At the moment I got my main tableview with cells, which are loaded from a XML and filled up. After that I can click on one cell and a detailview is loaded(xib file, loaded through code in the main tableview). On the detailview I can click a download button and some files are downloaded asynchron to the documents folder. Then I pop the view down and I see again my tableview.

My idea now is to see the progress of the download in the tableview cell. I set up a uiprogressview on every cell, which is hidden on default. I now want to see the progress bar when I start the download. How can I do that? 

I tried something with performSelectorOnMainThread and a selector, which change the progress of my selected cell(which I assign in the main tableview). Seems to be a bad idea - didnt work.

Some ideas how to do that?



EDIT2: Some piece of code of my solution, ATTENTION! This is not the real code, I deleted a lot of lines for inserting here. There arent all releases etc. I think the solution is really dirty, but I didnt found a better solution for me...

Some important things:


cellDownloading: Array which knows
every cell which is downloading at
the moment
progressDictionary: Knows the progress of every cell
cellDictionary: Knows every cell, filled up in the cellsForRowAtIndexpath delegte of the tableview


I also cant copy the whole code, because there is a lot which have nothing to do with the whole process, but I give you the important steps.
My cells are created through parsing a xml, so every cell has got a setId in my case.

//////////////////
// Downloader.mm
//////////////////

method to download asynchron

-(void)startAsynchronousDownload:(NSString*)path{    

// generate notification
NSMutableDictionary *userInfo = [[NSMutableDictionary alloc] init];
NSNumber *tmpSetId = [NSNumber numberWithInteger:setId];

[userInfo setObject:tmpSetId forKey:@"setId"];

NSNotification* notification = [NSNotification notificationWithName:@"downloadStackNotification" object:self userInfo:userInfo];  
[[NSNotificationCenter defaultCenter] postNotification:notification];  

// add some infos...
NSMutableDictionary *dictionary = [[NSMutableDictionary alloc] init];
[dictionary setObject:tmpSetId forKey:@"setId"];
// perhaps more here

// asynchronous download handling
NSOperationQueue *queue = [NSOperationQueue alloc] init];
NSInvocationOperation *operation = [[NSInvocationOperation alloc] initWithTarget:self selector:@selector(downloadImagesWithDictionary:) object:dictionary];

// release
[operation release];
[dictionary release];
[userInfo release];
}


In my example the selector downloadImagesWithDictionary downloads some images, for every downloaded image I send a notification. Every stack of images have a setId in my case.

[...]
    NSMutableDictionary *userInfo = [[NSMutableDictionary alloc] init];
    NSNumber *sliceCounter = [NSNumber numberWithInt:i];
    NSNumber *amount = [NSNumber numberWithInt:amountOfImages];
    NSNumber *tmpSetId = [NSNumber numberWithInteger:setId];

    [userInfo setObject:sliceCounter forKey:@"actualImage"];
    [userInfo setObject:amount forKey:@"allImages"];
    [userInfo setObject:tmpSetId forKey:@"setId"];
    NSNotification* notification = [NSNotification notificationWithName:@"downloadSliceNotification" object:self userInfo:userInfo];  
    [[NSNotificationCenter defaultCenter] postNotification:notification ];  
[...]


////////////////////////////
// TableViewController.mm
////////////////////////////

Now we need to get the notifications to update our tableview

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(downloadSliceNotification:) name:@"downloadSliceNotification" object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(downloadStackNotification:) name:@"downloadStackNotification" object:nil];


We need a cell dictionary to know all indexpath of our existing tableview cells.
Fill them in the cellForRowAtIndexPath delegate

[cellDictionary setObject:indexPath forKey:[NSString stringWithFormat:@"%d",cellSetId]];


Now we create the handler to do somehting if we got a notification
First the handler if the download starts
I have got a progress dictionary which knows every progress of every cell
I can identify every cell by the setId - perhaps u have to change that a little bit

- (void)downloadStackNotification:(NSNotification*)notification {  
NSDictionary *userInfo = [notification userInfo];
NSNumber *setId = [userInfo objectForKey:@"setId"];

NSNumber *progress = [NSNumber numberWithInt:0];    
[progressDictionary setObject:progress forKey:[setId stringValue]];

// add cell to downloadlist
[cellDownloading addObject:[setId stringValue]];


} 

Now for every download step(in my case one image). 
Calculate process and update the dictionary, get the cell to update the progress

- (void)downloadSliceNotification:(NSNotification*)notification {  
NSDictionary *userInfo = [notification userInfo];
NSNumber *sliceCounter = [userInfo objectForKey:@"actualImage"];
NSNumber *amount = [userInfo objectForKey:@"allImages"]; 
NSNumber *setId = [userInfo objectForKey:@"setId"]; 

NSNumber *progress = [NSNumber numberWithFloat:(100/[amount floatValue])*[sliceCounter floatValue]];      

[progressDictionary setObject:progress forKey:[setId stringValue]];
NSIndexPath* indexPath = [cellDictionary objectForKey:[setId stringValue]];

CustomServerCell* cell = (CustomServerCell*)[self.tableView cellForRowAtIndexPath:indexPath];
NSMutableDictionary *downloadData = [[NSMutableDictionary alloc] init];
[downloadData setObject:cell forKey:@"cell"];
[downloadData setObject:sliceCounter forKey:@"actualImage"];
[downloadData setObject:amount forKey:@"allImages"];

[self performSelectorOnMainThread:@selector(updateProgressWithDictionary:) withObject:downloadData waitUntilDone:NO];
} 


Update the cell

-(void)updateProgressWithDictionary:(NSMutableDictionary*)downloadData {

CustomServerCell* cell = (CustomServerCell*)[downloadData objectForKey:@"cell"];
NSNumber *sliceCounter = [downloadData objectForKey:@"actualImage"];
NSNumber *amount = [downloadData objectForKey:@"allImages"];

cell.progressView.hidden = FALSE;
NSNumber *tmpProgress = [progressDictionary objectForKey:[NSString stringWithFormat:@"%d",cell.progressView.tag]];
cell.progressView.progress = [tmpProgress floatValue]/100;
cell.statusLabel.text = [NSString stringWithFormat:@"download slice %d / %d",[sliceCounter integerValue],[amount integerValue]];


}


Question: How to extract name/data from database and use it as my folder name which is created dynamically in asp.net c# using server.MapPath()?
Answer: As far as I know, you can't do one statement to create folder and subfolders because you need the folder to be created first.

You have all of the code you need, you just need to repeat it.  Check to see if the main folder (username) exists.  If it doesn't create it, if it does, check to see if the subfolder exists.  If it doesn't, create it. 

Just work through that logic and you'll be set.