滚动tableview时更改计数值

Question

这是我的CellForRowAtIndexPath代码

 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath;
{


static NSString *simpleTableIdentifier = @"PickAClassCell";

cell = (PickAClassCell *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];

if (cell == nil)
{
    NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"PickAClassCell" owner:self options:nil];
    cell = [nib objectAtIndex:0];

}
cell.CountLabel.tag=1000;
[cell.PlusCount addTarget:self action:@selector(PlusButtonSelect :)forControlEvents:UIControlEventTouchUpInside];
 return cell;
}

-(void)PlusButtonSelect :(UIButton *)sender
{
UILabel *label1 = (UILabel *)[sender.superview viewWithTag:1000];
    NSLog(@"%@",label1);


        int count = [label1.text intValue];

        count = count + 1;

    NSString *Strcount= [NSString stringWithFormat:@"%d",count];



    label1.text=Strcount;
}

当我点击加号按钮计数值增加但我的问题是当我滚动tableview时，添加的计数值变为零（默认位置）。

Answer 1

这是因为你写了

int count = [label1.text intValue];

        count = count + 1; 

每次滚动下一个单元格时，都会使用按钮的初始值初始化计数，而不是使用上一个单元格的按钮int值。

Answer 2

if ($window.scrollTop() > navShiftBreakpoint) { $navContainer.addClass( 'full' );} //full = the second nav & //navShiftBreakpoint = 500px

每次表格视图单元格出现在屏幕上时，此委托调用。尝试在任何变量的帮助下设置计数标签的标记，或尝试通过pickAClassCell添加它。

在你的情况下 (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 每次滚动表格视图单元格时都会执行此行。

Answer 3

试试这个 -

-(void)viewDidLoad {

    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    //userCountHolder is instance of NSMutableArray.
    userCountHolder  = [NSMutableArray arrayWithObjects:@"0",@"0",@"0", nil];
}

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{


    static NSString *simpleTableIdentifier = @"PickAClassCell";

    cell = (PickAClassCell *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];

    if (cell == nil)
    {
        NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"PickAClassCell" owner:self options:nil];
        cell = [nib objectAtIndex:0];

    }
    cell.CountLabel.text = [userCountHolder objectAtIndex:indexPath.row];
    [cell.PlusCount addTarget:self action:@selector(PlusButtonSelect :)forControlEvents:UIControlEventTouchUpInside];
    return cell;
}

-(void)PlusButtonSelect :(UIButton *)sender{

    CGPoint buttonPosition = [sender convertPoint:CGPointZero toView:self.tableView];
    NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:buttonPosition];

    int count = [[userCountHolder objectAtIndex:indexPath.row] intValue];
    count++;
    [userCountHolder replaceObjectAtIndex:indexPath.row withObject:[NSNumber numberWithInt:count]];
    [self.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationNone];
}

Answer 4

在cellForRowAtIndexPath

中试试

if ([self.selectedRows containsObject:indexPath])
{
    // set count values here 
    cell.countLabel.text = @"";
    cell.textLabel.textColor = [UIColor grayColor];
    cell.selectionStyle = UITableViewCellSelectionStyleNone;
}
else
{
    //set the normal cells values
}

此处self.selectedRows是一个数组，当用户点击加号或减号按钮时，您必须存储cellIndexPath值。