Eclipse - Workspace in use or cannot be created chose a different one

import android.content.Context;
import android.media.AudioManager;
import android.media.SoundPool;

public class SoundManager
{
  private SoundPool soundPool;
  private int[] sm;
  Context context;

  public SoundManager(Context context) {
    this.context = context;
    soundPool = new SoundPool(4, AudioManager.STREAM_MUSIC, 0);
    sm = new int[2];
    // fill your sounds
    sm[0] = soundPool.load(context, R.raw.my_sound1, 1);
    sm[1] = soundPool.load(context, R.raw.my_sound2, 1);
  }

  public final void playSound(int sound) {
      AudioManager mgr = (AudioManager)context.getSystemService(
          Context.AUDIO_SERVICE);  
      float streamVolumeCurrent =
          mgr.getStreamVolume(AudioManager.STREAM_MUSIC);
      float streamVolumeMax = mgr.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
      float volume = streamVolumeCurrent / streamVolumeMax;
      soundPool.play(sm[sound], volume, volume, 1, 0, 1f);
  }

  public final void cleanUpIfEnd() {
    sm = null;
    context = null;
    soundPool.release();
    soundPool = null;
  }
}

public class MainActivity extends Activity {
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {

		// CONSTRUCTOR
		public SampleView(Context context) {
			super(context);
			setFocusable(true);

		}

		@Override
		protected void onDraw(Canvas canvas) {

			canvas.drawColor(Color.CYAN);
			Paint p = new Paint();
			// smooths
			p.setAntiAlias(true);
			p.setColor(Color.RED);
			p.setStyle(Paint.Style.STROKE); 
			p.setStrokeWidth(4.5f);
			// opacity
			//p.setAlpha(0x80); //
 
			canvas.drawOval(new RectF(50, 50, 20, 40), p);;
		}

	}
}

 <TextView
        android:id="@+id/first_element_id"
        .........
 />
    <TextView
        android:id="@+id/second_element_id"
        android:layout_below="@id/first_element_id"
        ..........
 />

public class Main extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        try {
        setContentView(R.layout.main);
        
			ListView mlistView = (ListView) findViewById(R.id.idListView);
			mlistView.setAdapter(new ArrayAdapter<String>(this,
			        android.R.layout.simple_list_item_1, 
			        new String[] {"Game", "Help", "Home site"}));
    
        mlistView.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {
              // When clicked, show a toast with the TextView text Game, Help, Home
              Toast.makeText(getApplicationContext(), ((TextView) view).getText(),
                  Toast.LENGTH_SHORT).show();
              String sText = ((TextView) view).getText().toString();
              Intent intent = null;
              if(sText.equals("Game"))
              intent = new Intent(getBaseContext(),
						Game.class);
              //else if(sText.equals("Help")) ..........

              if(intent != null)
				startActivity(intent);              
            }
          });
        } catch (Exception e) {
        	// TODO Auto-generated catch block
        	e.printStackTrace();
        }
    
    }
}

        <activity android:name=".Game" android:label="GameLabel">
        </activity>

package cz.okhelp.listview;

import android.app.Activity;
import android.os.Bundle;

public class Game extends Activity{
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        // you have to create game.xml 
        setContentView(R.layout.game);
    }
}

public class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        LinearLayout layout = (LinearLayout) findViewById(R.id.layout);
            TextView textView = new TextView(this);
            textView.setText("Text View ");
            LinearLayout.LayoutParams p = new LinearLayout.LayoutParams(
                    LinearLayout.LayoutParams.FILL_PARENT,
                    LinearLayout.LayoutParams.WRAP_CONTENT
            );
            layout.addView(textView, p);

            Button buttonView = new Button(this);
            buttonView.setText("Button");
            buttonView.setOnClickListener(mThisButtonListener);
            layout.addView(buttonView, p);
        
    }
    private OnClickListener mThisButtonListener = new OnClickListener() {
        public void onClick(View v) {
            Toast.makeText(MainActivity.this, "Hello !",
                    Toast.LENGTH_LONG).show();
        }
    };
}