一、先上gif效果图，DEMO链接：https://gitee.com/xudongxiang/DragDropCollectionView.git
201812251450165.gif
二、代码实现细节
1. 初始化collectionView，以及遵守UICollectionViewDelegate、UICollectionViewDataSource ，并且注册cell等一波常规操作
UICollectionViewFlowLayout *collectionFlowLayout = [[UICollectionViewFlowLayout alloc] init];
collectionFlowLayout.scrollDirection = UICollectionViewScrollDirectionVertical;
self.collectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 0, 375, 667) collectionViewLayout:collectionFlowLayout];
self.collectionView.backgroundColor = [UIColor whiteColor];
[self.collectionView registerClass:[CollectionViewCell class] forCellWithReuseIdentifier:@"cell"];
self.collectionView.dataSource = self;
self.collectionView.delegate = self;
[self.view addSubview:self.collectionView];
2. 为collectionView添加长按手势
// 添加长按抖动手势
[self addRecognize];
- (void)addRecognize
{
UILongPressGestureRecognizer *recognize = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressGestureAction:)];
//设置长按响应时间为0.5秒
recognize.minimumPressDuration = 0.5;
[self.collectionView addGestureRecognizer:recognize];
}
3. 实现长按后collectionView的抖动效果，并且为collectionView添加拖动手势
// 长按抖动手势方法
- (void)longPressGestureAction:(UILongPressGestureRecognizer *)longGesture {
switch (longGesture.state) {
case UIGestureRecognizerStateBegan: {
// 移除长按手势
[self.collectionView removeGestureRecognizer:longGesture];
// 为collectionView添加拖动手势
[self addGesture];
// 用一个BOOL类型的全局变量，记录collectionView是否为抖动状态，YES：抖动，NO：停止抖动
_isItemShake = YES;
[self.collectionView reloadData];
}
break;
case UIGestureRecognizerStateChanged: {}
break;
case UIGestureRecognizerStateEnded: {}
break;
default:
break;
}
}
- (void)addGesture
{
UILongPressGestureRecognizer *longGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handlelongGesture:)];
longGesture.minimumPressDuration = 0;
[self.collectionView addGestureRecognizer:longGesture];
}
4. 实现collectionView的拖动效果，下面会使用iOS9的新特性实现拖拽，必须调用UICollectionView的下面两个方法
// 开始移动的时候调用此方法，可以获取相应的datasource方法设置特殊的indexpath 能否移动,如果能移动返回的是YES ,不能移动返回的是NO
- (BOOL)beginInteractiveMovementForItemAtIndexPath:(NSIndexPath *)indexPath
// 更新移动过程的位置
- (void)updateInteractiveMovementTargetPosition:(CGPoint)targetPosition
// 长按抖动手势方法
- (void)handlelongGesture:(UILongPressGestureRecognizer *)longGesture {
switch (longGesture.state) {
case UIGestureRecognizerStateBegan:{
// 通过手势获取点，通过点获取点击的indexPath， 移动该cell
NSIndexPath *aIndexPath = [self.collectionView indexPathForItemAtPoint:[longGesture locationInView:self.collectionView]];
[self.collectionView beginInteractiveMovementForItemAtIndexPath:aIndexPath];
}
break;
case UIGestureRecognizerStateChanged:{
// 通过手势获取点，通过点获取拖动到的indexPath， 更新该cell位置
[self.collectionView updateInteractiveMovementTargetPosition:[longGesture locationInView:self.collectionView]];
}
break;
case UIGestureRecognizerStateEnded:{
// 移动完成关闭cell移动
[self.collectionView endInteractiveMovement];
// 移除拖动手势
[self.collectionView removeGestureRecognizer:longGesture];
// collectionView停止抖动
_isItemShake = NO;
// 为collectionView添加拖动手势
[self addRecognize];
NSArray *cellArray = [self.collectionView visibleCells];
for (CollectionViewCell *cell in cellArray ) {
// 调用cell停止抖动方法
[cell stopShake];
}
}
break;
default:
[self.collectionView endInteractiveMovement];
[self.collectionView removeGestureRecognizer:longGesture];
_isItemShake = NO;
[self addRecognize];
NSArray *cellArray = [self.collectionView visibleCells];
for (CollectionViewCell *cell in cellArray ) {
[cell stopShake];
}
break;
}
}
5. 实现UICollectionViewDelegate、UICollectionViewDataSource
- (BOOL)collectionView:(UICollectionView *)collectionView canMoveItemAtIndexPath:(NSIndexPath *)indexPath
{
return YES;
}
- (void)collectionView:(UICollectionView *)collectionView moveItemAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath *)destinationIndexPath
{
// 删除数据源中初始位置的数据
id objc = [self.colorArray objectAtIndex:sourceIndexPath.item];
[self.colorArray removeObject:objc];
// 将数据插入数据源中新的位置，实现数据源的更新
[self.colorArray insertObject:objc atIndex:destinationIndexPath.item];
NSArray *cellArray = [self.collectionView visibleCells];
for (CollectionViewCell *cell in cellArray ) {
[cell stopShake];
}
}
//配置cell大小
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
return CGSizeMake(167, 167);
}
//配置行间距
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section
{
return 15;
}
//配置每组上下左右的间距
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
return UIEdgeInsetsMake(0, 13, 15, 13);
}
#pragma mark - UICollectionViewDataSource
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
{
return 1;
}
//配置每个组里面有多少个cell
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
return self.colorArray.count;
}
//配置cell，并且通过_isItemShake控制cell是否抖动
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
CollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"cell" forIndexPath:indexPath];
[cell loadWithModel:self.colorArray[indexPath.row] ];
if (_isItemShake) {
// 调用cell开始抖动方法
[cell beginShake];
}else{
// 调用cell停止抖动方法
[cell stopShake];
}
return cell;
}
6. 在CollectionViewCell.m文件中实现cell的抖动和停止抖动方法
// 实现cell抖动方法
- (void)beginShake
{
CAKeyframeAnimation *anim = [CAKeyframeAnimation animation];
anim.keyPath = @"transform.rotation";
anim.duration = 0.2;
anim.repeatCount = MAXFLOAT;
anim.values = @[@(-0.03),@(0.03),@(-0.03)];
anim.removedOnCompletion = NO;
anim.fillMode = kCAFillModeForwards;
[self.layer addAnimation:anim forKey:@"shake"];
}
// 实现cell停止抖动方法
- (void)stopShake
{
[self.layer removeAllAnimations];
}
