Custom UITableViewCell with Progress Bar download update

Question

I am trying to update a each table cell with progress bar loading, but I am stuck. I created a custom cell for a table view with these properties:

@interface         


        

Answer 1

You should keep the value of (double)totalBytesWritten / (double)totalBytesExpectedToWrite in OFPVideoDetails (add one property "progress" in OFPVideoDetails).

Then reload the cell in - (void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didWriteData:(int64_t)bytesWritten totalBytesWritten:(int64_t)totalBytesWritten totalBytesExpectedToWrite: (int64_t)totalBytesExpectedToWrite

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    OFPTableCell *cell = [self.tableViewCache dequeueReusableCellWithIdentifier:@"Cell"];
    OFPVideoDetails *vd = [someArray objectAtIndex:indexPath.row];
    cell.textLabel.text=vd1;
    cell.detailTextLabel.text=vd2;
    CGSize size = {65,53};
    cell.imageView.image =[self imageWithImage:[UIImage       imageWithContentsOfFile:vd.imageUrl] scaledToSize:size];
    cell.progressView.progress = vd.progress;
    cell.delegate = self;
    return cell;
}

Answer 2

It's very bad practise to call method tableView:cellForRowAtIndexPath:directly, becuase the cell may not exist at the same moment and it may be a cause of the bug you have.

Basically you should do this in another way: add an array of double:

double progressValues[30]; // 30 is the count of rows on your tableView, you can set the size dynamically

and use it like this:

- (void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didWriteData:(int64_t)bytesWritten 
totalBytesWritten:(int64_t)totalBytesWritten totalBytesExpectedToWrite:
(int64_t)totalBytesExpectedToWrite
{
  dispatch_async(dispatch_get_main_queue(), ^{
  NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
  OFPTableCell *cell = (OFPTableCell*)[self tableView:self.tableViewCache    cellForRowAtIndexPath:indexPath];
  progressValues[indexPath.row] = (double)totalBytesWritten /  (double)totalBytesExpectedToWrite;
  [self.tableViewCache reloadData];
});
}

and in the dataSource method just add this string:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    //... your code...
    cell.progressView.progress = progressValues[indexPath.row];
    // ...
    return cell;
}

Answer 3

For Swift 4.2

  func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didWriteData bytesWritten: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64) {

          DispatchQueue.main.async(execute: {
            let indexPath = IndexPath(row: 0, section: 0)
            let cell = self.tableView(self.tableViewCache, cellForRowAt: indexPath) as? OFPTableCell
            progressValues[indexPath.row] = Double(totalBytesWritten) / Double(totalBytesExpectedToWrite)
            self.tableViewCache.reloadData()
        })
    }