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UITableView don't float section headers

Is it possible to not float the section headers for a UITableView with style UITableViewStylePlain?

I'm building AcaniChat, an open-source version of iPhone's native Messages app, and I want to make the timestamps section headers, but they shouldn't float.

I know that section headers don't float for table views of style UITableViewStyleGrouped, but that style looks less like what I'm going for. Should I just use that style and restyle the table view to make it look how I want?

I might do that if I can figure out how to make https://stackoverflow.com/questions/65开发者_开发百科64712/nsfetchedresultscontroller-nsdate-section-headers.


The interesting thing about UITableViewStyleGrouped is that the tableView adds the style to the cells and not to the TableView.

The style is added as backgroundView to the cells as a class called UIGroupTableViewCellBackground which handles drawing different background according to the position of the cell in the section.

So a very simple solution will be to use UITableViewStyleGrouped, set the backgroundColor of the table to clearColor, and simply replace the backgroundView of the cell in cellForRow:

cell.backgroundView = [[[UIView alloc] initWithFrame:cell.bounds] autorelease];


I guess either you will have to use two kinds of custom tableCells or skip the tableview entirely and work on a plain scrollview to achieve this kind of style.


This can now be done in two quick and easy steps (iOS 6 only):

  1. Change your UITableView style to UITableViewStyleGrouped. (You can do this from Storyboard/NIB, or via code.)

  2. Next, set your tableview's background view to a empty view like so [in either a method such as viewDidAppear or even in the cellForRow method (though I would prefer the former)].

yourTableView.backgroundView = [[UIView alloc] initWithFrame:listTableView.bounds];

Voila, now you have your table view - but without the floating section headers. Your section headers now scroll along with the cells and your messy UI problems are solved!

This works because UITableViewStyleGrouped seems to now work by adding a background view to a plain UITableView, but without the floating section headers. [N.B. Earlier to iOS 6, individual background images were added to UITableViewCell's.]

Do try this out and let me know how it goes. Happy coding :)

EDIT: for iOS 7, simply change the table view style to 'UITableViewStyleGrouped' and change the view's tint color to 'clear color'.


You can achieve this by putting the headers into their own sections. First double your number of sections. Then for the even-numbered sections, return your header as the header and zero as the number of rows. For the odd-numbered sections, return nil for the header.

Assuming you're using an NSFetchedResultsController, it would look something like this:

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return self.fetchedResultsController.sections.count * 2;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
    if ((section % 2) == 0)
    {
        section /= 2;

        id<NSFetchedResultsSectionInfo> sectionInfo = self.fetchedResults.sections[section];
        return sectionInfo.name;
    }
    else
    {
        return nil;
    }
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    if ((section % 2) == 0)
    {
        return 0;
    }
    else
    {
        section /= 2;

        id<NSFetchedResultsSectionInfo> sectionInfo = self.fetchedResults.sections[section];
        return sectionInfo.numberOfObjects;
    }
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    if ((indexPath.section % 2) == 0)
    {
        return nil;
    }
    else
    {
        indexPath = [NSIndexPath indexPathForRow:indexPath.row inSection:indexPath.section/2];
        id object = [self.fetchedResultsController objectAtIndexPath:indexPath];

        // configure your cell here.
    }
}
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