title: show/hide an listView on a buttonClick
body: <pre><code>final ImageView patientAllergyImage = (ImageView) findViewById(R.id.image);
  patientAllergyImage.setOnClickListener(new OnClickListener() {
  
      @Override
      public void onClick(View v) {
          // TODO Auto-generated method stub
          patientAllergyImage.setImageDrawable(getResources().
                  getDrawable(R.drawable.nav_down_green));
          List.setVisibility(View.GONE);
      }
  });
  </code></pre>
  
  <p>I am making my List to Hide, but how do i show it when i click on the same button. I am not able to keep a boolean to check whether its clicked or not as it saying... <code>The final local variable clicked cannot be assigned, since it is defined in an enclosing type</code> neither an <code>non</code> <code>final</code> variable</p>