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iOS

Posted by Gregg Mojica
Gregg Mojica
11,506 Points

Loop Through Cells in UITableView

Hey Guys!

So I'm working on a project right now involving a UITableView. I have the cells' alpha initially set to 0 and want each cell to appear about 1 second after the other. I imagine I would need to loop through the array of tableviewcells. Any ideas? Amit Bijlani

Thanks!

2 Answers

Kai Aldag
Kai Aldag
Courses Plus Student 13,560 Points

hello greg,

what I would do is when you create the cells (in cellForRowAtIndexPath) set the cells alpha to 0 then set it to one in an animation block, it should look something like this

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
    UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath];

    cell.alpha = 0;

    [UIView animateWithDuration:1 animations:^{
            cell.alpha = 1.0;
        }];
}

this is the first thing that comes to mind, let me know if it works.

Best, Kai.

Gregg Mojica
Gregg Mojica
11,506 Points

Thanks, while that does work, it's not what I'm looking for. That code makes all the cells in the tableview fade in at the same time - I need each cell to fade in about 0.5 to 1 second after the previous.

Kai Aldag
Kai Aldag
Courses Plus Student 13,560 Points

aha i thought you might say that so I thought of doing something like this

[UIView animateWithDuration:1.0
                          delay:indexPath.row
                        options:UIViewAnimationOptionAllowUserInteraction
                     animations:^{
                         cell.alpha = 1.0
                     }completion:nil];

try that and let me know if it works

Let me know if this works, Kai

Kai Aldag
Kai Aldag
Courses Plus Student 13,560 Points

this might or might not work, if it doesn't try something like

//add all cells to a mutable array called "allCells"

-(void)animationMethod{
    int i = 0;
    [UIView animateWithDuration:1.0 animations:^{
        NSIndexPath *indexPath = [[NSIndexPath alloc]initWithIndex:i];
        [self.collectionView cellForItemAtIndexPath:indexPath].alpha = 1.0;
    }completion:^{
        while (i < allCells.count) {
            i++
            NSIndexPath *otherIndex = [[NSIndexPath alloc]initWithIndex:i];
            [UIView animateWithDuration:1
                                  delay:1
                                options:UIViewAnimationOptionAllowUserInteraction
                             animations:^{
                                    [self.collectionView cellForItemAtIndexPath:otherIndex].alpha = 1.0;
                                }completion:nil];
        }
    }];
    }
}

this might work, anyways call this method once all cells are made,

Best, Kai

Gregg Mojica
Gregg Mojica
11,506 Points
Gregg Mojica
Gregg Mojica
11,506 Points

Thank you so much! The second answer works fantastic!

Kai Aldag
Kai Aldag
Courses Plus Student 13,560 Points

No problem :)