我正在以编程方式创建UICollectionViewController
。不,我不想像每个教程那样使用IB和Storyboard。我只想使用普通代码。
以下是我viewDidLoad
中的内容:
// UICollectionView
UICollectionViewFlowLayout *aFlowLayout = [[UICollectionViewFlowLayout alloc] init];
[aFlowLayout setItemSize:CGSizeMake(200, 140)];
[aFlowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];
self.collectionView = [[UICollectionView alloc] initWithFrame:self.view.frame collectionViewLayout:aFlowLayout];
[self.collectionView setDelegate:self];
[self.collectionView setDataSource:self];
self.collectionView.backgroundColor = [UIColor clearColor];
[self.collectionView setAutoresizingMask:UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleWidth];
[self.collectionView registerClass:[PUCImageGridCell class] forCellWithReuseIdentifier:CollectionViewCellIdentifier];
我已经实现了所需的委托方法,但仍然会收到此错误:
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'UICollectionView must be initialized with a non-nil layout parameter'
答案 0 :(得分:10)
这是我用来初始化UICollectionViewController:
的方法- (id)initWithCollectionViewLayout:(UICollectionViewLayout *)layout
您无需实例化collectionView,控制器将为您执行此操作。调用后设置框架,或者您可以覆盖并设置内部框架:
- (id)initWithCollectionViewLayout:(UICollectionViewLayout *)layout{
self = [super initWithCollectionViewLayout:layout];
if (self) {
// additional setup here if required.
}
return self;
}
我更喜欢使用autolayout约束。