Re: Copying large files with progress indicator

FROM : Mike Abdullah
DATE : Tue Aug 01 19:50:47 2006

Thanks Shawn.  I tried to get the callback system to work, but I 
couldn't persuade it :(  Does anyone have any sample code for this?

I shall also have a look at the docs like you suggest as well.

Mike.

On 1 Aug 2006, at 16:51, Shawn Erickson wrote:

>
> On Aug 1, 2006, at 8:38 AM, Mike Abdullah wrote:
>

>>
>> 10.4 only is fine for me.  I've had a look at FSCopyObjectAsync, 
>> and after a search around, found Apple's nice FSFileOperation 
>> sample code:
>>
>> http://developer.apple.com/samplecode/FSFileOperation/
>>
>> I've got a quick simple project up and running using this, 
>> however, I wonder if someone could help clarify something for me. 
>> My code is:
>>
>> - (IBAction)doCopy:(id)sender
>> {
>>     OSStatus err;
>>     FSRef  sourceFileRef, destinationDirectoryRef;
>>     
>>     // Build the parameters
>>     FSFileOperationRef fileOp = FSFileOperationCreate
>> (kCFAllocatorDefault);
>>     
>>     FSPathMakeRef((UInt8 *)[@"/Users/dev/Desktop/test.dmg" 
>> fileSystemRepresentation], &sourceFileRef, NULL);
>>     
>>     FSPathMakeRef((UInt8 *)[@"/Users/dev/Desktop/Copy/" 
>> fileSystemRepresentation], &destinationDirectoryRef, NULL);
>>     
>>     OptionBits options = kFSFileOperationDefaultOptions;
>>     
>>     
>>     // Do the copy
>>     err = FSCopyObjectAsync(fileOp, &sourceFileRef, 
>> &destinationDirectoryRef, NULL, options, NULL, 0.01, NULL);
>>     
>>     while (YES)
>>     {
>>     CFRunLoopRunInMode(kCFRunLoopDefaultMode, 5.0, true);
>>     
>>     CFDictionaryRef infoDict2;
>>     (void) FSFileOperationCopyStatus(fileOp, NULL, NULL, &err, 
>> &infoDict2, NULL);
>>     
>>     NSLog(@"%@", (NSDictionary *)infoDict2);
>>     }
>> }
>>
>> Now obviously, I need to do this in a separate thread which isn't 
>> a problem.  However, what I don't really understand is what 
>> exactly goes on with the CFRunLoopRunInMode call.  It seems that 
>> during the duration of this method, that's when a chunk of file 
>> copying is actually done, but once I stick the code in a thread, 
>> should I really use this, or is there something better?

>
> You don't actually have to do this in a separate thread. You can 
> register a callback and execute this operation on your main thread 
> (the main thread in a Cocoa application has an active runloop). You 
> will get callbacks from your main runloop as the copy progresses 
> and when it finishes.
>
> The example above is written to be run from a secondary thread and 
> doesn't leverage the callback capability (why it is running its own 
> runloop periodically).
>
> Review the docs on runloops (CFRunLoop and NSRunLoop) if you don't 
> understand what those are.
>
> -Shawn