about activities in android
<p>please give me the solution</p>

<pre><code>public class Calc extends Activity implements OnClickListener 
{
       private Button clr;            
       clr=(Button)findViewById(R.id.Button01);
}

public void onClick(View v)
{
   case R.id.Button01:       
       tv1.setText("REF");
       if( ref_flg==true)
       {
          final AlertDialog alertDialog = new AlertDialog.Builder(this).create();
          alertDialog.setTitle("Reset...");
          alertDialog.setMessage("REF was already entered");
          alertDialog.setButton2("OK", new DialogInterface.OnClickListener()
          {
              public void onClick(DialogInterface dialog, int which) {
                  // here you can add functions
                  dialog.dismiss();
              }
          });
          alertDialog.setIcon(R.drawable.icon);
          alertDialog.show();
       } 
}
</code></pre>

<p>so my question is that how i can write the code in case button01 in another activity and get the result from it.</p>
