Re: progress bar on sheet

FROM : Joannou Ng
DATE : Sun Apr 10 22:34:59 2005

Hi Chuck,

The reason your progressIndicator isn't animating is because your time 
consuming task is freezing the user interface.

Use NSThread's detachNewThreadSelector:toTarget:withObject:
http://developer.apple.com/documentation/Cocoa/Reference/Foundation/
ObjC_classic/Classes/NSThread.html

Then, when your time consuming task is done, call NSObject's 
performSelectorOnMainThread:withObject:waitUntilDone:
http://developer.apple.com/documentation/Cocoa/Reference/Foundation/
ObjC_classic/Classes/NSObject.html

Cheers, Joannou.

On 2005 Apr 10, at 15:45, Chuck Soper wrote:

> Hello,
>
> I'm trying to display a custom sheet with Yes/No buttons and a 
> indeterminate progress indicator. When the user clicks Yes I need to 
> start animating the indicator and start a time consuming task. When 
> the task finishes I'd like to display an NSRunAlertPanel then make the 
> sheet go away. All of this works great without the progress indicator.
>
> I confirmed that the indicator is connecting properly with this line:
>  NSLog(@"maxValue = %d", (int) [doTaskProgress maxValue]);
> Also, I confirmed that the NSProgressIndicator instance in IB is 
> indeterminate.
>
> My source is below. Does anyone know how I can get this working? I 
> think that the fact that the sheet is modal is preventing the progress 
> bar from updating.
>
> Chuck
>
> // from interface
> IBOutlet NSPanel *    doTaskSheet;
> IBOutlet NSProgressIndicator *doTaskProgress;
>
> // from implementation
> - (IBAction)doTaskYes:(id)sender;
> {
>    doingTask = TRUE;
>    [NSApp endSheet:doTaskSheet];
> }
>
> - (IBAction)doTaskNo:(id)sender;
> {
>    [NSApp endSheet:doTaskSheet];
> }
>
>
> - (void)askToDoTaskSheetDidEnd:(NSWindow *)sheet
>    returnCode: (int)returnCode
>    contextInfo: (void *)contextInfo
> {
>  if (doingTask) {
>
>    [doTaskProgress displayIfNeeded];
>    [doTaskProgress startAnimation:nil];
>
>    //do time consuming task then display alert then remove sheet
>    [self doTimeConsumingTask];
>    NSRunAlertPanel(statusString, resultString, @"OK", nil, nil);
>
>    [doTaskProgress stopAnimation:nil];
>
>  }
>
>  doingTask = FALSE;
>  [sheet orderOut:self];
> }
>
> //display the sheet and ask user what to do
> - (void)askToDoTaskSheet
> {
>    doingTask = FALSE;
>
>  [NSApp beginSheet: doTaskSheet
>            modalForWindow: mainWindow
>            modalDelegate: self
>            didEndSelector:
>               
> @selector(askToDoTaskSheetDidEnd:returnCode:contextInfo:)
>            contextInfo: nil];
>
> }
> _______________________________________________
> Do not post admin requests to the list. They will be ignored.
> Cocoa-dev mailing list      (<email_removed>)
> Help/Unsubscribe/Update your Subscription:
> http://lists.apple.com/mailman/options/cocoa-dev/
> <email_removed>
>
> This email sent to <email_removed>