How to detect tap on clear part of UITableView? - ios

Question

I have view controller with UITableView. Height of table view is static and == height of screen. Number of rows in table can change and sometimes it might be a situation when number of rows is less than number of rows which can be visible, so appears some clear area on bottom of table. Can i detect tap on it without gesture recognizer? Are there some delegate methods of UITableView?

Answer 1

All of the supplied answers, including the accepted answer, add a UITapGestureRecognizer to the tableView; while this will work, I've found that this gesture recognizer can interfere with row taps and triggering didSelectRowAtIndexPath in a somewhat unpredictable/nondeterministic way.
If you want to detect taps in the "blank space" as well as in rows, I highly suggest adding a background view to your table, and add the gesture recognizer there:
let tap = UITapGestureRecognizer(target: self, action: #selector(tableTapped))
self.tableView.backgroundView = UIView()
self.tableView.backgroundView?.addGestureRecognizer(tap)

Answer 2

Yes, there are delegate methods, such as:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
However, this will only tell you if a tap occurs on an existing row. If you want to capture taps on the empty space below the rows (or on a section header) you will need to use a gesture recognizer. You can do something like this:
// in viewDidLoad or somewhere similar
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tableTapped:)];
[self.tableView addGestureRecognizer:tap];
//.........
- (void)tableTapped:(UITapGestureRecognizer *)tap
{
CGPoint location = [tap locationInView:self.tableView];
NSIndexPath *path = [self.tableView indexPathForRowAtPoint:location];
if(path)
{
// tap was on existing row, so pass it to the delegate method
[self tableView:self.tableView didSelectRowAtIndexPath:path];
}
else
{
// handle tap on empty space below existing rows however you want
}
}
EDIT: for an alternative approach, consider Connor Neville's approach from his answer on this post and add the gesture recognizer to the table's background.

Answer 3

Thanks to #Stonz2, swift version:
Swift 4
let tap = UITapGestureRecognizer(target: self, action: #selector(tableTapped))
self.tableView.addGestureRecognizer(tap)
#objc func tableTapped(tap:UITapGestureRecognizer) {
let location = tap.location(in: self.tableView)
let path = self.tableView.indexPathForRow(at: location)
if let indexPathForRow = path {
self.tableView(self.tableView, didSelectRowAt: indexPathForRow)
} else {
// handle tap on empty space below existing rows however you want
}
}
Swift 3
let tap = UITapGestureRecognizer(target: self, action: #selector(tableTapped))
self.tableView.addGestureRecognizer(tap)
func tableTapped(tap:UITapGestureRecognizer) {
let location = tap.location(in: self.tableView)
let path = self.tableView.indexPathForRow(at: location)
if let indexPathForRow = path {
self.tableView(self.tableView, didSelectRowAt: indexPathForRow)
} else {
// handle tap on empty space below existing rows however you want
}
}
Swift 2:
let tap = UITapGestureRecognizer(target: self, action: #selector(tableTapped))
self.tableView.addGestureRecognizer(tap)
func tableTapped(tap:UITapGestureRecognizer) {
let location = tap.locationInView(self.tableView)
let path = self.tableView.indexPathForRowAtPoint(location)
if let indexPathForRow = path {
self.tableView(self.tableView, didSelectRowAtIndexPath: indexPathForRow)
} else {
// handle tap on empty space below existing rows however you want
}
}

Answer 4

You don't need gesture recogniser. You should impliment <UITableViewDelegate> in your ViewController.h and then add this method to your ViewController.m:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
where indexPath is index of clicked row/column.