Delete selected images from a row containing multiple cells in UITableView - ios

Question

I have a UITableView containing list of images, each row contains 4 UITableViewCell,
the user can select multiple images (selection is by hiding and showing an overlay image on the cell)
what i want to do is when user click delete button is to remove the selected image from my table.
Here is some of the code:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
static NSString *CellIdentifier = #"Cell";
ThumbnailImageCell *cell = (ThumbnailImageCell *)[tableView dequeueReusableCellWithIdentifier:#"Cell"];
if (cell == nil)
{
cell = [[[ThumbnailImageCell alloc] initWithManagedImages:[self imagesForIndexPath:indexPath] reuseIdentifier:CellIdentifier] autorelease];
}
else
{
[cell setImages:[self imagesForIndexPath:indexPath]];
}
return cell;}
-(NSArray*)imagesForIndexPath:(NSIndexPath*)_indexPath {
int index = (_indexPath.row*4);
int maxIndex = (_indexPath.row*4+3);
if(maxIndex < [self.imagesArray count]) {
return [NSArray arrayWithObjects:[self.imagesArray objectAtIndex:index],
[self.imagesArray objectAtIndex:index+1],
[self.imagesArray objectAtIndex:index+2],
[self.imagesArray objectAtIndex:index+3],
nil];
}
else if(maxIndex-1 < [self.imagesArray count]) {
return [NSArray arrayWithObjects:[self.imagesArray objectAtIndex:index],
[self.imagesArray objectAtIndex:index+1],
[self.imagesArray objectAtIndex:index+2],
nil];
}
else if(maxIndex-2 < [self.imagesArray count]) {
return [NSArray arrayWithObjects:[self.imagesArray objectAtIndex:index],
[self.imagesArray objectAtIndex:index+1],
nil];
}
else if(maxIndex-3 < [self.imagesArray count]) {
return [NSArray arrayWithObject:[self.imagesArray objectAtIndex:index]];
}
return nil;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return ceil([self.imagesArray count] / 4.0);
}
What I tried to do is the following but without any success till now
-(void)finishDeleting{
int countOfDeletedThread;
[self setEditing:YES animated:YES];
[self.tableView beginUpdates];
NSMutableIndexSet *mutableIndexSet = [[NSMutableIndexSet alloc] init];
NSMutableArray *indexToDelete = [[NSMutableArray alloc] init];
NSIndexPath *indexPath ;
for(ThumbnailImage *thumbnailImage in self.imagesArray)
{
if([thumbnailImage selected])
{
countOfDeletedThread = countOfDeletedThread+1;
indexPath = [NSIndexPath indexPathForRow:countOfDeletedThread inSection:0];
[indexToDelete addObject:indexPath];
[mutableIndexSet addIndex:indexPath.row];
}
}
[self.imagesArray removeObjectsAtIndexes:mutableIndexSet];
[self.tableView deleteRowsAtIndexPaths:indexToDelete withRowAnimation:UITableViewRowAnimationFade];
[indexToDelete release];
[mutableIndexSet release];
[self.tableView endUpdates];
[self.tableView setEditing:NO animated:YES];
[self.tableView reloadData];
[CATransaction flush];}
Any help please? I am stuck for 2 days and don't know what to do.
Thank you.

Answer 1

If I understand it correctly, you have 4 UIImageViews per table row, not
4 UITableViewCells. That means if you delete a subset of the images, the remaining
images will "reflow" across all rows. Therefore it does not make sense to use
beginUpdates/deleteRowsAtIndexPaths/endUpdates. You probably should just
remove the selected images from the data source array self.imagesArray,
call [self.tableView reloadData].
Removing the selected images from the array can be slightly simplified to
NSIndexSet *indexSet = [self.imagesArray indexesOfObjectsPassingTest:^BOOL(ThumbnailImage *thumbnailImage, NSUInteger idx, BOOL *stop) {
return [thumbnailImage selected];
}];
[self.imagesArray removeObjectsAtIndexes:indexSet];
Note that UICollectionView (available since iOS 6) might be better suited to display
multiple images per row.