title: translate a UIImageView down
body: <p>I am coding an iOS game and I am trying to move down an instance of a Tile (Tile being a subclass of UIImageView.) </p>
  
  <p>Precisely, what I want is having my instance of Tile moving from point A(x,y) to point B(x,y+70) in 0.20s.</p>
  
  <p>I already read that post, that describes a similar problem: <a href="https://stackoverflow.com/questions/13333361/change-position-of-the-uiimageview?rq=1">change position of the UIImageView</a></p>
  
  <p>I used the recommended code and adapted it to my case. So here is the code of the method I use: </p>
  
  <pre class="lang-cs prettyprint-override"><code>- (void) moveTileDown {
      [UIView animateWithDuration:0.20
                            delay:1.0
                          options: UIViewAnimationOptionCurveEaseIn
                       animations:^{
                           self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y + 70, self.frame.size.width, self.frame.size.height);
                       }
                       completion:^(BOOL finished){
                           NSLog(@"Done!");
                       }];
  }
  </code></pre>
  
  <p>But now, here is my problem. Instead of going from A(x,y) to B(x,y+70), when the method is called, my tile Jumps to C(x,y-70) and comes back to A in 0.20s.</p>
  
  <p>In order to give more info, the moveTileDown method is called from a for loop that takes place in another controller </p>
  
  <pre><code>        for (int i=0; i &lt;firstTileRow; i++){
              [[[_lines objectAtIndex:i] objectAtIndex:firstTileColumn] moveTileDown];
              [[[_lines objectAtIndex:i] objectAtIndex:secondTileColumn] moveTileDown];
          }
  </code></pre>
  
  <p>Any idea?</p>