UICollectionView移動

collectionView在iOS9中發佈了一個能夠移動cell的新特性，實現以下：

1.建立collectionView並設置代理

- (UICollectionView *)collectionView{
    if (_collectionView == nil) {
        UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
        layout.itemSize = CGSizeMake(50, 50);
        _collectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 20, self.view.bounds.size.width, self.view.bounds.size.height) collectionViewLayout:layout];
        layout.minimumLineSpacing = 10;
        layout.minimumInteritemSpacing = 10;
        [_collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:@"Cell"];
        _collectionView.backgroundColor = [UIColor cyanColor];
        _collectionView.dataSource = self;
       //此處給其增長長按手勢，用此手勢觸發cell移動效果
        UILongPressGestureRecognizer *longGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handlelongGesture:)];
        [_collectionView addGestureRecognizer:longGesture];
    }
    return _collectionView;
}

2.設置其資源

_dataSource = [NSMutableArray array];
    for (int i = 1; i <= 50; i++) {
        NSString *imageName = [NSString stringWithFormat:@"%d",i];
        [_dataSource addObject:imageName];
    }

3.監聽手勢，並設置其容許移動cell和交換資源

- (void)handlelongGesture:(UILongPressGestureRecognizer *)longGesture {
    //判斷手勢狀態
    switch (longGesture.state) {
        case UIGestureRecognizerStateBegan:{
            //判斷手勢落點位置是否在路徑上
            NSIndexPath *indexPath = [self.collectionView indexPathForItemAtPoint:[longGesture locationInView:self.collectionView]];
            if (indexPath == nil) {
                break;
            }
            //在路徑上則開始移動該路徑上的cell
            [self.collectionView beginInteractiveMovementForItemAtIndexPath:indexPath];
        }
            break;
        case UIGestureRecognizerStateChanged:
            //移動過程中隨時更新cell位置
            [self.collectionView updateInteractiveMovementTargetPosition:[longGesture locationInView:self.collectionView]];
            break;
        case UIGestureRecognizerStateEnded:
            //移動結束後關閉cell移動
            [self.collectionView endInteractiveMovement];
            break;
        default:
            [self.collectionView cancelInteractiveMovement];
            break;
    }
}

- (BOOL)collectionView:(UICollectionView *)collectionView canMoveItemAtIndexPath:(NSIndexPath *)indexPath{
    //返回YES容許其item移動
    return YES;
}

- (void)collectionView:(UICollectionView *)collectionView moveItemAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath*)destinationIndexPath {
    //取出源item數據
    id objc = [_dataSource objectAtIndex:sourceIndexPath.item];
    //從資源數組中移除該數據
    [_dataSource removeObject:objc];
    //將數據插入到資源數組中的目標位置上
    [_dataSource insertObject:objc atIndex:destinationIndexPath.item];
}

原文連接：iOS9 UICollectionView拖拽移動單元格

阿斯頓撒