UICollectionView的使用有两种方法，一种是继承UICollectionViewController，这个Controller会自带一个UICollectionView；另外一种是作为一个视图放在普通的UIViewController里面。
个人更喜欢第二种。下面采用第二种方式简单介绍一下UICollectionView的使用。
实现委托，代码如下
@interface YourViewController : UIViewController<UICollectionViewDataSource,UICollectionViewDelegate>
2.声明UICollectionView，代码如下
@property(nonatomic,retain)UICollectionView*myCollectionView;
3.初始化UICollectionView，代码如下
- (void)viewDidLoad
{
[super viewDidLoad];
[self initConllectionView];
}
-(void)initConllectionView{
CircleLayout*layout=[[CircleLayout alloc] init];
myCollectionView=[[UICollectionView alloc] initWithFrame: collectionViewLayout:layout];
[myCollectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:@"cell"];
=[UIColor whiteColor];
=self;
=self;
[ addSubview:myCollectionView];
[layout release];
}
这里面的CircleLayout继承自UICollectionViewLayout，主要用来表现UICollectionView的布局以及一些属性。
4.实现- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath;
-(UICollectionViewCell*)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
UICollectionViewCell*cell=[collectionView dequeueReusableCellWithReuseIdentifier:CELL_STR forIndexPath:indexPath];
for (UIView*view in ) {
if (view) {
[view removeFromSuperview];
}
}
UIImageView*imgView=[[UIImageView alloc] initWithFrame:CGRectMake(0, 0, ITEM_WIDTH, ITEM_WIDTH)];
if (>4) {
=[UIImage imageNamed:@""];
}else{
=[UIImage imageNamed:@""];
}
[ addSubview:imgView];
[imgView release];
return cell;
}
的大小
-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{
return CGSizeMake(130,130);
}
CircleLayout的代码：
#import <UIKit/>
#import <QuartzCore/>
@interface CircleLayout : UICollectionViewLayout
@property (nonatomic, assign) CGPoint center;
@property (nonatomic, assign) CGFloat radius;
@property (nonatomic, assign) NSInteger cellCount;
@end
#define ITEM_SIZE 130
#import ""
@implementation CircleLayout
@synthesize cellCount,center,radius;
- (void)prepareLayout{
[super prepareLayout];
CGSize size = ;
cellCount=[ numberOfItemsInSection:0];
center=CGPointMake(/2, /2);
radius = MIN(, ) / 2.5;
}
-(CGSize)collectionViewContentSize{
return [self collectionView].;
}
- (UICollectionViewLayoutAttributes *)layoutAttributesForItemAtIndexPath:(NSIndexPath *)path
{
UICollectionViewLayoutAttributes* attributes = [UICollectionViewLayoutAttributes layoutAttributesForCellWithIndexPath:path];
= CGSizeMake(ITEM_SIZE, ITEM_SIZE);
= CGPointMake( + radius * cosf(2 * * M_PI /cellCount),
+ radius * sinf(2 * * M_PI /cellCount));
return attributes;
}
-(NSArray*)layoutAttributesForElementsInRect:(CGRect)rect{
NSMutableArray* attributes = [NSMutableArray array];
for (NSInteger i=0 ; i < ; i++) {
NSIndexPath* indexPath = [NSIndexPath indexPathForItem:i inSection:0];
[attributes addObject:[self layoutAttributesForItemAtIndexPath:indexPath]];
}
return attributes;
}
- (UICollectionViewLayoutAttributes *)initialLayoutAttributesForInsertedItemAtIndexPath:(NSIndexPath *)itemIndexPath{
UICollectionViewLayoutAttributes* attributes = [self layoutAttributesForItemAtIndexPath:itemIndexPath];
= 0.0;
= CGPointMake(, );
return attributes;
}
- (UICollectionViewLayoutAttributes *)finalLayoutAttributesForDeletedItemAtIndexPath:(NSIndexPath *)itemIndexPath
{
UICollectionViewLayoutAttributes* attributes = [self layoutAttributesForItemAtIndexPath:itemIndexPath];
= 0.0;
= CGPointMake(, );
attributes.transform3D = CATransform3DMakeScale(0.1, 0.1, 1.0);
return attributes;
}
@end