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2721

answers:

2

I would like to completely reset the scroll position of a UITableView, so that every time I open it, it is displaying the top-most items. In other words, I would like to scroll the table view to the top every time it is opened.

I tried using the following piece of code, but it looks like I misunderstood the documentation:

- (void)viewWillAppear:(BOOL)animated {
    [tableView scrollToNearestSelectedRowAtScrollPosition:UITableViewScrollPositionTop animated:NO];
}

Is this the wrong approach here?

+4  A: 

The method you're using scrolls to (as the method name implies) the nearest selected row. In many cases, this won't be the top row. Instead, you want to use either

scrollToRowAtIndexPath:atScrollPosition:animated:

or

selectRowAtIndexPath:animated:scrollPosition:

where you use the index path of the row you want to scroll to. The second method actually selects a row, the first method simply scrolls to it.

August
These didn't work for me with iOS 4.0 during the start of an animation sequence. I had to use scrollRectToVisible:animated:
chrish
+6  A: 

August got the UITableView-specific method. Another way to do it is:

[tableView scrollRectToVisible:CGRectMake(0, 0, 1, 1) animated:NO];

This method is defined in UIScrollView, the parent class to UITableView. The above example tells it to scroll to the 1x1 box at 0,0 - the top left corner, in other words.

Mike McMaster
This is actually a pretty neat way of doing it because you don't need to worry about whether your table is empty or not. I had a nasty crash going to NSIndexPath (0,0) when there were no records to display.
Stephen Darlington
Thank you!!! Great tip!
isaaclimdc