Disable TableView cells - ios

Question

How can I disable all cells, except the first 3 cells of a UITableView?
This returns nil if one of the disabled cells is selected:
- (NSIndexPath *)tableView:(UITableView *)tableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath {
if ( indexPath.row >= 3 ) {
[[self.tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:2 inSection:0]] setAlpha:0.5];
return nil;
}
return indexPath; }
How can I make the disabled cells "visible"?
This works, but I only on start up, because the indexPath of every cell changes while scrolling (reuse cells):
for(int i = 3; i <= 100; i++) {
[[self.tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0]] setAlpha:0.5];
}

Answer 1

You can disable the cells by setting the selectionStyle property, see the code below:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = ...
cell.selectionStyle = UITableViewCellSelectionStyleNone;
}
Another way to disable the cell selection is by disabling the user interaction of the cell. See the code below:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = ...
cell.userInteractionEnabled = NO;
}
Enjoy. :)

Answer 2

It's best to set the opacity of the disabled cells in tableView:cellForRowAtIndexPath:. As #Parcs correctly says in their answer, you can also set userInteractionEnabled for the disabled cells to NO there.
You can just ignore the taps on inactive cells in tableView:didSelectRowAtIndexPath:.

Answer 3

Since the other answer providing code is outdated only showing how it's done in obj-c, here is a swift solution.
To disable a cell you need to set the isUserInteractionEnabled flag of a UITableViewCell to false.
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// dequeue cell
...
cell.isUserInteractionEnabled = false
return cell
}
For subclasses of UITableViewCell you probably also want to alter the appearance of the now disabled cell. You can do so by overriding the property to run additional code when the flag gets set.
override var isUserInteractionEnabled: Bool {
didSet {
super.isUserInteractionEnabled = isUserInteractionEnabled
// additional code to change text colors for example
}
}