title: How to use UIBezierPath in a auto layout view?
body: <p>As far as I know, views displayed by constraints don't got a frame, so what should I do when I want to draw some lines in these views? Methods like <code>moveToPoint</code> do need a <code>CGRect</code>.</p>
  
  <p>Here's my check: <code>NSLog(@"%f,%f,%f,%f",self.contentView.frame.origin.x,self.contentView.frame.origin.y,self.contentView.frame.size.width,self.contentView.frame.size.height);</code> 
  And the result is <code>0.000000,0.000000,0.000000,0.000000</code></p>
  
  <p>For more details, here's my code:</p>
  
  <pre><code>-(void)loadView
  {
      self.view = [[UIView alloc]init];
  
  
      self.titleView = [[UIView alloc]init];
      self.placesHolder = [[UIView alloc]init];
      self.contentView = [[UIView alloc]init];
  
      self.titleView.translatesAutoresizingMaskIntoConstraints = NO;
      self.placesHolder.translatesAutoresizingMaskIntoConstraints = NO;
      self.contentView.translatesAutoresizingMaskIntoConstraints = NO;
  
      self.titleView.backgroundColor = [UIColor grayColor];
      self.placesHolder.backgroundColor = [UIColor blueColor];
      self.contentView.backgroundColor = [UIColor redColor];
  
      [self.view addSubview:self.titleView];
      [self.view addSubview:self.placesHolder];
      [self.view addSubview:self.contentView];
  
      NSDictionary *timeLineViewMap = @{@"titleView":self.titleView,
                                    @"placesHolder":self.placesHolder,
                                    @"contentView":self.contentView
                                    };
  
  
      NSArray *titleHorizon = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|[titleView]|" options:0 metrics:nil views:timeLineViewMap];
      NSArray *placesHolderHorizon = [NSLayoutConstraint constraintsWithVisualFormat:@"H:|[placesHolder(==58)]-0-[contentView]|" options:0 metrics:nil views:timeLineViewMap];
      NSArray *titleVertical = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|[titleView(==58)]-0-[placesHolder]|" options:0 metrics:nil views:timeLineViewMap];
      NSArray *contentViewConstrain = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[titleView]-0-[contentView]|" options:0 metrics:nil views:timeLineViewMap];
  
  
      [self.view addConstraints:titleHorizon];
      [self.view addConstraints:placesHolderHorizon];
      [self.view addConstraints:titleVertical];
      [self.view addConstraints:contentViewConstrain];
  }
  </code></pre>