iOS 4の新機能13選＆AssetsLibraryで作る画像ビューア：SDKで始めるiPad/iPhoneアプリ開発の勘所（終）（3/4 ページ）

#import "PhotoSelectViewController.h"
    
#pragma mark Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    PhotoSelectViewController *controller = [[PhotoSelectViewController alloc] init];
    controller.delegate = self;
    controller.group = [groups objectAtIndex:indexPath.row];
    [self.navigationController pushViewController:controller animated:YES];
    [controller release];
}

#import "PhotoViewController.h"
    
@interface PhotoSelectViewController : UITableViewController<PhotoViewControllerDelegate> {
    id delegate;
    ALAssetsGroup *group;
    @private
    NSMutableArray *photos;
}
    
@property (nonatomic, assign) id delegate;
@property (nonatomic, retain) ALAssetsGroup *group;
    
@end

#import "PhotoSelectViewController.h"
    
@implementation PhotoSelectViewController
    
@synthesize delegate;
@synthesize group;
    
#pragma mark Rotation support
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    return YES;
}
    
#pragma mark View lifecycle
- (void)viewDidLoad {
    [super viewDidLoad];
    [self.navigationItem setTitle:@"フォト選択"];
    [self performSelectorInBackground:@selector(searchPhotos) withObject:nil];
}
    
- (void)searchPhotos {
    photos = [[NSMutableArray alloc] init];
    // フォトライブラリから取得した写真を「photos」に追加
    void (^assetBlock)(struct ALAsset *, NSUInteger, BOOL *) = ^(ALAsset *result, NSUInteger index, BOOL *stop) {
        if(result != nil) {
            if(![photos containsObject:result]) {
                // ALAssetのタイプが「写真」を追加
                if([[result valueForProperty:ALAssetPropertyType] isEqualToString:ALAssetTypePhoto]) {
                    [photos addObject:result];
                }
            }
        }
    };
    // フォトライブラリへアクセスし、引数のブロックを実行
    [group enumerateAssetsUsingBlock:assetBlock];
    [self.tableView reloadData];
}
 
// テーブル指定行の画像データを取得
- (UIImage *)getPhotoImage:(NSUInteger)index {
    return [UIImage imageWithCGImage:
        [[(ALAsset *)[photos objectAtIndex:index] defaultRepresentation] fullScreenImage]];
}
 
// テーブル指定行のメタデータを取得
- (NSDictionary *)getPhotoMetaData:(NSUInteger)index {
    NSDictionary *metaData = [[(ALAsset *)[photos objectAtIndex:index] defaultRepresentation] metadata];
    return [metaData objectForKey:(NSString *)kCGImagePropertyExifDictionary];
}
 
#pragma mark Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return 1;
}
 
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return [photos count];
}
 
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil)
        cell = [[[UITableViewCell alloc] initWithStyle:
            UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    UIImage *image = [self getPhotoImage:indexPath.row];
    NSDictionary *metadata = [self getPhotoMetaData:indexPath.row];
    NSString *title = [metadata objectForKey:(NSString *)kCGImagePropertyExifUserComment];
    cell.imageView.image = image;
    cell.textLabel.text = [NSString stringWithFormat:@"%@", title];
    return cell;
}
 
#pragma mark Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    [self photoSelect:[self getPhotoImage:indexPath.row]];
}
 
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    return 300;
}
 
#pragma mark PhotoViewControllerDelegate Methods
- (void)photoSelect:(UIImage *)image {
    [delegate photoSelect:image];
}
 
- (void)photoSelectCancel {
    [delegate photoSelectCancel];
}
 
#pragma mark Memory management
- (void)dealloc {
    [super dealloc];
}
    
@end