title: How do I instantiate a class in android which is also an activity?
body: <p>In android, how can I create a <code>constructor</code> for a <code>class</code> which is also an <code>Activity</code>?</p>
  
  <p>My problem is, <p>I want to have two activity classes (estimateFare and Mapping) which both send data to a an activity class (<code>CalculateFare</code>). Mapping takes the data from real time network info, whereas estimateFare takes data from user input. I want <code>CalculateFare</code> to be able to use the data from either class to perform the calculation, although I have run into trouble with the <code>onCreate</code> method and the constructor for <code>CalculateFare</code>. When the class is called during runtime of the application I get the following message in the <code>LogCat</code>;</p>
  
  <pre><code>Unable to instantiate activity ComponentInfo. 
  </code></pre>
  
  <p>A snippet from CalculateFare is as follows;</p>
  
  <pre><code>    public class CalculateFare extends Activity {
          TextView t;
          static long length;
          static int dist;
          static int mMonth;
          static int mDay;
          public static double fare;
          double rate1 = 0, rate2a, rate2b, rate3, rate4a, rate4b;
          int remDist = 0;
          double remLength;
          private static int TTS_DATA_CHECK = 1;
          private TextToSpeech tts = null;
          private boolean ttsIsInit = false;
  
  
  
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.fare);
  
  }
  
  public CalculateFare(long length, int dist, int mMonth, int mDay)
  {
  }
  
  public static void setLength(long l)
  {
      length = l;
  }
  
  public static void setDist(int d)
  {
      dist = d;
  }
  
  public static void setDate(int m, int d)
  {
      mMonth = m;
      mDay = d;
  }
  
  public void calc()
  {
  </code></pre>
  
  <p>Any Advice much appreciated</p>