自定义UITableViewCell子类无法获取分配的属性

Question

我正在尝试通过ALAssets库构建我的图像选择器，我有一个带有相册的表格视图，但是当我点击相册查看照片时，在由自定义UITableViewCells组成的动态UITableViewController中它不允许我分配属性到我的自定义AlbumContentTableViewCells ......

cell.rowNumber＆amp; indexPath.row是NSIntegers但它抱怨一个无法识别的选择器......

// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

AlbumContentsTableViewCell *cell = [[AlbumContentsTableViewCell alloc] init];

cell = (AlbumContentsTableViewCell*)[tableView dequeueReusableCellWithIdentifier:@"Photo"];

cell.rowNumber = indexPath.row;
cell.selectionDelegate = self;

// Configure the cell...
NSUInteger firstPhotoInCell = indexPath.row * 4;
NSUInteger lastPhotoInCell  = firstPhotoInCell + 4;

if (assets.count <= firstPhotoInCell) {
    NSLog(@"We are out of range, asking to start with photo %d but we only have %d", firstPhotoInCell, assets.count);
    return nil;
}

NSUInteger currentPhotoIndex = 0;
NSUInteger lastPhotoIndex = MIN(lastPhotoInCell, assets.count);
for ( ; firstPhotoInCell + currentPhotoIndex < lastPhotoIndex ; currentPhotoIndex++) {

    ALAsset *asset = [assets objectAtIndex:firstPhotoInCell + currentPhotoIndex];
    CGImageRef thumbnailImageRef = [asset thumbnail];
    UIImage *thumbnail = [UIImage imageWithCGImage:thumbnailImageRef];

    switch (currentPhotoIndex) {
        case 0:
            [cell photo1].image = thumbnail;
            break;
        case 1:
            [cell photo2].image = thumbnail;
            break;
        case 2:
            [cell photo3].image = thumbnail;
            break;
        case 3:
            [cell photo4].image = thumbnail;
            break;
        default:
            break;
    }
}

return cell;

}

当我尝试为此自定义UITableCell分配其'rowNumber'属性时出现此错误：

  

'NSInvalidArgumentException'，原因：' - [UITableViewCell   setRowNumber：]：无法识别的选择器发送到实例0x1e2a43a0'

AlbumContentsTableViewCell.h

#import <UIKit/UIKit.h>

#import "ThumbnailImageView.h"

@class AlbumContentsTableViewCell;

@protocol AlbumContentsTableViewCellSelectionDelegate <NSObject>
- (void)albumContentsTableViewCell:(AlbumContentsTableViewCell *)cell selectedPhotoAtIndex:(NSUInteger)index;
@end

@interface AlbumContentsTableViewCell : UITableViewCell <ThumbnailImageViewSelectionDelegate> {

IBOutlet ThumbnailImageView *photo1;
IBOutlet ThumbnailImageView *photo2;
IBOutlet ThumbnailImageView *photo3;
IBOutlet ThumbnailImageView *photo4;

NSInteger rowNumber;
//id <AlbumContentsTableViewCellSelectionDelegate> selectionDelegate;
}

@property (nonatomic) NSInteger rowNumber;
@property (nonatomic, weak) id<AlbumContentsTableViewCellSelectionDelegate> selectionDelegate;

- (UIImageView *)photo1;
- (UIImageView *)photo2;
- (UIImageView *)photo3;
- (UIImageView *)photo4;

- (void)clearSelection;
@end

AlbumContentsTableViewCell.m

#import "AlbumContentsTableViewCell.h"
#import "ThumbnailImageView.h"

@implementation AlbumContentsTableViewCell

@synthesize rowNumber;
@synthesize selectionDelegate;

 #import <UIKit/UIKit.h>

@class ThumbnailImageView;

@protocol ThumbnailImageViewSelectionDelegate <NSObject>
- (void)thumbnailImageViewWasSelected:(ThumbnailImageView *)thumbnailImageView;
@end

@interface ThumbnailImageView : UIImageView {

UIImageView *highlightView;
id <ThumbnailImageViewSelectionDelegate> delegate;
}

@property(nonatomic, assign) id<ThumbnailImageViewSelectionDelegate> delegate;

- (void)clearSelection;
@end

Answer 1

看起来像是在打电话

[tableView dequeueReusableCellWithIdentifier:@"Photo"];

它正在出现一个UITableViewCell，而不是一个AlbumContentsTableViewCell。由于UITableViewCell没有setRowNumber：选择器，因此它会引发异常。你需要在某处分配和启动你的AlbumContentsTableViewCells。

修改
您需要注册AlbumContentsTableViewCell以与@“Photo”标识符一起使用。尝试将此添加到`viewDidLoad'方法：

    [self.tableView registerClass:[AlbumContentsTableViewCell class] forCellReuseIdentifier:@"Photo"];

请注意，我还没有测试过这段代码，但我认为它接近你所需要的。