[TQC+ Android]公尺與英呎轉換_202

Android 2.1 API 7 版本原始題目載點：http://db.tt/hHVh21bO

僑光科技大學 蔡存孝老師 解說參考：http://rs2.ocu.edu.tw/~tsay/files/TQC202.pdf

GDD02.java - Activity主體
因為layout為線性排列所以擺放Button時，需要再選擇relation layout再擺放兩個Button

package COM.TQC.GDD02;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class GDD02 extends Activity implements OnClickListener{
    private TextView result;
    private EditText input_value;
    private Button submit01, submit02;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        result = (TextView) findViewById(R.id.result);
        input_value = (EditText) findViewById(R.id.input_value);
        submit01 = (Button) findViewById(R.id.submit01);
        submit02 = (Button) findViewById(R.id.submit02);
        
        submit01.setOnClickListener(this);
        submit02.setOnClickListener(this);
    }

    public void onClick(View v) {
        String r = input_value.getText().toString();
        
        if (v == submit01)
            r += ".0公尺 = " + String.format("%.2f", Double.parseDouble(r) * 3.28) + "英呎";
        else if (v == submit02)
            r += ".0英呎 = "+ String.format("%.2f", Double.parseDouble(r) * 0.3048) + "公尺";
        
        result.setText(r);
    }
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.menu, menu);
        return true;
    }

    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case R.id.menu_reset:
            resetValue();
            break;
        }
        return true;
    }

    private void resetValue() {
        result.setText("");
        input_value.setText("");
    }
}