iphone - Changing the position of custom UIButton in custom UITableViewCell

Question

I need to change the position of UIButton dynamically. I do this in cellForRowAtIndexPath:. I alter the frame of the button in that method. The change is not displayed when the table is initially displayed. But when I scroll past the cells and come back to it, it gets displayed. Similarly, when I first scroll to cells not visible initially, there is no change. The change occurs when I scroll to it the second time.

I have tried setNeedsDisplay: on both the custom button and the table view. I have done this even in willDisplayCell:forRowAtIndexPath:. How do I solve this?

EDIT: I forgot to mention that I am loading the UITableViewCell from a nib file. Here is the code to resize the frame.

label1.text  = //text from some source
label1.text = [label1.text stringByAppendingString:@"  |"];
[label1 sizeToFit];
CGRect frameAfterResize=label1.frame;
float x=frameAfterResize.origin.x+frameAfterResize.size.width;
button.frame=CGRectMake(x+2, button.frame.origin.y, button.frame.size.width,button.frame.size.height);

Answer 1

Make your own UITableViewCell subclass. Create and add the button to the cell's contentView in your init method, or create and add it lazily via an accessor property. Override layoutSubviews and postion the button as desired.

Something like this:

@implementation MyCustomCell

- (void) init
{
    self = [super initWithStyle: UITableViewCellStyleDefault reuseIdentifier: nil];
    if ( self != nil )  
    {
         _myButton = [[UIButton buttonWithType: UIButtonTypeRoundedRect] retain];
         [self.contentView addSubview: _myButton];
    }

    return self;
}

- (void) layoutSubviews
{
    [super layoutSubviews];

    // dynamic layout logic:
    if ( ... )
    {

         _myButton.frame = CGRectMake( 10, 10, 100, 30 );
    }
    else 
   {
         _myButton.frame = CGRectMake( 20, 10, 50, 30 );

   }
}

Alternatively, you can attempt to do cell layout in - (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath