点击图片crash

[hxming2919]

• (void)photoClick:(UITapGestureRecognizer *)recognizer
  {
  _scrollView.hidden = YES;
  _willDisappear = YES;

  SDBrowserImageView *currentImageView = (SDBrowserImageView *)recognizer.view;
  NSInteger currentIndex = currentImageView.tag;

  UIView *sourceView = self.sourceImagesContainerView.subviews[currentIndex];
  CGRect targetTemp = [self.sourceImagesContainerView convertRect:sourceView.frame toView:self];

  UIImageView *tempView = [[UIImageView alloc] init];
  tempView.contentMode = sourceView.contentMode;
  tempView.clipsToBounds = YES;
  tempView.image = currentImageView.image;
  CGFloat h = (self.bounds.size.width / currentImageView.image.size.width) * currentImageView.image.size.height;

  if (!currentImageView.image) { // 防止 因imageview的image加载失败 导致 崩溃
  h = self.bounds.size.height;
  }

  tempView.bounds = CGRectMake(0, 0, self.bounds.size.width, h);
  tempView.center = self.center;

  [self addSubview:tempView];

  _saveButton.hidden = YES;

  [UIView animateWithDuration:SDPhotoBrowserHideImageAnimationDuration animations:^{
  tempView.frame = targetTemp;
  self.backgroundColor = [UIColor clearColor];
  _indexLabel.alpha = 0.1;
  } completion:^(BOOL finished) {
  [self removeFromSuperview];
  }];
  }

这里会导致crash
UIView *sourceView = self.sourceImagesContainerView.subviews[currentIndex];

场景：

sourceImagesContainerView的subviews的count 小于 图片数组的时候