[[ZFDownloadManager sharedInstance] download:urlString progress:^(CGFloat progress, NSString *speed, NSString *remainingTime, NSString *writtenSize, NSString *totalSize) {
            dispatch_async(dispatch_get_main_queue(), ^{
				// insert code here
            });
 } state:^(DownloadState state) {}];

#pragma mark - ZFDownloadDelegate

- (void)downloadResponse:(ZFSessionModel *)sessionModel
{
    if (self.downloadObjectArr) {
        // 取到对应的cell上的model
        NSArray *downloadings = self.downloadObjectArr[1];
        if ([downloadings containsObject:sessionModel]) {
            
            NSInteger index = [downloadings indexOfObject:sessionModel];
            NSIndexPath *indexPath = [NSIndexPath indexPathForRow:index inSection:1];
            __block ZFDownloadingCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
            __weak typeof(self) weakSelf = self;
            sessionModel.progressBlock = ^(CGFloat progress, NSString *speed, NSString *remainingTime, NSString *writtenSize, NSString *totalSize) {
                dispatch_async(dispatch_get_main_queue(), ^{
                    cell.progressLabel.text   = [NSString stringWithFormat:@"%@/%@ (%.2f%%)",writtenSize,totalSize,progress*100];
                    cell.speedLabel.text      = speed;
                    cell.progress.progress    = progress;
                    cell.downloadBtn.selected = YES;
                });
            };
            
            sessionModel.stateBlock = ^(DownloadState state){
                dispatch_async(dispatch_get_main_queue(), ^{
                    // 更新数据源
                    if (state == DownloadStateCompleted) {
                        [weakSelf initData];
                        cell.downloadBtn.selected = NO;
                    }
                    // 暂停
                    if (state == DownloadStateSuspended) {
                        cell.speedLabel.text = @"已暂停";
                        cell.downloadBtn.selected = NO;
                    }
                });
            };
        }
    }
}