UICollectionview不工作，我没有得到任何单元

Question

我想使用集合视图和重用集合视图单元格，我必须从服务器得到23图像和名称，我还没有开始因为我是问题面对

这是我的自定义单元格的文件集合视图文件目标C

下面是我的自定义cell.h

#import <UIKit/UIKit.h> 

@interface CustomCell : UICollectionViewCell 

{ 
    UIImageView *imageView; 
} 

@property (nonatomic, retain) UIImageView *imageView; //this imageview is the only thing we need right now. 


@end 

这里是我的自定义cell.m文件

#import "CustomCell.h" 

@implementation CustomCell 

@synthesize imageView; 

- (id)initWithFrame:(CGRect)aRect 
{ 
    if (self = [super initWithFrame:aRect]) 
    { 
    //we create the UIImageView in this overwritten init so that we always have it at hand. 
    imageView = [[UIImageView alloc] init]; 
    //set specs and special wants for the imageView here. 
    [self addSubview:imageView]; //the only place we want to do this addSubview: is here! 

    //You wanted the imageView to react to touches and gestures. We can do that here too. 
    UITapGestureRecognizer * tap=[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(onButtonTapped:)]; 
    [tap setNumberOfTapsRequired:1]; 
    [self addGestureRecognizer:tap]; 


    //We can also prepare views with additional contents here! 
    //just add more labels/views/whatever you want. 
    } 
    return self; 
    } 

    -(void)onButtonTapped:(id)sender 
    { 
    //the response to the gesture. 
    //mind that this is done in the cell. If you don't want things to happen from this cell. 
    //then you can still activate this the way you did in your question. 
    } 
@end 

这些都是在我的普通视图Controller.m或者文件的方法

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath 
{ 
    UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"cvCell" forIndexPath:indexPath]; 

    [[[cell contentView] subviews] makeObjectsPerformSelector:@selector(removeFromSuperview)]; 


    // create a uiview where we can place all views that need to go into this cell 
    UIView * contents=[[UIView alloc]  initWithFrame:cell.contentView.bounds]; 
    [contents setBackgroundColor:[UIColor clearColor]]; 
    [cell.contentView addSubview:contents]; 


    // set tag to the indexPath.row so we can access it later 
    [cell setTag:indexPath.row]; 

    // add interactivity 
    UITapGestureRecognizer * tap=[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(onButtonTapped:)]; 
    [tap setNumberOfTapsRequired:1]; 
    [cell addGestureRecognizer:tap]; 


if (cell.selected) { 
    cell.backgroundColor = [UIColor blueColor]; // highlight selection 
} 
else 
{ 
    cell.backgroundColor = [UIColor redColor]; // Default color 
} 
return cell; 
} 

-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath { 

    UICollectionViewCell *datasetCell =[collectionView cellForItemAtIndexPath:indexPath]; 
    datasetCell.backgroundColor = [UIColor blueColor]; // highlight selection 
} 

-(void)collectionView:(UICollectionView *)collectionView didDeselectItemAtIndexPath:(NSIndexPath *)indexPath { 

UICollectionViewCell *datasetCell =[collectionView cellForItemAtIndexPath:indexPath]; 
datasetCell.backgroundColor = [UIColor redColor]; // Default color 
} 

我没有得到任何细胞，当我提出这个观点，它只是与背景图像空白，我甚至给一张空白的图片，看看如何看，但我没有得到任何东西，请帮助！

Answer 1

单元格不显示，因为您可能没有正确设置数据源和委托。 由于您在故事板中添加了单元格，因此不需要将imageview作为子视图添加到集合视图单元格中。 首先将您在故事板中添加的imageview插口连接到CustomCell。然后取出

{ 
    UIImageView *imageView; 
} 

@property (nonatomic, retain) UIImageView *imageView; 

您可以删除- (id)initWithFrame:(CGRect)aRect这个方法，你可以在awakeFromNib方法

-(void)awakeFromNib { 
    UITapGestureRecognizer * tap=[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(onButtonTapped:)]; 
    [tap setNumberOfTapsRequired:1]; 
    [self addGestureRecognizer:tap]; 
} 

不需要做

imageView = [[UIImageView alloc] init]; 
    [self addSubview:imageView]; 

再在cellForItemAtIndexPath 删除添加点击手势初始化以下几行

[[[cell contentView] subviews] makeObjectsPerformSelector:@selector(removeFromSuperview)]; 
UIView * contents=[[UIView alloc]  initWithFrame:cell.contentView.bounds]; 
[contents setBackgroundColor:[UIColor clearColor]]; 
[cell.contentView addSubview:contents]; 

做出这些更改后，请再试一次