Gestures not reaching custom view in iOS7 when tableview has a background view

[atetlaw]

Hi, here's curly one.

It appears that if you insert the empty view beneath the UITableViewWrapperView in the tableview's hierarchy, gestures don't work in iOS7.

Normally it's fine, since inserting the empty view at index 1 puts it above this view (UITableViewWrapperView view is usually at index 0)

But if you've set a background view for your tableview, the background view is at index 0 and the UITableViewWrapperView is at index 1. Thus the empty view is inserted beneath the UITableViewWrapperView view.

This is only a problem in iOS7. In iOS8 inserting the empty view beneath the UITableViewWrapperView view doesn't seem to matter, gestures still work.

Here's my solution:

if ([self isKindOfClass:[UITableView class]] && self.subviews.count > 1) {
    UITableView *tableview = (UITableView *)self;
    if (tableview.backgroundView && self.subviews.count > 2) {
       [tableview insertSubview:view atIndex:2];
   } else {
       [tableview insertSubview:view atIndex:1];
   }
}

I can submit a pull request if you think the above is not crazy.

[dzenbot]

That makes sense.
If you could make it compatible with UICollectionView too, that would be great.

So instead of [self isKindOfClass:[UITableView class]] check for [self respondsToSelector:@selector(backgroundView)]

[bartvandendriessche]

Just ran into the same issue.

Unfortunately, if the UITableView has a backgroundView and a UIRefreshControl, then index 2 is not correct and the DZNEmptyDataSetView needs to be inserted at index 3 instead.

Not sure how to best approach this without it being brittle towards the future :/

[dzenbot]

In that case, we must make sure it gets inserted at the latest index, right?

NSIndex lastIndex = self.subviews.count+1;
[self insertSubview:view atIndex:lastIndex];

[bartvandendriessche]

I would do that, but your original code specifically mentions inserting the DZNEmptyDataSetView at index 1 in case the UITableView has a header or footer.

Inserting at the last index is the same as just doing [self addSubview:view].

A hacky workaround that doesn't look for a specific classname would be something like this:

        if (!view.superview) {
            // Send the view to back, in case a header and/or footer is present
            if ([self isKindOfClass:[UITableView class]] && self.subviews.count > 1) {
                __block NSUInteger *highestIndexOfTableViewFillingSubview = 0;
                [self.subviews enumerateObjectsUsingBlock:^(UIView *subview, NSUInteger idx, BOOL *stop) {
                    if (CGRectEqualToRect(subview.bounds, self.frame)) {
                        highestIndexOfTableViewFillingSubview = idx;
                    }
                }];
                [self insertSubview:view atIndex:highestIndexOfTableViewFillingSubview+1];
            }
            else {
                [self addSubview:view];
            }
        }

But I don't really love that approach either.

Edit:
I don't know if this is an issue on iOS 6 as well, but maybe we could wrap this hierarchy code in a iOS version check ?

[bartvandendriessche]

Something like this:

if (!view.superview) {
  // Send the view to back, in case a header and/or footer is present
  if ([self isKindOfClass:[UITableView class]] && self.subviews.count > 1) {
    if (floor(NSFoundationVersionNumber) > NSFoundationVersionNumber_iOS_6_1 &&
        floor(NSFoundationVersionNumber) <= NSFoundationVersionNumber_iOS_7_1) {
      // annoying hack to work around an iOS 7 issue
      __block NSUInteger *highestIndexOfTableViewFillingSubview = 0;
      [self.subviews enumerateObjectsUsingBlock:^(UIView *subview, NSUInteger idx, BOOL *stop) {
      if (CGRectEqualToRect(subview.bounds, self.frame)) {
            highestIndexOfTableViewFillingSubview = idx;
      }
    }];
      [self insertSubview:view atIndex:highestIndexOfTableViewFillingSubview+1];
    }
    else {
      [self insertSubview:view atIndex:1];
    }
  }
  else {
    [self addSubview:view];
  }
}