title: 'Constant is not finite! That's illegal. constant:nan' error in Objective C
body: <p>I'm receiving the following error when I try to launch the app I'm working on. 'Constant is not finite!  That's illegal.  constant:nan'</p>
  
  <p>It's a school project clone of instagram. I'm thinking the error is in the subview or possibly in the constraints created but unfortunately I'm just not seeing the issue. </p>
  
  <pre><code>- (void) layoutSubviews {
      [super layoutSubviews];
  
       // Before layout, calculate the intrinsic size of the labels (the size they "want" to be), and add 20 to the height for some vertical padding.
      CGSize maxSize = CGSizeMake(CGRectGetWidth(self.bounds), CGFLOAT_MAX);
      CGSize usernameLabelSize = [self.usernameAndCaptionLabel sizeThatFits:maxSize];
      CGSize commentLabelSize = [self.commentLabel sizeThatFits:maxSize];
  
      self.usernameAndCaptionLabelHeightConstraint.constant = usernameLabelSize.height + 20;
      self.commentLabelHeightConstraint.constant = commentLabelSize.height + 20;
      self.imageHeightConstraint.constant = self.mediaItem.image.size.height / self.mediaItem.image.size.width * CGRectGetWidth(self.contentView.bounds);
  
      // Hide the line between cells
      self.separatorInset = UIEdgeInsetsMake(0, 0, 0, CGRectGetWidth(self.bounds));
  }
  
  NSDictionary *viewDictionary = NSDictionaryOfVariableBindings(_mediaImageView, _usernameAndCaptionLabel, _commentLabel);
  
      [self.contentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[_mediaImageView]|" options:kNilOptions metrics:nil views:viewDictionary]];
      [self.contentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[_usernameAndCaptionLabel]|" options:kNilOptions metrics:nil views:viewDictionary]];
      [self.contentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[_commentLabel]|" options:kNilOptions metrics:nil views:viewDictionary]];
  
      [self.contentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|[_mediaImageView][_usernameAndCaptionLabel][_commentLabel]" options:kNilOptions metrics:nil views:viewDictionary]];
  
  
  
      self.imageHeightConstraint = [NSLayoutConstraint constraintWithItem:_mediaImageView attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1 constant:100];
      self.imageHeightConstraint.identifier = @"Image height constraint";
  
      self.usernameAndCaptionLabelHeightConstraint = [NSLayoutConstraint constraintWithItem:_usernameAndCaptionLabel attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1 constant:100];
      self.usernameAndCaptionLabelHeightConstraint.identifier = @"Username and caption label height constraint";
  
      self.commentLabelHeightConstraint = [NSLayoutConstraint constraintWithItem:_commentLabel attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1 constant:100];
      self.commentLabelHeightConstraint.identifier = @"Comment label height constraint";
  
      [self.contentView addConstraints:@[self.imageHeightConstraint, self.usernameAndCaptionLabelHeightConstraint, self.commentLabelHeightConstraint]];
  
  
  }
  </code></pre>