I am showing data in a UITableView with a thumbnail image. Initially, when the cell is clicked on, I would reload the image from the server which would take additional time, resources, and memory. Instead of doing this, I thought of passing a pointer of the thumbnail image to the view that will be on screen and display it immediately, instead of having to redownload it. However, I am running into a problem – nothing loads when I set the imageView on the new view to the old image. Here is my code:
This is in my UITableView Class:
CustomCell *cell = (CustomCell *)[tableView cellForRowAtIndexPath:indexPath];
NewsViewController *newsViewController = [[NewsViewController alloc] initWithNibName:@"NewsViewController" bundle:nil dictionary: dict type:d numberOfPages:1 image: cell.imageView.image];
NewsViewController.m:
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil dictionary:(NSDictionary *)dict type:(NSInteger)type numberOfPages:(NSInteger)pages image:(UIImage *)image{
self = [super initWithNibName:@"NewsViewController" bundle:Nil];
if (self) {
newsText = [dict objectForKey:@"content"];
newsTitle = [dict objectForKey:@"title"];
newsDate = [dict objectForKey:@"pub_date"];
d = type;
numberOfPages = pages;
imageURL = [[NSMutableArray alloc] initWithCapacity:numberOfPages];
mainImage = [[UIImage alloc] init];
mainImage = image;
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
labelBody.text= newsText;
titleView.text = newsTitle;
date.text = newsDate;
if (numberOfPages == 1) {
imageScrollView.contentSize = CGSizeMake(320, 303);
pageControl.numberOfPages = 1;
CustomImageView *customImageView = [[CustomImageView alloc] initWithFrame:imageScrollView.bounds];
[imageScrollView addSubview:customImageView];
customImageView.imageView.image = mainImage;
}
}
NewsViewController.h
#import <UIKit/UIKit.h>
#import "AdWhirlView.h"
#import "AdWhirlDelegateProtocol.h"
@class Reachability;
@interface NewsViewController : UIViewController<AdWhirlDelegate, UIScrollViewDelegate>{
AdWhirlView *adView;
IBOutlet UILabel *labelBody;
IBOutlet UILabel *titleView;
IBOutlet UILabel *subTitle;
IBOutlet UILabel *date;
IBOutlet UIScrollView *scrollView;
IBOutlet UIScrollView *imageScrollView;
IBOutlet UIImageView *backgroundImage;
IBOutlet UIImage *mainImage;
IBOutlet UIPageControl *pageControl;
NSInteger numberOfPages;
NSMutableArray *imageURL;
}
@property(nonatomic,retain)AdWhirlView *adView;
@property (nonatomic, retain) NSMutableArray *imageURL;
@property (nonatomic, retain) IBOutlet UIPageControl *pageControl;
@property (nonatomic, retain) IBOutlet UIScrollView *imageScrollView;
@property (nonatomic, weak) IBOutlet UIImageView *backgroundImage;
@property (nonatomic, retain) IBOutlet UIImageView *imageView;
@property (nonatomic, retain) IBOutlet UIScrollView *scrollView;
@property (nonatomic, retain) IBOutlet UIImage *mainImage;
@property (nonatomic, strong) NSString *newsText;
@property (nonatomic, strong) NSString *newsTitle;
@property (nonatomic, strong) NSString *newsDate;
@property (nonatomic, assign) NSInteger numberOfPages;
@property (nonatomic, strong) IBOutlet UILabel *titleView;
@property (nonatomic, strong) IBOutlet UILabel *labelBody;
@property (nonatomic, strong) IBOutlet UILabel *subTitle;
@property (nonatomic, strong) IBOutlet UILabel *date;
@property (nonatomic, retain) Reachability* internetReachable;
@property (nonatomic, assign) BOOL internetActive;
-(void) checkNetworkStatus:(NSNotification *)notice;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil dictionary: (NSDictionary *)dict type:(NSInteger)type numberOfPages:(NSInteger) pages image:(UIImage *)image;
- (BOOL)checkInternet;
- (void)doStuff;
- (IBAction)ad;
@end
I am using mainImage as a (UIImage *) and trying to replace the image in my customImageView class with the main Image but nothing is showing up. What am I missing here?
I guess you’d like to build some sort of caching mechanism for your UIImageView. One of the easiest ways to get all of this working is by making use of the AFNetworking library.
AFNetworking extends UIImageView with some extra methods for loading images from remote sources. AFNetworking has caching build-in, no need to reinvent the wheel 🙂
Take a look on the following sites: