ciao a tutti.
come inizio di programmazione per Android, ho cercato degli esempi di codice in rete
ma come sfortuna vuole qualche cosa non va..

Eclipse mi ritorna un errore sulla classe R in quanto con riconosce array.
La classe R da quello che ho capito si autogenera quindi non posso neppure applicare le soluzioni proposte da Eclipse (Create field Array in type R)

ArrayAdapter seleziona_operazione_array = ArrayAdapter.createFromResource(this, R.array.operazione_select,

avate dei consigli?

Codice java
codice:
package calcolatrice.it;

import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

public class Calcolatrice extends Activity {
	Spinner Spinner1;
	Button Button1;
	Object itemSelected;
	EditText Text1, Text2;
	TextView Label1;
	String StringText1, StringText2;
	int RisultatoInt1, RisultatoInt2, RisultatoInt;
	Toast toast;

	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		Label1 = (TextView) findViewById(R.id.textView4);

		Spinner1 = (Spinner) findViewById(R.id.spinner1);
	
	ArrayAdapter seleziona_operazione_array = ArrayAdapter
				.createFromResource(this, R.array.operazione_select,
						android.R.layout.simple_spinner_item);
		seleziona_operazione_array
				.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
		Spinner1.setAdapter(seleziona_operazione_array);
		Spinner1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
			public void onItemSelected(AdapterView<?> parent, View arg1,
					int pos, long arg3) {
				Spinner1.getSelectedItemPosition();
			}

			public void onNothingSelected(AdapterView<?> arg0) {
			}
		});

		Text1 = (EditText) findViewById(R.id.editText1);
		Text2 = (EditText) findViewById(R.id.editText2);

		Button1 = (Button) findViewById(R.id.button1);
		Button1.setOnClickListener(new OnClickListener() {

			public void onClick(View arg0) {
				try {
					StringText1 = Text1.getText().toString();
					StringText2 = Text2.getText().toString();
					RisultatoInt1 = 0;
					RisultatoInt2 = 0;
					RisultatoInt = 0;
					int n = Spinner1.getSelectedItemPosition();

					if (n == 0) {
						int RisultatoInt1 = Integer.parseInt(StringText1);
						int RisultatoInt2 = Integer.parseInt(StringText2);
						int RisultatoInt = RisultatoInt1 + RisultatoInt2;
						Label1.setText("Risultato:  "
								+ Integer.toString(RisultatoInt));
					} else if (n == 1) {
						int RisultatoInt1 = Integer.parseInt(StringText1);
						int RisultatoInt2 = Integer.parseInt(StringText2);
						int RisultatoInt = RisultatoInt1 - RisultatoInt2;
						Label1.setText("Risultato:  "
								+ Integer.toString(RisultatoInt));
					} else if (n == 2) {
						int RisultatoInt1 = Integer.parseInt(StringText1);
						int RisultatoInt2 = Integer.parseInt(StringText2);
						int RisultatoInt = RisultatoInt1 * RisultatoInt2;
						Label1.setText("Risultato:  "
								+ Integer.toString(RisultatoInt));
					} else if (n == 3) {
						int RisultatoInt1 = Integer.parseInt(StringText1);
						int RisultatoInt2 = Integer.parseInt(StringText2);
						int RisultatoInt = RisultatoInt1 / RisultatoInt2;
						Label1.setText("Risultato:  "
								+ Integer.toString(RisultatoInt));
					}

				} catch (Exception e) {
					Toast.makeText(null, "Errore:" + e, Toast.LENGTH_LONG);
					toast.show();
				}

			}

		});

	}

};
layout main.xls

codice:
<?xml version="1.0" encoding="utf-8"?>
<AnalogClock android:id="@+id/AnalogClock1" android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    xmlns:android="http://schemas.android.com/apk/res/android">

    <TableLayout
        android:id="@+id/tableLayout1"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:editable="false"
            android:text="@string/ins_num"
            android:textColor="#009933" >
        </TextView>
    </TableLayout>

    <TableRow
        android:id="@+id/tableRow1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <EditText
            android:id="@+id/editText1"
            android:layout_width="match_parent"
            android:layout_height="40dp"
            android:numeric="integer"
            android:text="@string/ins_num" android:inputType="number">
        </EditText>
    </TableRow>

    <TableRow
        android:id="@+id/tableRow2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:id="@+id/textView2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Inserisci un&apos;altro numero:"
            android:textColor="#009933" >
        </TextView>
    </TableRow>

    <TableRow
        android:id="@+id/tableRow3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <EditText
            android:id="@+id/editText2"
            android:layout_width="match_parent"
            android:layout_height="40dp"
           android:inputType="textCapWords"
            android:numeric=""
         >
        </EditText>
    </TableRow>

    <TableRow
        android:id="@+id/tableRow4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </TableRow>

    <TextView
        android:id="@+id/textView3"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:text="@string/ins_num"
        android:textColor="#009933" >
    </TextView>

    <TableRow
        android:id="@+id/tableRow5"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <Spinner
            android:id="@+id/spinner1"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" >
        </Spinner>
    </TableRow>

    <TableRow
        android:id="@+id/tableRow6"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <Button
            android:id="@+id/button1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/ins_num"
            android:textColor="#ff3300" >
        </Button>
    </TableRow>

    <TextView
        android:id="@+id/textView4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/ins_num"
        android:textColor="#009933"
        android:textSize="20dp" >
    </TextView>

</AnalogClock>