NSThread共享對象問題

我得到一個「EXC_BAD_ACCESS」，但只是不能解決爲什麼，任何幫助將是巨大的 - 預先感謝您。NSThread共享對象問題

的用戶拍照時，我想要做一些處理就可以在另一個線程...

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info 
{ 

... 

NSString *uid = [Asset stringWithUUID]; 

[_imageQueue setObject:img forKey:uid]; 

[NSThread detachNewThreadSelector:@selector(createAssetAsyncWithImage:) 
       toTarget:self 
       withObject:uid]; 
}

然後新線程

-(void) createAssetAsyncWithImage:(NSString *)uid { 

NSAutoreleasePool * pool =[[NSAutoreleasePool alloc] init]; 

if ([_imageQueue objectForKey:uid]) { 
Asset *asset = [Asset createAssetWithImage:[_imageQueue objectForKey:uid]]; 

asset.uid = uid; 

[self performSelectorOnMainThread:@selector(asyncAssetCreated:) 
     withObject:asset 
     waitUntilDone:YES]; 

} 

[pool release]; 
}

其中要求

+(Asset *)createAssetWithImage:(UIImage *)img 
    { 
    .... 

    UIImage *masterImg = [GraphicSupport createThumbnailFromImage:img pixels:img.size.height/2]; 
    .... 

    return newAsset; 
    }

然後這是我不斷得到的BAD_ACCESS

+(UIImage *)createThumbnailFromImage:(UIImage *)inImage pixels:(float)pixels{ 

CGSize size = image.size; 
CGFloat ratio = 0; 

if (size.width > size.height) { 

    ratio = pixels/size.width; 
} 
else { 
    ratio = pixels/size.height; 
} 

CGRect rect = CGRectMake(0.0, 0.0, ratio * size.width, ratio * size.height); 

UIGraphicsBeginImageContext(rect.size); 

//NSAssert(image,@"image NULL"); 

[image drawInRect:rect]; 

return UIGraphicsGetImageFromCurrentImageContext(); 
}

它的形象，是給我所有的投訴...

我在做什麼錯？

很多感謝

來源

2010-03-31 Chris

在createThumbnailFromImage，不應圖像是inImage？ – DyingCactus 2010-03-31 18:29:32