title: How to detect the Top of page in webView?
body: <p>I have a <code>WebView</code> . I want to detect when i am on the top of the page whenever i scroll my page all the way up. How do i do that?</p>
  
  <p>I have extended </p>
  
  <pre><code>implements OnScrollListener
  </code></pre>
  
  <p>and it added these two automatically </p>
  
  <pre><code>@Override
  public void onScroll(AbsListView arg0, int arg1, int arg2, int arg3) {
      // TODO Auto-generated method stub
  
  }
  
  @Override
  public void onScrollStateChanged(AbsListView arg0, int arg1) {
      // TODO Auto-generated method stub
  
  }
  </code></pre>
  
  <p>however, i cannot add </p>
  
  <pre><code>@Override
  protected void onScrollChanged(int l, int t, int oldl, int oldt) { 
  
       if(view.getTop()==t){
          // reaches the top end
          }
  
      View view = (View) getChildAt(getChildCount()-1); 
      int diff = (view.getBottom()-(getHeight()+getScrollY()+view.getTop()));// Calculate the scrolldiff 
       if( diff &lt;= 0 ){ 
          // if diff is zero, then the bottom has been reached
           Log.d(ScrollTest.LOG_TAG, "MyScrollView: Bottom has been reached" );
               }
      super.onScrollChanged(l, t, oldl, oldt); 
  }
  </code></pre>
  
  <p>the error it gives me is <strong>"The method onScrollChanged(int, int, int, int) of type MainActivity must override or implement a supertype method"</strong></p>