンをクリックすると、スピナーで選択した計算をする。

選択肢は、たし算、ひき算、かけ算の３つ。結果をエディットテキスト３に表示する。

********************　　MainActivity.java　　********************

package jp.lesson.studyandroid;

import android.os.Bundle;

import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.ArrayAdapter;

public class MainActivity extends Activity {

   
    private EditText edit1, edit2, edit3;
    private Button btn1;
    private Spinner spi01;

    @Override

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
       
        setSpinners();  /* spinner1 */

        edit1 = (EditText) findViewById(R.id.editText1);

        edit2 = (EditText) findViewById(R.id.editText2);
        edit3 = (EditText) findViewById(R.id.editText3);
        btn1 = (Button) findViewById(R.id.button1);

        btn1.setOnClickListener(new View.OnClickListener() {

           
            public void onClick(View v) {
                String s1 = edit1.getText().toString();
                String s2 = edit2.getText().toString();
                float f1 = Float.valueOf(s1);
                float f2 = Float.valueOf(s2);
                float f3;
               
                String item = (String)spi01.getSelectedItem();
                if(item.equals("たし算")){
                    f3 = f1 + f2;
                }
                else if(item.equals("ひき算")){
                    f3 = f1 - f2;
                }
                else {
                    f3 = f1 * f2;
                }
                edit3.setText(Float.toString(f3));
            }
        });
       
    }
   
    private void setSpinners(){
        String[] labels = getResources().getStringArray(R.array.spinner_label);
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, labels);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
       
        spi01 = (Spinner)findViewById(R.id.spinner1);
        spi01.setAdapter(adapter);
    }
}

********************　　activity_main.xml　　********************

    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="vertical" >

        <Spinner

            android:id="@+id/spinner1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:prompt="@string/spinnerprompt" />

        <EditText

            android:id="@+id/editText1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10"
            android:inputType="numberDecimal" >

            <requestFocus />

        </EditText>

        <EditText

            android:id="@+id/editText2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10"
            android:inputType="numberDecimal" />

        <Button

            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/btn" />

        <EditText

            android:id="@+id/editText3"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10"
            android:inputType="numberDecimal" />

    </LinearLayout>

********************　　strings.xml　　********************

<resources>

    <string name="app_name">StudyAndroid</string>

    <string name="menu_settings">Settings</string>
    <string name="title_activity_main">MainActivity</string>
    <string name="btn">ボタン</string>
    <string name="spinnerprompt">どの計算をする？</string>
    <string-array name="spinner_label">
        <item >たし算</item>
        <item >ひき算</item>
        <item >かけ算</item>
    </string-array>

</resources>