Load-On-Demand self-reference hierarchy provider

Enable the ability to MERGE seperate rows (different records), like found in ITunes "Songs" mode where is shows the artwork (then artist,release undernearth) in a custom class, then the related song rows to the right.

Your competitor Dev Express has it already in place.

See youtube video here :

https://www.youtube.com/watch?v=TfPXwE7GcXs

Cheers

The scenario which should be covered is selecting some data from Excel and pasting in the new row of RadGridView. This is an easy way for inserting data in the grid.

ADD. RadGridView - add support for self-reference hierarchy for child levels as well

Improve RadGridViewDragDropService extensibility to perform visual drop indication over RadTreeView.

Repeat the master template headers right after the end of an expanded detail template. The purpose is clarity for the end user.

The specified format in the DisplayFormat attribute should be considered when automatically generating the GridViewDateTimeColumn.

public RadForm1()
{
    InitializeComponent();

    List<Item> items = new List<Item>();
    for (int i = 0; i < 5; i++)
    {
        items.Add(new Item(DateTime.Now.AddDays(i)));
    }

    this.radGridView1.DataSource = items;
    this.radGridView1.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill;
}

public class Item
{
    [System.ComponentModel.DisplayName("My Date")]
    [System.ComponentModel.DataAnnotations.DisplayFormat(DataFormatString = "{0:MM/dd/yyyy}")]
    public DateTime Date { get; set; }

    public Item(DateTime date)
    {
        this.Date = date;
    }
}

When the pencil icon is clicked the RowValidating event must be fired.

WORKAROUND:
1. When clicking the "pencil" icon, the current row is not changed, thus the RowValidating is not fired. A suitable event to cover this case is the CellValidating event which will be triggered when the "pencil" icon is clicked. 
2. When the pencil is clicked, save the grid's CurrentRow, set it to null and then set it back to the saved row. This will trigger the RowValidating event and the desired logic will be executed. The downside of this approach is that the event will be triggered twice, because we change the CurrentRow twice.


void radGridView1_MouseDown(object sender, MouseEventArgs e)
{
    GridRowHeaderCellElement rowHeader = radGridView1.ElementTree.GetElementAtPoint(e.Location) as GridRowHeaderCellElement;
    if (rowHeader != null)
    {
        GridViewRowInfo saveRow = radGridView1.CurrentRow;
        radGridView1.CurrentRow = null;
        radGridView1.CurrentRow = saveRow;
    }
}

Consider the iTunes Artist mode grid
http://www.telerik.com/forums/itunes-like-grid

How can I enter the Value "" (empty string) in the traditional filter system (not Excel like filter).

The grid does not seem to accept an empty string as an argument to "Equals" through the UI.

Ideally I would like to extend the standard filter menu in traditional filtering (and the filter operator drop down in custom filtering dialog) to contain operators "Is Empty" "Is Not Empty" and "Is Null Or Empty", "Is Not Null And Not Empty"

Regards

Erwin

IMPROVE. RadGridView - In hierarchy the excel-like filtering on child levels to show values only from the rows of the expanded row instead of all rows of the template.

Add a TextAlignment property of GridViewSummaryItem.

Consider the case where there are many child views and you want to export only the ones that actually contain data. 
Currently, you can either export only one view or all. 

One should be able to pass all the views in the ChildViewExporting event.

Workaround:

 private void RadForm1_Load(object sender, EventArgs e)
 {
     this.categoriesTableAdapter.Fill(this.nwindDataSet.Categories);
     this.productsTableAdapter.Fill(this.nwindDataSet.Products);


     radGridView1.AutoGenerateHierarchy = true;
     radGridView1.DataSource = this.nwindDataSet;
     radGridView1.DataMember = "Categories";

     radGridView1.Rows[0].IsExpanded = !radGridView1.Rows[0].IsExpanded;
     radGridView1.Rows[0].IsExpanded = !radGridView1.Rows[0].IsExpanded;
 }
  
 Image expandedSign;
 Image collapsedSign;
 private void radGridView1_ViewCellFormatting(object sender, CellFormattingEventArgs e)
 {
     GridGroupExpanderCellElement expanderCell = e.CellElement as GridGroupExpanderCellElement;
     if (expanderCell != null)
     {
         if (expandedSign == null && expanderCell.Expander.SignImage != null && e.Row.IsExpanded == false)
         {
             expandedSign = expanderCell.Expander.SignImage.Clone() as Image;

         }
         if (collapsedSign == null && expanderCell.Expander.SignImage != null && e.Row.IsExpanded == true)
         {
             collapsedSign = expanderCell.Expander.SignImage.Clone() as Image;

         }
         if (expandedSign != null && collapsedSign != null)
         {
             expanderCell.Expander.SignImage = null;
         }
         if (e.Row.IsExpanded)
         {
             expanderCell.Expander.Image = collapsedSign;
         }
         else
         {
             expanderCell.Expander.Image = expandedSign;
         }

         expanderCell.Expander.ImageLayout = ImageLayout.None;
         expanderCell.Expander.DrawImage = true;
         expanderCell.Expander.ImageAlignment = ContentAlignment.TopLeft;

     }
 }

This new API will be useful for implementing custom sorting scenarios when you need to have custom sorting only for a single column.

A similar API is available for the filtering functionality (MasterTemplate.DataView.FilterEvaluate)

The new mode should allow copying of single cells even when having the SelectionMode set to FullRowSelect. The attached project features a possible workaround.

Currently the mixed hierarchy mode does not work for child templates

IMPROVE. Extend the functionality of formatting the group text when grouping by more than one column is performed on the same group level