ios - 重用 UITableViewCells 来显示喜欢的状态？

Question

我有一个包含大量自定义单元格的 UITableView。每个单元格都有一个实用程序按钮，因此当您从右向左滑动单元格时，您可以选择收藏或删除。

此外，当选择收藏夹时，utilityButton 中的收藏夹按钮将变为红色，否则按钮为白色。

问题是在我滚动 tableView 之后，我选择的单元格最喜欢的按钮(它们曾经是RED)变成了WHITE。我想我在我的细胞重用方法中遗漏了一些重要的东西。

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    ColorCell *cell = [self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    [cell setNeedsUpdateConstraints];
    [cell setRightUtilityButtons:[self rightButtons] WithButtonWidth:58.0f];
    cell.delegate = self;
    return cell;
}

- (NSArray *)rightButtons
{
    NSMutableArray *rightUtilityButtons = [NSMutableArray new];
    [rightUtilityButtons sw_addUtilityButtonWithColor:[UIColor colorWithRed:0.78f green:0.78f blue:0.8f alpha:1.0] icon:[UIImage imageNamed:@"heart"]];
    [rightUtilityButtons sw_addUtilityButtonWithColor:[UIColor colorWithRed:1.0f green:0.231f blue:0.188 alpha:1.0f] icon:[UIImage imageNamed:@"trash"]];
    return rightUtilityButtons;
}

这是单元格的委托(delegate)方法，当触发 utilityButton 时将被调用并显示我如何设置所选按钮的图像，而 heart 是 WHITE 和 heart-选择 是RED。请注意，index == 0 是最喜欢的按钮，后面是删除按钮。

- (void)swipeableTableViewCell:(ColorCell *)cell didTriggerRightUtilityButtonWithIndex:(NSInteger)index
{
    NSIndexPath *cellIndexPath = [self.tableView indexPathForCell:cell];
    ColorModel *model = [self.objects objectAtIndex:cellIndexPath.row / 2];
    if (cellIndexPath.row % 2 == 0) {
        switch (index) {
            case 0:
            {
                if ([self.favouriteArray containsObject:model]) {
                    [self.favouriteArray removeObject:model];
                    [cell.rightUtilityButtons.firstObject setImage:[UIImage imageNamed:@"heart"] forState:UIControlStateNormal];
                }else{
                    [self.favouriteArray addObject:model];
                    [cell.rightUtilityButtons.firstObject setImage:[UIImage imageNamed:@"heart-selected"] forState:UIControlStateNormal];
                }
                [cell hideUtilityButtonsAnimated:YES];
                break;
            }
            case 1:
            {
                [self.objects removeObjectAtIndex:cellIndexPath.row / 2];
                [self.tableView reloadData];
                break;
            }
        }
    }
}

谢谢。

Answer 1

当您滚动表格 View 时，它会重新加载其单元格，并且在 cellForRowAtIndexPath 方法中，您正在重置/分配一组新的实用程序按钮，在这种情况下，心脏按钮是白色的

[cell setRightUtilityButtons:[self rightButtons] WithButtonWidth:58.0f];

您可以像下面这样编写 rightButtons 方法来代替它，它将解决问题。您也不需要监听 didTriggerRightUtilityButtonWithIndex

- (NSArray *)rightButtonsForIndexPath:(NSIndexPath *)indexpath
{
    NSMutableArray *rightUtilityButtons = [NSMutableArray new];
    if (/* row is selected*/) {
        [rightUtilityButtons sw_addUtilityButtonWithColor:[UIColor colorWithRed:0.78f green:0.78f blue:0.8f alpha:1.0] icon:[UIImage imageNamed:@"heart-selected"]];
    } else {
        [rightUtilityButtons sw_addUtilityButtonWithColor:[UIColor colorWithRed:0.78f green:0.78f blue:0.8f alpha:1.0] icon:[UIImage imageNamed:@"heart"]];
    }

    [rightUtilityButtons sw_addUtilityButtonWithColor:[UIColor colorWithRed:1.0f green:0.231f blue:0.188 alpha:1.0f] icon:[UIImage imageNamed:@"trash"]];
    return rightUtilityButtons;
}