自定义表格视图单元格按钮在表格视图reloadData之后保持选中状态

Question

When I reload my tableView, my custom cell button does not reload to its initial state. I would like to have the checks return to the "plusImage". Any idea why this isnt working? Does reloadData envoke new reused cells?

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *ReusableIdentifier = @"Cell";
    SetListTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:ReusableIdentifier forIndexPath:indexPath];


    cell.delegate = self;



            UIImage *checkImage = [UIImage imageNamed:@"check.png"];
            UIImage *plusImage  = [UIImage imageNamed:@"plusButton"];



            if ([self.selectedRows containsIndex:indexPath.row]) {
                [cell.plusButton setBackgroundImage:checkImage forState:UIControlStateNormal];
            }
            else {
                [cell.plusButton setBackgroundImage:plusImage forState:UIControlStateNormal];
            }
            cell.tag = indexPath.row;





    return cell;
}

when the cell is prepareForReuse

-(void)prepareForReuse
{
    UIImage *plusImage = [UIImage imageNamed:@"plusImage"];
    [self.plusButton setBackgroundImage:plusImage forState:UIControlStateNormal];
    self.plusButton.enabled = YES;

    [super prepareForReuse];
}

Answer 1

Here's how you should use a UIButton's states:

In interface builder or inside your custom class (in this case: SetListTableViewCell , although I suggest changing that name) you should set the button's background images for different states: UIControlStateNormal & UIControlStateHighlighted . Then set the button's state to Normal or Highlighted instead. So in SetListTableViewCell.m :

- (void)awakeFromNib
{
    [super awakeFromNib];

    [self.plusButton setBackgroundImage:[UIImage imageNamed:@"plusImage"] forState:UIControlStateNormal];
    [self.plusButton setBackgroundImage:[UIImage imageNamed:@"check.png"] forState:UIControlStateHighlighted];

}

-(void)prepareForReuse
{
    [super prepareForReuse];

    self.plusButton.highlighted = NO;
}

and then:

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *ReusableIdentifier = @"Cell";
    SetListTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:ReusableIdentifier forIndexPath:indexPath];

    cell.delegate = self;
    [cell.plusButton setHighlighted: [self.selectedRows containsIndex:indexPath.row]];
    cell.tag = indexPath.row;

    return cell;
}

If you're using TableView's selection, then you can even use:

- (void)setSelected:(BOOL)selected animated:(BOOL)animated
{
    [super setSelected:selected animated:animated];

    // Configure the view for the selected state
    self.plusButton.highlighted = selected;
}