How to resize the row height of a UITableView automatically in xamarin ios

问题

I am new in xamarin.ios I want to resize the row height according to the content length. How can I do that.

Here is my ViewController.Cs

 public override void ViewWillAppear(bool animated)
    {
        base.ViewWillAppear(animated);

        nfloat _width = UIScreen.MainScreen.Bounds.Width / 3;
        DataBinding();

        _table = new UITableView(new CGRect(0, 0, View.Frame.Width, View.Frame.Height));
        _table.Source = new DetailsTableViewSource(_caseDesign);
        _table.RowHeight = UITableView.AutomaticDimension;
        _table.EstimatedRowHeight = 100f;         
        _table.ReloadData();
        View.AddSubview(_table);
    }

DetailsTableViewSource.Cs

   public class DetailsTableViewSource : UITableViewSource
{
    public List<CaseDetails> tabledata;

    public DetailsTableViewSource(List<CaseDetails> items)
    {
        tabledata = items;
    }

    public override UITableViewCell GetCell(UITableView tableView, NSIndexPath indexPath)
    {
        NSString cellIdentifier = new NSString();
        var cell = tableView.DequeueReusableCell(cellIdentifier) as CaseDetailsTableCell;
        if (cell == null)
            cell = new CaseDetailsTableCell(cellIdentifier);

        cell.UpdateCell(tabledata[indexPath.Row].Title
                , tabledata[indexPath.Row].Description                  
                );
        return cell;
    }

    public override nint RowsInSection(UITableView tableview, nint section)
    {
        return tabledata.Count;
    }
}

CaseDetailsTableCell.cs

  public class CaseDetailsTableCell:UITableViewCell
{
    UILabel _qst1, _answer1, _seperator;
    nfloat _width;

    public CaseDetailsTableCell(NSString cellId) : base(UITableViewCellStyle.Default, cellId)
        {
         _width = UIScreen.MainScreen.Bounds.Width / 3;

        _qst1 = new UILabel();

        _qst1.Font = _qst1.Font.WithSize(15);

         _seperator = new UILabel();          
        _seperator.TextAlignment = UITextAlignment.Center;
        _seperator.Text = ":";
        _seperator.Font = _seperator.Font.WithSize(20);

        _answer1 = new UILabel();

        _answer1.Font = _answer1.Font.WithSize(15);

        ContentView.AddSubviews(new UIView[] { _qst1, _seperator, _answer1 });
    }

    public void UpdateCell(string Quetion, string Answer)
    {
        _qst1.Text = Quetion;
        _answer1.Text = Answer;
    }

    public override void LayoutSubviews()
    {
        base.LayoutSubviews();
        _qst1.Frame = new CGRect(10, 10, _width + 10, 30);
        _qst1.Lines = 0;
        _qst1.SizeToFit();
        _qst1.LineBreakMode = UILineBreakMode.Clip;
        _qst1.TextAlignment = UITextAlignment.Left;

        _answer1.Frame = new CGRect(_width * 2, 10, UIScreen.MainScreen.Bounds.Width / 3 - 10, 30);
        _answer1.SizeToFit();
        _answer1.TextAlignment = UITextAlignment.Justified;
        _answer1.LineBreakMode = UILineBreakMode.WordWrap;
        _seperator.Frame = new CGRect(_width + 10, 10, UIScreen.MainScreen.Bounds.Width / 3, 30);
       // _date.Frame = new CGRect(17, 50, 50, 20);
    }
}

I want to bind some data into the table and the length of the each item is different, according to the length of the data, the row height is automatically resize . How can i do that.

Now the table look like this

I want the table like this

回答1:

If you want to automatically resize the tableView's row height, you should use autoLayout to place your controls in the cell instead of the Frame. Also put the constraints code in the constructor of the cell will be better:

public CaseDetailsTableCell(NSString cellId) : base(UITableViewCellStyle.Default, cellId)
{
    _width = UIScreen.MainScreen.Bounds.Width / 3;

    _qst1 = new UILabel();

    _qst1.Font = _qst1.Font.WithSize(15);

    _seperator = new UILabel();
    _seperator.TextAlignment = UITextAlignment.Center;
    _seperator.Text = ":";
    _seperator.Font = _seperator.Font.WithSize(20);

    _answer1 = new UILabel();

    _answer1.Font = _answer1.Font.WithSize(15);

    ContentView.AddSubviews(new UIView[] { _qst1, _seperator, _answer1 });

    // Disable this to enable autoLayout
    _qst1.TranslatesAutoresizingMaskIntoConstraints = false;

    var qstLeading = NSLayoutConstraint.Create(_qst1, NSLayoutAttribute.Leading, NSLayoutRelation.Equal, ContentView, NSLayoutAttribute.Leading, 1, 10);
    var qstTop = NSLayoutConstraint.Create(_qst1, NSLayoutAttribute.Top, NSLayoutRelation.Equal, ContentView, NSLayoutAttribute.Top, 1, 10);
    var qstWidth = NSLayoutConstraint.Create(_qst1, NSLayoutAttribute.Width, NSLayoutRelation.Equal, null, NSLayoutAttribute.NoAttribute, 0, _width + 10);
    var qstBottom = NSLayoutConstraint.Create(_qst1, NSLayoutAttribute.Bottom, NSLayoutRelation.LessThanOrEqual, ContentView, NSLayoutAttribute.Bottom, 1, -10);
    _qst1.Lines = 0;
    _qst1.SizeToFit();
    _qst1.LineBreakMode = UILineBreakMode.Clip;
    _qst1.TextAlignment = UITextAlignment.Left;
    _qst1.BackgroundColor = UIColor.Blue;

    _seperator.TranslatesAutoresizingMaskIntoConstraints = false;

    var sepLeading = NSLayoutConstraint.Create(_seperator, NSLayoutAttribute.Leading, NSLayoutRelation.Equal, _qst1, NSLayoutAttribute.Trailing, 1, 10);
    var sepTop = NSLayoutConstraint.Create(_seperator, NSLayoutAttribute.Top, NSLayoutRelation.Equal, ContentView, NSLayoutAttribute.Top, 1, 10);
    var sepWidth = NSLayoutConstraint.Create(_seperator, NSLayoutAttribute.Width, NSLayoutRelation.Equal, null, NSLayoutAttribute.NoAttribute, 0, UIScreen.MainScreen.Bounds.Width / 3);
    _seperator.BackgroundColor = UIColor.Yellow;

    _answer1.TranslatesAutoresizingMaskIntoConstraints = false;

    var ansLeading = NSLayoutConstraint.Create(_answer1, NSLayoutAttribute.Leading, NSLayoutRelation.Equal, _seperator, NSLayoutAttribute.Trailing, 1, 10);
    var ansTop = NSLayoutConstraint.Create(_answer1, NSLayoutAttribute.Top, NSLayoutRelation.Equal, ContentView, NSLayoutAttribute.Top, 1, 10);
    var ansTrailing = NSLayoutConstraint.Create(_answer1, NSLayoutAttribute.Trailing, NSLayoutRelation.Equal, ContentView, NSLayoutAttribute.Trailing, 1, -10);
    var ansBottom = NSLayoutConstraint.Create(_answer1, NSLayoutAttribute.Bottom, NSLayoutRelation.LessThanOrEqual, ContentView, NSLayoutAttribute.Bottom, 1, -10);

    _answer1.SizeToFit();
    _answer1.TextAlignment = UITextAlignment.Justified;
    _answer1.LineBreakMode = UILineBreakMode.WordWrap;
    _answer1.BackgroundColor = UIColor.Red;
    _answer1.Lines = 0;

    ContentView.AddConstraints(new NSLayoutConstraint[] { qstTop, qstLeading, qstWidth, qstBottom, sepLeading, sepTop, sepWidth, ansLeading, ansTop, ansTrailing, ansBottom });
}

Here I add the LessThanOrEqual NSLayoutRelation to bottom constraint of the _qst1 and _answer1 labels, the cell will adjust its height depending on the tallest one. You can adjust the constraints to fit your requirements.

来源：https://stackoverflow.com/questions/50830434/how-to-resize-the-row-height-of-a-uitableview-automatically-in-xamarin-ios