UITableviewcells unwanted animation from the side - ios

Question

I am trying to animate a tableview on a view that uses autolayout.
I am able to animate the tableview fine but for some reason there is a unwanted sideways animation when doing so.
The first animation closes the top tableview works fine. However the second animation that extends the bottom tableview is the one that has the sideways movement. Here is my code:
[self.dataSelectionTable layoutIfNeeded];
[self.comparatorSelectionTable layoutIfNeeded];
[UIView animateWithDuration:0.5 animations:^{
self.dataSelectionTableHeight.constant = 44;
[self.view layoutIfNeeded]; and then captures all of the frame changes
} completion:^(BOOL finished){
[UIView animateWithDuration:0.5 animations:^{
self.comparatorSelectionTableHeight.constant = 200;
[self.view layoutIfNeeded];
}];
}];
I have tried changing the animation type but that does not seem to work.
Here is a link to a gif that shows the unwanted sideways animation: http://makeagif.com/YubmP2
Edit
Here is the code for populating the tableviews:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
cell.textLabel.numberOfLines = 0;
cell.textLabel.font = [UIFont fontWithName:#"Helvetica" size:13.0];
}
if (tableView == self.dataSelectionTable) {
cell.textLabel.text = self.dataSelectionTitles[indexPath.row];
}
else {
cell.textLabel.text = [self.comparatorList[indexPath.row] name];
}
return cell;
}

Answer 1

I tried to duplicate your problem, but got slightly different results. Instead of a sideways movement, I got a downward movement of the label within the cell (but only the first time I did the animation).
I noticed that if I set the table view's height constraint's constant value to 0 in viewDidLoad, cellForRowAtIndexPath was not called until I did the expansion, so I'm guessing that some of the laying out of views of the table view wasn't happening until then.
I fixed the problem by setting the alpha value of the table view to 0 in IB, and set its height to 400 (the value I wanted after expansion). Then in viewDidAppear, I did this,
-(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
self.heightCon.constant = 0;
self.tableView.alpha = 1;
}
This caused the table's data source methods to run right away, but with the table view not visible. Now when I animated the expansion, I didn't get any movement of the label within the cell.