UICollectionView出现空白

Question

我正在尝试使用UICollectionView，但我遇到了很多问题。我有一个UIViewController里面有一个UICollectionView。我已经正确设置了所有代表以及CVcell中的UILabel。视图显示并且在代码中定义为白色。 NSLog发出所有单元格和应该存在的文本，但在实际的UICollectionView中它是空白的，并且除了滚动视图之外没有任何内容。我已经尝试了一切，但似乎无法正常工作。单元格为187 x 187，占据屏幕尺寸的一半，标签位于中间。我将在下面发布代码。

由于

#import "StudentControllerMain.h"
#import "CVcell.h"



@interface StudentControllerMain ()
    @property (nonatomic, strong) IBOutlet UICollectionView *collectionView;
    @property (nonatomic, strong) NSArray *dataArray;


@end

@implementation StudentControllerMain





- (void)viewDidLoad {
    [super viewDidLoad];

    NSMutableArray *firstSection = [[NSMutableArray alloc] init];


    for (int i=0; i<5; i++) {
        [firstSection addObject:[NSString stringWithFormat:@"Cell %d", i]];
    }

    self.dataArray = [[NSArray alloc] initWithObjects:firstSection, nil];




    [self.collectionView registerClass:[CVcell class] forCellWithReuseIdentifier:@"CVcell"];


    // Configure layout

}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    self.collectionView = nil;
    self.dataArray = nil;
    // Dispose of any resources that can be recreated.
}
-(UIStatusBarStyle)preferredStatusBarStyle{
    return UIStatusBarStyleLightContent;
}

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/




-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
    return [self.dataArray count];
}

-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {

    NSMutableArray *sectionArray = [self.dataArray objectAtIndex:section];
    return [sectionArray count];


}

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {

    // Setup cell identifier
    static NSString *cellIdentifier = @"CVcell";
    CVcell *cell = (CVcell *)[collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];
    NSMutableArray *data = [self.dataArray objectAtIndex:indexPath.section];
    NSString *cellData = [data objectAtIndex:indexPath.row];
    NSLog(cellData);
    [cell.title setText:cellData];
    [cell.title setTextColor:[UIColor blackColor]];

    return cell;

}


@end

Answer 1

1. 删除注册类代码;
2. 设置＆＃34;标识符＆＃34;故事板中集合视图单元格的属性（在属性检查器中）;

Answer 2

如果你确定正在调用cellForItemAtIndexPath，那么问题就是所有视图的框架。运行该应用程序并转到该页面。转到调试 - ＆gt;查看调试 - ＆gt;捕获视图层次结构这将显示所有视图及其大小。你看到桌子了吗？它是正确的高度吗？你能看到每个细胞吗？你能看到他们的子视图吗？您可以右键单击每个以打印其尺寸。