Question

我想要一个带有2个按钮的可折叠列表，我尝试使用UITableViewHeaderFooterView，但它没有用。列表内容重叠。以下是我使用的代码。

public class ExpandableTableCell : UITableViewHeaderFooterView
    {
        toggleSection delegates;
        int section;

        public object SelectHederAction { get; }

        public ExpandableTableCell(string title, int section)//, toggleSection del)
        {
            this.TextLabel.Text = title;
            this.section = section;
            //this.delegates = del;
        }
        //UITableViewHeaderFooterView(NSString reuseIdentifier);

        public ExpandableTableCell(NSString reuseIdentifier) : base(reuseIdentifier)
        {
            this.AddGestureRecognizer(UITapGestureRecognizer(this, SelectHederAction));
        }


        public ExpandableTableCell(NSCoder coder) : base(coder)
        { 

        }

        private UIGestureRecognizer UITapGestureRecognizer(ExpandableTableCell expandableTableCell, object selectHederAction)
        {
            delegates(expandableTableCell, expandableTableCell.section);

            return null;
        }

        public override void LayoutSubviews()
        {
            base.LayoutSubviews();
            this.TextLabel.TextColor = UIColor.White;
            this.ContentView.BackgroundColor = UIColor.DarkGray;      

        }

    }




 public partial class ViewController : UIViewController, IUITableViewDataSource, IUITableViewDelegate
    {


        UITableView table;
        List<Sections> sectionList = new List<Sections>();
        public ViewController(IntPtr handle) : base(handle)
        {
            List<string> lstHorror = new List<string>();
            lstHorror.Add("Horror 1");
            lstHorror.Add("Horror 2");
            lstHorror.Add("Horror 3");
            sectionList.Add(new Sections("Horror", lstHorror, false));
            List<string> lstComedy = new List<string>();
            lstHorror.Add("Comedy 1");
            lstHorror.Add("Comedy 2");
            lstHorror.Add("Comedy 3");
            sectionList.Add(new Sections("Comedy", lstComedy, false));
            table = new UITableView(View.Bounds);
            this.View.Add(table);
            table.WeakDataSource = this;//  new MeasurementsDetailsTableSource(sectionList, this.table);
             table.WeakDelegate = this;


        }



        public override void ViewDidLoad()
        {
            base.ViewDidLoad();
            // Perform any additional setup after loading the view, typically from a nib.
        }

        public override void DidReceiveMemoryWarning()
        {
            base.DidReceiveMemoryWarning();
            // Release any cached data, images, etc that aren't in use.
        }

        [Export("tableView:numberOfRowsInSection:")] 
        public nint RowsInSection(UITableView tableView, nint section)
        {
            return sectionList[Int32.Parse(section.ToString())].Movies.Count;
        }
        [Export("tableView:cellForRowAtIndexPath:")]
        public UITableViewCell GetCell(UITableView tableView, NSIndexPath indexPath)
        {
            string CellIdentifier = "celltest";
            UITableViewCell cell = tableView.DequeueReusableCell(CellIdentifier);
            string item = sectionList[Int32.Parse(indexPath.Section.ToString())].Movies[Int32.Parse(indexPath.Row.ToString())];
            if (cell == null)
            {
                cell = new UITableViewCell(UITableViewCellStyle.Subtitle, CellIdentifier);
            }
            cell.FocusStyle = UITableViewCellFocusStyle.Default;

            cell.TextLabel.Text = item;
            return cell;
        }
        [Export("numberOfSectionsInTableView:")]
        public nint NumberOfSections(UITableView tableView)
        { 
            return sectionList.Count;
        }

        //[Export("tableView:heightForHeaderInSection:")]
        //public virtual float GetHeightForHeader(UITableView tableView, int section)
        //{
        //    return 100f;// *section;
        //}
        [Export("tableView:heightForFooterInSection:")]
        public virtual float GetHeightForFooter(UITableView tableView, int section)
        {
            return 2f;
        }

        [Export("tableView:viewForHeaderInSection:")]
        public virtual UIView GetViewForHeader(UITableView tableView, int section)
        {
            var header = new ExpandableTableCell(sectionList[section].Genere, section);//, this.toggleSection);
            return header;
        }




        [Export("tableView:heightForRowAtIndexPath:")]
        public virtual float GetHeightForRow(UITableView tableView, NSIndexPath indexPath)
        {
           if (sectionList[Int32.Parse(indexPath.Section.ToString())].Expandable==true)
            {
                return 44;// * indexPath.Row;

            }
            else
            {
                return 0f;
            }
        }

        //[Export("tableView:titleForHeaderInSection:")]
        //public string TitleForHeader(UITableView tableView, int section)
        //{
        //    return "Header";
        //}

        //public string TitleForFooter(UITableView tableView, int section)
        //{
        //    return "Footer";
        //}

        private void toggleSection(ExpandableTableCell header, int section)
        {
            sectionList[section].Expandable = !sectionList[section].Expandable;
            for (int i = 0; i < sectionList[section].Movies.Count; i++)
            {
                table.BeginUpdates();
                NSIndexPath[] rowsToReload = new NSIndexPath[] {
                     NSIndexPath.FromRowSection(i, section)
                };
                table.ReloadRows(rowsToReload, UITableViewRowAnimation.None);
                table.ReloadData();
                table.EndUpdates();
            }
        }

        //public nint RowsInSection(UITableView tableView, nint section)
        //{
        //    return sectionList[Int32.Parse(section.ToString())].Movies.Count;
        //}
    }

以下是我要找的例子：

只有在点击特定列表项时才会显示编辑和删除按钮。

Answer 1

您可以使用RowSelected和GetHeightForRow代表来实现这一目标。

将代表分配到您的tableview：

this.TableView.Delegate = new MyDelegate();

在RowSelected的子类中实施GetHeightForRow和UITableViewDelegate个委托，如下所示：

public class MyDelegate : UITableViewDelegate
{
    private bool hasCellExpanded = false;
    private int row;

   public override void RowSelected(UITableView tableView, NSIndexPath indexPath)
    {

       row = indexPath.Row;

       if(hasCellExpanded){

           hasCellExpanded = false;

       }else{
            hasCellExpanded = true;
        }

       tableView.BeginUpdates();
       tableView.EndUpdates();

   }


   public override nfloat GetHeightForRow(UITableView tableView, NSIndexPath indexPath)
    {

       if (row == indexPath.Row&&hasCellExpanded){
            return 100;
        }else{

           return 50;
        }

   }
}

它的工作原理如下：

在xamarin ios的可折叠视图

1 个答案: