以上这些就是构成该Demo的重要组成部分了，UICollectionView还有很多的要素在这里面没有讲到，往后我还会再研究这个控件更加高级的的使用，本篇就好比是餐前的开胃小菜吧，希望大家喜欢。附上这个例子的源码：
@implementation ViewController
@synthesize dataSource = _dataSource;
@synthesize longPressGestureRecognizer = _longPressGestureRecognizer;
@synthesize flow = _flow;
@synthesize collect = _collect;
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
//设置背景色
[self.view setBackgroundColor:[UIColor colorWithPatternImage:[UIImage imageNamed:@"back.jpg"]]];
//设置数据源
self.dataSource = [[NSMutableArray alloc] initWithObjects:
@"1.png",@"2.png",@"3.png", @"4.png", @"5.png", @"6.png", @"7.png", @"8.png", @"9.png", @"10.png", @"11.jpg", @"12.JPG",
@"13.JPG", @"14.jpg", @"15.JPG", @"16.png", @"17.png", @"18.png", @"19.png", @"20.png", nil nil];
//初始化布局
self.flow = [[UICollectionViewFlowLayout alloc] init];
self.collect = [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:self.flow];
[self.collect setBackgroundColor:[UIColor clearColor]];
//注册cell 这一步必须要实现
[self.collect registerClass:[CustomCollectionCell class] forCellWithReuseIdentifier:@"CustomCell"];
self.collect.delegate = self;
self.collect.dataSource = self;
[self.collect setFrame:self.view.bounds];
//添加长按手势
self.longPressGestureRecognizer = [[UILongPressGestureRecognizer alloc] init];
[self.longPressGestureRecognizer addTarget:self action:@selector(handleLongPressRecognizer:)];
[self.collect addGestureRecognizer:self.longPressGestureRecognizer];
[self.view addSubview:self.collect];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (void)handleLongPressRecognizer:(UILongPressGestureRecognizer *)gesture{
switch (gesture.state) {
case UIGestureRecognizerStateBegan:{
NSIndexPath *path = [self.collect indexPathForItemAtPoint:[gesture locationInView:gesture.view]];
if(path == nil){
break;
}
[self.collect beginInteractiveMovementForItemAtIndexPath:path];
}
break;
case UIGestureRecognizerStateChanged:
[self.collect updateInteractiveMovementTargetPosition:[gesture locationInView:gesture.view]];
break;
case UIGestureRecognizerStateEnded:
[self.collect endInteractiveMovement];
break;
default:
[self.collect cancelInteractiveMovement];
break;
}
}
#pragma mark UICollectionViewDataSource
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
return self.dataSource.count;
}
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{
return 1;
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
CustomCollectionCell * cell = (CustomCollectionCell *)[collectionView dequeueReusableCellWithReuseIdentifier:@"CustomCell" forIndexPath:indexPath];
UIImage *image = [UIImage imageNamed:[self.dataSource objectAtIndex:indexPath.row]];
[cell setImageWithText:image text:@""];
return cell;
}
- (BOOL)collectionView:(UICollectionView *)collectionView canMoveItemAtIndexPath:(NSIndexPath *)indexPath{
return YES;
}
- (void)collectionView:(UICollectionView *)collectionView moveItemAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath*)destinationIndexPath{
id item = [self.dataSource objectAtIndex:sourceIndexPath.item];
[self.dataSource removeObject:item];
[self.dataSource insertObject:item atIndex:destinationIndexPath.item];
}
#pragma mark UICollectionViewDelegate
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath{
TestViewController *test = [[TestViewController alloc] initWithNibName:@"TestViewController" bundle:nil];
NSString *imageName = [self.dataSource objectAtIndex:indexPath.row];
test.imageName = imageName;
[self.navigationController pushViewController:test animated:YES];
}
- (BOOL)collectionView:(UICollectionView *)collectionView shouldHighlightItemAtIndexPath:(NSIndexPath *)indexPath{
return YES;
}
//选中放大效果
- (void)collectionView:(UICollectionView *)collectionView didHighlightItemAtIndexPath:(NSIndexPath *)indexPath{
// CustomCollectionCell * cell = (CustomCollectionCell *)[collectionView cellForItemAtIndexPath:indexPath];
//
// [UIView animateWithDuration:1 animations:^{
// cell.transform = CGAffineTransformMakeScale(2.0f, 2.0f);
// }];
}
//缩小效果
- (void)collectionView:(UICollectionView *)collectionView didUnhighlightItemAtIndexPath:(NSIndexPath *)indexPath{
// CustomCollectionCell * cell = (CustomCollectionCell *)[collectionView cellForItemAtIndexPath:indexPath];
//
// [UIView animateWithDuration:1 animations:^{
// cell.transform = CGAffineTransformMakeScale(1.0f, 1.0f);
// }];
}
#pragma mark UICollectionViewDelegateFlowLayout
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{
return CGSizeMake(100, 100);
}
/*
* 上左下右间距
*/
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{
return UIEdgeInsetsMake(15, 15, 15, 15);
}
/*
* item space
*/
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section{
return 8;
}
/*
* 行距 20
*/
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section{
return 10;
}
