Problem updating UITableViewCells when rotating UITableView

Question

I have a UILabel in a custom UITableViewCell that gets resized when the device is rotated. The text in this label needs to be recalculated after the rotation because I am cutting it down to size and appending some text at the end.

E.g. the datamodel has: "This is a run-on sentence that needs to stop."

In portrait mode it becomes "This is a run-on sent... more"

In landscape mode it becomes "This is a run-on sentence that... more"

From (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation I am able to access the visible UITableViewCells and update the descriptions.

The problem seems to be that there are UITableViewCells that are cached but I can't get to. When I scroll the UITableView after a rotation, one or two cells that are below the visible area after the rotation don't have the correct text in the label. So they haven't been rendered via (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath - but they weren't returned by [tableView visibleCells] (or via looping through all views returned via [tableView subViews]).

I've tried to access the "extra" cells via this method:

for (int index=max + 1; index < max + 3 && index < [cellTypes count]; index++) {
    NSIndexPath *updatedPath = [NSIndexPath indexPathForRow:index inSection:0];
    UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:updatedPath];
    if (cell == nil) { continue; }
    [self updateCellForRotate:cell forRow:index];
}

(where max is the biggest row returned from visibleCells) but cell is always nil.

Is there anyway to flush the cache of UITableViewCells so that they don't get re-used? Or to access them so I can update them?

Thanks!

Answer 1

When you create the cell in cellForRowAtIndexPath:, add it to an array. Then, loop through the array, updating the text as necessary.

Hope this helps,
jrtc27

EDIT:

You say they are custom cells - could you not update your text in your UITableViewCell subclass?

Answer 2

Firstly, to reload all of your table cells use [self.tableView reloadData]

Secondly, add the line of code that is responsible for the shrinking inside the (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath method.

Example:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    //Some identifier and recycling stuff

    if (UIInterfaceOrientationIsPortrait(self.interfaceOrientation)) {
        //Make labels smaller
    }
    else {
        //Make them bigger
    }
}

Or you can just call your updateCellForRotate:forRow: method when making them. But I'm not sure how that function works, so I can't be too specific.