UITableView 滚动移除 UIButton 值

Question

我有一个 UITableview 并添加了 UIButton 作为自定义视图。当我按下按钮时，它会更改所选按钮的标题，但当我滚动它时，它会恢复正常状态。请参阅下面的代码...

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

    static NSString *Cellidentifier = @"DataTableCellId";
    STCustomCell *cell = (STCustomCell *) [tableView dequeueReusableCellWithIdentifier:Cellidentifier];
    if (cell == nil) {

        NSArray *nib = [[NSBundle mainBundle]loadNibNamed:@"CellView" owner:self options:nil];
    cell = nib[0];

        cellButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
        cellButton.tag=indexPath.row;
        [cellButton addTarget:self
                   action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchDown];
        [cellButton setTitle:@"Save" forState:UIControlStateNormal];
        cellButton.frame = CGRectMake(265.0, 20.0, 45.0, 27.0);
        cellButton.layer.borderColor = [UIColor lightGrayColor].CGColor;
        cellButton.tintColor = [UIColor lightGrayColor];
        cellButton.titleLabel.font = [UIFont systemFontOfSize:12.0];
        cellButton.layer.borderWidth = 1.0f;
        cellButton.layer.cornerRadius = 5;
        cellButton.layer.masksToBounds = YES;
        [cell.contentView addSubview:cellButton];

    }

    return cell;
}

-(void)buttonClicked:(UIButton*)sender
{      
        [sender setBackgroundColor:[UIColor lightGrayColor]];
        [sender setTintColor: [UIColor whiteColor]];
        [sender setTitle:@"Saved" forState:UIControlStateNormal];
        [sender addTarget:self
                   action:@selector(saveCell:) forControlEvents:UIControlEventTouchUpInside];
        sender.enabled = NO;
}

Answer 1

首先，检查您的子句是否为 nil，检查您的单元格是否为 nil 并且不要实例化它是没有意义的。并且由于可重用行为，您的按钮会进入初始状态。所以，检查你的按钮的 enabled 属性

   {
    NSMutableDictionary *buttonsState;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    buttonsState = [NSMutableDictionary new];
}


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

    static NSString *Cellidentifier = @"DataTableCellId";
    STCustomCell *cell = (STCustomCell *) [tableView dequeueReusableCellWithIdentifier:Cellidentifier];
    UIButton *cellButton = (UIButton*)[cell.contentView viewWithTag:indexPath.row];
    if (cell == nil) {

        cell = [[STCustomCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:Cellidentifier]
    }
    if (cellButton == nil)
    {
        cellButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
        cellButton.tag=indexPath.row;
        [cell.contentView addSubview:cellButton];

    }

    if ([buttonsState objectForKey:@(indexPath.row)] == nil)
    {
        [cellButton setTitle:@"Save" forState:UIControlStateNormal];
        cellButton.frame = CGRectMake(265.0, 20.0, 45.0, 27.0);
        cellButton.layer.borderColor = [UIColor lightGrayColor].CGColor;
        cellButton.tintColor = [UIColor lightGrayColor];
        cellButton.titleLabel.font = [UIFont systemFontOfSize:12.0];
        cellButton.layer.borderWidth = 1.0f;
        cellButton.layer.cornerRadius = 5;
        cellButton.layer.masksToBounds = YES;
        [cellButton addTarget:self
                       action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchDown];
    }
    else
    {
        [cellButton setBackgroundColor:[UIColor lightGrayColor]];
        [cellButton setTintColor: [UIColor whiteColor]];
        [cellButton setTitle:@"Saved" forState:UIControlStateNormal];
        [cellButton addTarget:self
                       action:@selector(saveCell:) forControlEvents:UIControlEventTouchUpInside];
    }
    return cell;
}

-(void)buttonClicked:(UIButton*)sender
{
    [buttonsState setObject:@YES forKey:@(sender.tag)];

    [sender setBackgroundColor:[UIColor lightGrayColor]];
    [sender setTintColor: [UIColor whiteColor]];
    [sender setTitle:@"Saved" forState:UIControlStateNormal];
    [sender addTarget:self
               action:@selector(saveCell:) forControlEvents:UIControlEventTouchUpInside];
    sender.enabled = NO;
}