Setting custom UITableViewCells height

Your UITableViewDelegate should implement tableView:heightForRowAtIndexPath:

Objective-C

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return [indexPath row] * 20;
}

Swift 5

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    return indexPath.row * 20
}

You will probably want to use NSString's sizeWithFont:constrainedToSize:lineBreakMode: method to calculate your row height rather than just performing some silly math on the indexPath :)

If all your rows are the same height, just set the rowHeight property of the UITableView rather than implementing the heightForRowAtIndexPath. Apple Docs:

There are performance implications to using tableView:heightForRowAtIndexPath: instead of rowHeight. Every time a table view is displayed, it calls tableView:heightForRowAtIndexPath: on the delegate for each of its rows, which can result in a significant performance problem with table views having a large number of rows (approximately 1000 or more).

in a custom UITableViewCell -controller add this

-(void)layoutSubviews {  

    CGRect newCellSubViewsFrame = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
    CGRect newCellViewFrame = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.frame.size.width, self.frame.size.height);

    self.contentView.frame = self.contentView.bounds = self.backgroundView.frame = self.accessoryView.frame = newCellSubViewsFrame;
    self.frame = newCellViewFrame;

    [super layoutSubviews];
}

In the UITableView -controller add this

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return [indexPath row] * 1.5; // your dynamic height...
}

To set automatic dimension for row height & estimated row height, ensure following steps to make, auto dimension effective for cell/row height layout.

• Assign and implement tableview dataSource and delegate
• Assign UITableViewAutomaticDimension to rowHeight & estimatedRowHeight
• Implement delegate/dataSource methods (i.e. heightForRowAt and return a value UITableViewAutomaticDimension to it)

-

Objective C:

// in ViewController.h
#import <UIKit/UIKit.h>

@interface ViewController : UIViewController <UITableViewDelegate, UITableViewDataSource>

  @property IBOutlet UITableView * table;

@end

// in ViewController.m

- (void)viewDidLoad {
    [super viewDidLoad];
    self.table.dataSource = self;
    self.table.delegate = self;

    self.table.rowHeight = UITableViewAutomaticDimension;
    self.table.estimatedRowHeight = UITableViewAutomaticDimension;
}

-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {

    return UITableViewAutomaticDimension;
}

Swift:

@IBOutlet weak var table: UITableView!

override func viewDidLoad() {
    super.viewDidLoad()

    // Don't forget to set dataSource and delegate for table
    table.dataSource = self
    table.delegate = self

    // Set automatic dimensions for row height
    table.rowHeight = UITableViewAutomaticDimension
    table.estimatedRowHeight = UITableViewAutomaticDimension
}



// UITableViewAutomaticDimension calculates height of label contents/text
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    return UITableViewAutomaticDimension
}

For label instance in UITableviewCell

• Set number of lines = 0 (& line break mode = truncate tail)
• Set all constraints (top, bottom, right left) with respect to its superview/ cell container.
• Optional: Set minimum height for label, if you want minimum vertical area covered by label, even if there is no data.

Note: If you've more than one labels (UIElements) with dynamic length, which should be adjusted according to its content size: Adjust 'Content Hugging and Compression Resistance Priority` for labels which you want to expand/compress with higher priority.

Here in this example I set low hugging and high compression resistance priority, that leads to set more priority/importance for contents of second (yellow) label.

Thanks to all the posts on this topic, there are some really helpful ways to adjust the rowHeight of a UITableViewCell.

Here is a compilation of some of the concepts from everyone else that really helps when building for the iPhone and iPad. You can also access different sections and adjust them according to the varying sizes of views.

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    int cellHeight = 0;

    if ([indexPath section] == 0) 
    {
        cellHeight = 16;
        settingsTable.rowHeight = cellHeight;
    }
    else if ([indexPath section] == 1)
    {
        cellHeight = 20;
        settingsTable.rowHeight = cellHeight;
    }

    return cellHeight;
}
else
{
    int cellHeight = 0;

    if ([indexPath section] == 0) 
    {
        cellHeight = 24;
        settingsTable.rowHeight = cellHeight;
    }
    else if ([indexPath section] == 1)
    {
        cellHeight = 40;
        settingsTable.rowHeight = cellHeight;
    }

    return cellHeight;
}
return 0;
}