为什么 collectionView 单元格没有显示在 iOS 中？

Question

你好，我可以从图库中获取图像，但 collectionViewCells 未显示在 UI.i 上拖放 collectionView 提供了与委托和数据源的连接 methods.but 为什么没有得到 CollectionViewCells.I 有写成这样的代码

- (void)viewDidLoad  
{ 
imagesArray = [NSMutableArray array]; 
[self.collectionView registerNib:[UINib nibWithNibName:@"MyCell" bundle:nil] forCellWithReuseIdentifier:@"CELL"]; 
}   

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info  
{ 
inputImage= info[UIImagePickerControllerEditedImage]; [imagesArray addObject:inputImage];
[picker dismissViewControllerAnimated:YES completion:nil];
} 

-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView; {
return 1;
} 

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section 
{ 
return [imagesArray count];
} 

- (MyCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath 
{ 
MyCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"CELL" forIndexPath:indexPath];
if(!cell) { 
cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"CELL"forIndexPath:indexPath];
}
recipeImageView = (UIImageView *)[cell viewWithTag:100];
recipeImageView.image =[imagesArray objectAtIndex:indexPath.row];        
[collectionView reloadData];
return cell;
}

请有人建议我怎么做this.help 不胜感激

Answer 1

确保您有 imageArray 数据。并尝试在 imagePickerController:didFinishPickingMediaWithInfo: 方法

中重新加载 collectionView

- (void)viewDidLoad { 
 imagesArray = [NSMutableArray array]; 
 [self.collectionView registerNib:[UINib nibWithNibName:@"MyCell" bundle:nil] forCellWithReuseIdentifier:@"CELL"]; 
      }  

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info { 

inputImage= info[UIImagePickerControllerEditedImage];
[imagesArray addObject:inputImage];
[self.collectionView reloadData];
[picker dismissViewControllerAnimated:YES completion:nil];
}

-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView; {
return 1;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section 
{ 
return [imagesArray count];
} 

- (MyCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath 
{ 
MyCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"CELL" forIndexPath:indexPath];
if(!cell) { 
cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"CELL"forIndexPath:indexPath];
}
recipeImageView = (UIImageView *)[cell viewWithTag:100];
recipeImageView.image =[imagesArray objectAtIndex:indexPath.row]; 
return cell;
}

Answer 2

问题是您在 cellForItemAtIndexPath 中调用了 reloadData。这将导致无限循环。

为什么 collectionView 单元格没有显示在 iOS 中？

why collectionViewCells are not displaying in iOS?

ios

uicollectionview