1.UITableView协议方法的实现
使用协议方法相对比较简单。
将tableview设置为可编辑状态，然后实现协议方法中交换数据源和交换cell的位置即可。但是这种实现方法不够自定义，就是比较限制。
- 可编辑状态的时候不能点击
- 可编辑状态是右边会有几条杠。（如图）
- 长按移动只有按住右边几条杠才能移动。
_tableView.editing = YES;
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
return YES;
}
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath *)destinationIndexPath
{
//移动cell前交换数据源
[self.dataArray exchangeObjectAtIndex:sourceIndexPath.row withObjectAtIndex:destinationIndexPath.row];
[self.tableView moveRowAtIndexPath:sourceIndexPath toIndexPath:destinationIndexPath];
}
协议方法实现.gif
2.自定义的实现
先上demo地址
使用可以将demo中的UITableView+MoveCell类别引入工程中，然后绑定数据源即可有拖拽效果啦。
__weak typeof(self) weakSelf = self;
[_tableView setDataWithArray:self.dataArray withBlock:^(NSMutableArray *newArray) {
weakSelf.dataArray = newArray;
}];
支持单section的tableview的拖动和多section数据源嵌套型数组的使用，也支持自动上下滑动。先看看效果吧。
单section.gif
多section嵌套数组.gif
实现思路
有点类似我上一篇写的UICollectionView实现长按cell抖动和拖拽移动(支持iOS9以下)
这里我是使用了给tableview添加了一个类别，在类别中实现拖拽效果，这样就能复用了，而且使用起来方便很多。只需要绑定数据源即可
1.首先给tableview添加一个长按手势
//绑定数据源和添加手势
-(void)setDataWithArray:(NSMutableArray *)array withBlock:(moveCellBlock)block{
self.dataArray = [[NSMutableArray alloc] init];
[self.dataArray addObjectsFromArray:array];
self.block = block;
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)];
[self addGestureRecognizer:longPress];
}
2.监测手势的响应方法中的状态响应，根据不同的状态响应不同操作，这里主要分为三个步骤
- 手势开始时，将长按的cell进行截图，获取到的snapView加在tableview上面，然后将cell隐藏起来，这时候我们看到的就是snapView，拖动的也是snapView。
- 手势改变即开始拖动时，这时候做的就是获取移动的位置，然后snapView跟着移动到改位置，这时候snapView可能会移动到上边缘和下边缘的位置，加上判断，如果移动上边缘和下边缘那么就让tableview自动上下滑动，接着更新数据源和交换cell的位置。
- 手势结束即放手时，将snapview移除，原来的cell显示出来即可
-(void)longPress:(UILongPressGestureRecognizer *)longPress
{
switch (longPress.state) {
case UIGestureRecognizerStateBegan:{
[self reloadData];
CGPoint point = [longPress locationOfTouch:0 inView:longPress.view];
self.indexPath = [self indexPathForRowAtPoint:point];
//indexpath可能为空
if (self.indexPath) {
dispatch_async(dispatch_get_main_queue(), ^{
self.moveCell = [self cellForRowAtIndexPath:self.indexPath];
self.snapView = [self.moveCell snapshotViewAfterScreenUpdates:NO];
self.snapView.frame = self.moveCell.frame;
[self addSubview:self.snapView];
self.moveCell.hidden = YES;
[UIView animateWithDuration:0.1 animations:^{
self.snapView.transform = CGAffineTransformScale(self.snapView.transform, 1.03, 1.05);
self.snapView.alpha = 0.8;
}];
});
}
}
break;
case UIGestureRecognizerStateChanged:{
CGPoint point = [longPress locationOfTouch:0 inView:longPress.view];
CGPoint center = self.snapView.center;
center.y = point.y;
self.snapView.center = center;
if ([self checkIfSnapshotMeetsEdge]) {
[self startAutoScrollTimer];
}else{
[self stopAutoScrollTimer];
}
NSIndexPath *exchangeIndex = [self indexPathForRowAtPoint:point];
//exchangeIndex可能为空
if (exchangeIndex) {
[self updateDataWithIndexPath:exchangeIndex];
[self moveRowAtIndexPath:self.indexPath toIndexPath:exchangeIndex];
self.indexPath = exchangeIndex;
}
}
break;
case UIGestureRecognizerStateEnded:{
dispatch_async(dispatch_get_main_queue(), ^{
self.moveCell = [self cellForRowAtIndexPath:self.indexPath];
[UIView animateWithDuration:0.2 animations:^{
self.snapView.center = self.moveCell.center;
self.snapView.transform = CGAffineTransformIdentity;
self.snapView.alpha = 1.0;
} completion:^(BOOL finished) {
self.moveCell.hidden = NO;
[self.snapView removeFromSuperview];
[self stopAutoScrollTimer];
}];
});
}
break;
default:
break;
}
}
更新数据源
-(void)updateDataWithIndexPath:(NSIndexPath *)moveIndexPath
{
//判断是否是嵌套数组
if ([self nestedArrayCheck:self.dataArray]) {
if (self.indexPath.section == moveIndexPath.section) {
NSMutableArray *originalArray = self.dataArray[self.indexPath.section];
[originalArray exchangeObjectAtIndex:self.indexPath.row withObjectAtIndex:moveIndexPath.row];
}else{
NSMutableArray *originalArray = self.dataArray[self.indexPath.section];
NSMutableArray *removeArray = self.dataArray[moveIndexPath.section];
NSString * obj = [originalArray objectAtIndex:self.indexPath.row];
[removeArray insertObject:obj atIndex:moveIndexPath.row];
[originalArray removeObjectAtIndex:self.indexPath.row];
}
}else{
[self.dataArray exchangeObjectAtIndex:self.indexPath.row withObjectAtIndex:moveIndexPath.row];
}
self.block(self.dataArray);
}
检查截图是否到达边缘，并作出响应
- (BOOL)checkIfSnapshotMeetsEdge{
CGFloat minY = CGRectGetMinY(self.snapView.frame);
CGFloat maxY = CGRectGetMaxY(self.snapView.frame);
if (minY < self.contentOffset.y) {
self.autoScrollDirection = SnapshotMeetsEdgeTop;
return YES;
}
if (maxY > self.bounds.size.height + self.contentOffset.y) {
self.autoScrollDirection = SnapshotMeetsEdgeBottom;
return YES;
}
return NO;
}
增加定时器自动滑动
/**
* 创建定时器并运行
*/
- (void)startAutoScrollTimer{
if (self.autoScrollTimer == nil) {
self.autoScrollTimer = [CADisplayLink displayLinkWithTarget:self selector:@selector(startAutoScroll)];
[self.autoScrollTimer addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];
}
}
/**
* 停止定时器并销毁
*/
- (void)stopAutoScrollTimer{
if (self.autoScrollTimer) {
[self.autoScrollTimer invalidate];
self.autoScrollTimer = nil;
}
}
/**
* 开始自动滚动
*/
- (void)startAutoScroll{
CGFloat pixelSpeed = 4;
if (self.autoScrollDirection == SnapshotMeetsEdgeTop) {//向上滚动
if (self.contentOffset.y > 0) {//向下滚动最大范围限制
[self setContentOffset:CGPointMake(0, self.contentOffset.y - pixelSpeed)];
self.snapView.center = CGPointMake(self.snapView.center.x, self.snapView.center.y - pixelSpeed);
}
}else{ //向下滚动
if (self.contentOffset.y + self.bounds.size.height < self.contentSize.height) {//向下滚动最大范围限制
[self setContentOffset:CGPointMake(0, self.contentOffset.y + pixelSpeed)];
self.snapView.center = CGPointMake(self.snapView.center.x, self.snapView.center.y + pixelSpeed);
}
}
/*
交换cell
*/
NSIndexPath *exchangePath= [self indexPathForRowAtPoint:self.snapView.center];
if (exchangePath) {
[self updateDataWithIndexPath:exchangePath];
[self moveRowAtIndexPath:self.indexPath toIndexPath:exchangePath];
self.indexPath = exchangePath;
}
}
