cell展开的几种方式

一.插入新的cell

原理：

（1）定义是否展开，和展开的cell的下标

@property (assign, nonatomic) BOOL isExpand; //是否展开
@property (strong, nonatomic) NSIndexPath *selectedIndexPath;//展开的cell的下标

（2）创建两个不同的cell

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell;
    if (self.isExpand && self.selectedIndexPath.row < indexPath.row && indexPath.row <= self.selectedIndexPath.row + ExpandCount) {   // Expand cell
        cell = [tableView dequeueReusableCellWithIdentifier:@"CsutomExpansionCell" forIndexPath:indexPath];
    } else {    // Normal cell
        cell = [tableView dequeueReusableCellWithIdentifier:@"CustomCell" forIndexPath:indexPath];
    }
    return cell;
}

（3）创建你需要的cell的数量

 if (self.isExpand) {
        return CellCount + ExpandCount;
    }
    return CellCount;

（4）点击的时候向点击的cell下面插入你需要展示的cell（可展开多个），再次点击删除

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    if (!self.selectedIndexPath) {
        self.isExpand = YES;
        self.selectedIndexPath = indexPath;
        [self.tavleView beginUpdates];
        [self.tavleView insertRowsAtIndexPaths:[self indexPathsForExpandRow:indexPath.row] withRowAnimation:UITableViewRowAnimationTop];
        [self.tavleView endUpdates];
    } else {
        if (self.isExpand) {
            if (self.selectedIndexPath == indexPath) {
                self.isExpand = NO;
                [self.tavleView beginUpdates];
                [self.tavleView deleteRowsAtIndexPaths:[self indexPathsForExpandRow:indexPath.row] withRowAnimation:UITableViewRowAnimationTop];
                [self.tavleView endUpdates];
                self.selectedIndexPath = nil;
            } else if (self.selectedIndexPath.row < indexPath.row && indexPath.row <= self.selectedIndexPath.row + ExpandCount) {

            } else {
                self.isExpand = NO;
                [self.tavleView beginUpdates];
                [self.tavleView deleteRowsAtIndexPaths:[self indexPathsForExpandRow:self.selectedIndexPath.row] withRowAnimation:UITableViewRowAnimationTop];
                [self.tavleView endUpdates];
                self.selectedIndexPath = nil;
            }
        }
    }
}

#pragma mark - other

- (NSArray *)indexPathsForExpandRow:(NSInteger)row {
    NSMutableArray *indexPaths = [NSMutableArray array];
    for (int i = 1; i <= ExpandCount; i++) {
        NSIndexPath *idxPth = [NSIndexPath indexPathForRow:row + i inSection:0];
        [indexPaths addObject:idxPth];
    }
    return [indexPaths copy];
}

二.在不同的section里插入cell

原理：

（1）定义是否展开，和展开的cell的下标

（2）创建两个不同的cell

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell;
    if (self.isExpand && self.selectedIndexPath.section == indexPath.section) {     // Expand Cell
        cell = [tableView dequeueReusableCellWithIdentifier:@"CsutomExpansionCell" forIndexPath:indexPath];
    } else {    // Normal Cell
        cell = [tableView dequeueReusableCellWithIdentifier:@"CustomCell" forIndexPath:indexPath];
    }

    return cell;
}

（3）创建你需要展示普通状态下cell，section的数量

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return SectionCount;
}

（4）改变你展开的时候，展开的section的cell的数量

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    if (self.isExpand && self.selectedIndexPath.section == section) {
        return 1 + ExpandCount; //多个数量
    }
    return 1;
}

（5）点击的时候向点击的cell的section内插入你需要展示的cell（可展开多个），再次点击删除

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    if (!self.selectedIndexPath) {
        self.isExpand = YES;
        self.selectedIndexPath = indexPath;
        [self.tableView beginUpdates];
        [self.tableView insertRowsAtIndexPaths:[self indexPathsForExpandSection:indexPath.section] withRowAnimation:UITableViewRowAnimationTop];
        [self.tableView endUpdates];
    } else {
        if (self.isExpand) {
            if (self.selectedIndexPath == indexPath) {
                self.isExpand = NO;
                [self.tableView beginUpdates];
                [self.tableView deleteRowsAtIndexPaths:[self indexPathsForExpandSection:indexPath.section] withRowAnimation:UITableViewRowAnimationTop];
                [self.tableView endUpdates];
                self.selectedIndexPath = nil;
            } else if (self.selectedIndexPath.row != indexPath.row && indexPath.section <= self.selectedIndexPath.section) {
                // Select the expand cell, do the relating dealing.
            } else {
                self.isExpand = NO;
                [self.tableView beginUpdates];
                [self.tableView deleteRowsAtIndexPaths:[self indexPathsForExpandSection:self.selectedIndexPath.section] withRowAnimation:UITableViewRowAnimationTop];
                [self.tableView endUpdates];
                self.selectedIndexPath = nil;
            }
        }
    }
}

- (NSArray *)indexPathsForExpandSection:(NSInteger)section {
    NSMutableArray *indexPaths = [NSMutableArray array];
    for (int i = 1; i <= ExpandCount; i++) {
        NSIndexPath *idxPth = [NSIndexPath indexPathForRow:i inSection:section];
        [indexPaths addObject:idxPth];
    }
    return [indexPaths copy];
}

三.更改cell的高度

原理：

（1）定义是否展开，和展开的cell的下标

（2）创建一个的cell，分上半部分和下半部分

（3）创建cell的高度，分普通情况下的高度和展开后的高度

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    if (self.isExpand && self.selectedIndexPath == indexPath) {
        return 121;
    } else {
        return 44;
    }
}

（4）点击的时候向点击的cell刷新点击的cell

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    if (!self.selectedIndexPath) {
        self.isExpand = YES;
        self.selectedIndexPath = indexPath;
        [self.tableView beginUpdates];
        [self.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
        [self.tableView endUpdates];
    } else {
        if (self.isExpand) {
            if (self.selectedIndexPath == indexPath) {
                self.isExpand = NO;
                [self.tableView beginUpdates];
                [self.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
                [self.tableView endUpdates];
                self.selectedIndexPath = nil;
            } else {
                self.isExpand = NO;
                [self.tableView beginUpdates];
                [self.tableView reloadRowsAtIndexPaths:@[self.selectedIndexPath] withRowAnimation:UITableViewRowAnimationFade];
                [self.tableView endUpdates];
                self.selectedIndexPath = nil;
            }
        }
    }
}

四.自定义section,点击展开相应的cell(下午有空写...)

demo链接

http://pan.baidu.com/s/1c0YQDNE

效果图