IOS - DrawRect图像

Question

我有一个UIImage，我想绘制在UILabel，从json图像加载。

我想在绘制之前保存图像。

我已经加载图像，但我不画它，我想我保存了图像问题。

这里是我的代码：

- (void)createDirectory { 

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 
    itemsFilename = [[NSString alloc] initWithString:[documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"listEPG"]]]; 
    thumbsFilename = [[NSString alloc] initWithString:[documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"listImage"]]]; 
    _itemsNames = [[NSMutableArray alloc] initWithContentsOfFile:itemsFilename]; 
    images = [[NSMutableDictionary alloc] initWithContentsOfFile:thumbsFilename]; 
    imagesOperations = [[NSOperationQueue alloc] init]; 
    [imagesOperations setMaxConcurrentOperationCount:1]; 

    if (images == nil) { 
     images = [[NSMutableDictionary alloc] init]; 
    } 
} 


- (void)drawRect:(CGRect)rect { 

    for(int i = 0;i<10;i++) { 
     NSString* imageUrl= [NSString stringWithFormat:@"%@",[[[data objectAtIndex:i] objectForKey:@"Channel"] objectForKey:@"Image"]]; 

     UIImage *imgLogo = [self setImage:imageUrl]; 
     NSLog(@"%@",imgLogo); 
     [imgLogo drawInRect:CGRectMake(0,y_lblLogo,70.f,30.f)]; 
    } 
} 

- (UIImage *) setImage:(NSString *)theUrl { 
    //NSLog(@"%@",theUrl); 
    id userImage = [images objectForKey:theUrl]; 

    if(userImage == nil) { 
     [images setObject:[NSNull null] forKey:theUrl]; 
     GetImage *op = [[GetImage alloc] initWithTheURL:theUrl target:self action:@selector(getImage:)]; 
     NSLog(@"%@",op);  //[imagesOperations addOperation:op]; 
    } else if ([userImage isKindOfClass:[NSData class]]) { 
     return [UIImage imageWithData:userImage]; 
    } 
    return [UIImage imageNamed:@""]; 
} 

- (void) getImage:(NSDictionary *)info { 

    NSString* url = [info objectForKey:@"url"]; 
    id image = [info objectForKey:@"image"]; 
    [images setObject:UIImageJPEGRepresentation(image, 0.5) forKey:url]; 
    [images writeToFile:thumbsFilename atomically:YES]; 
    NSMutableSet *filepathsSet = [[NSUserDefaults standardUserDefaults] objectForKey:@"filePathLogoChannel"]; 
    [filepathsSet setByAddingObject:thumbsFilename]; 
    [[NSUserDefaults standardUserDefaults] setObject:filepathsSet forKey:@"filePathLogoChannel"]; 
} 

Answer 1

变化

id image = [info objectForKey:@"image"]; 
[images setObject:UIImageJPEGRepresentation(image, 0.5) forKey:url]; 
[images writeToFile:thumbsFilename atomically:YES]; 

到

UIImage *image = (UIImage *)[info objectForKey:@"image"]; 
NSData *imageData = UIImageJPEGRepresentation(image, 0.5); 
[imageData writeToFile:thumbsFilename atomically:YES];