How to set default of filterdescriptor.operator

Hi,

This doesn't seem to work with nullable columns. In my case I have a decimal? field and if when I'm trying to do what you suggested here, the non-null values are filtered out. Any ideas?

Thanks.

I understand what you're saying, I'm already using custom filtering in some of my grids. But what I don't understand is the different behavior of the grid view based on the data type for a column. I don't want to apply a filter, I just want the default filter option to be IsEqualTo. Why does it work for decimal, but not for decimal? ? In my opinion this is an issue of the grid...

Thanks,
Dumi.

I was looking for the same behavior Dumi was above.  I didn't want to apply a filter but rather I just wanted the default operator to be "IsEqualTo".  I simply set the .DataType of the nullable column in question to typeof(int) which didn't affect the data in the row or the native filtering capabilities.  But then the default operator was "IsEqualTo" without having to do anything else. To set the data type of the column do this:

Hi Jared,

Perfect solution! I can get over this issue now ;)

Thanks a lot!

Hi,

I also have problem with filters in columns which types nullable. When i set filter operator like shown below:

grid.Columns[0].FilterDescriptor = new Telerik.WinControls.Data.FilterDescriptor(null, Telerik.WinControls.Data.FilterOperator.IsEqualTo, null);

the filter operator is set properly but the filter icon is shine.

How can I set the filter operator without light on the icon?

All the best

Hello, Zygmunt,

According to the provided picture in your post here, it seems that you are using the ControlDefault theme. In this theme, the filtering icons are represented via RadSvgImages. If I understand you correctly you want to remove the highlight filtering icon although there is a filter applied and display the default icon. To achieve this you can use the ViewCellFormatting event and change the displayed icon:

public RadForm1()
{
    InitializeComponent();

    var filter = new FilterDescriptor(null, FilterOperator.IsEqualTo, null);
    filter.IsFilterEditor = false;
    radGridView1.Columns["column1"].FilterDescriptor = filter;
    radGridView1.ViewCellFormatting += RadGridView1_ViewCellFormatting;
}
private void RadGridView1_ViewCellFormatting(object sender, CellFormattingEventArgs e)
{
    GridFilterCellElement headerCell = e.CellElement as GridFilterCellElement;
    if (headerCell != null && headerCell.ColumnInfo.Name == "column1")
    {
        RadSvgImage svg = RadSvgImage.FromFile(@"..//..//xml.xml");
        headerCell.FilterButton.SvgImage = svg;
    }
}

Here is the XML file with the RadSvgImage for your reference:

<?xml version="1.0" encoding="utf-8"?>
<svg width="19" height="18" viewBox="0, 0, 19, 18" xml="http://www.w3.org/XML/1998/namespace" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xml="http://www.w3.org/XML/1998/namespace" version="1.1">
  <defs>
    <style>
      .cls-1, .cls-2 {
      fill-rule: evenodd;
      }

      .cls-1 {
      fill: url(#linear-gradient);
      }

      .cls-2 {
      fill: url(#linear-gradient-2);
      }
    </style>
    <linearGradient x1="4" y1="9" x2="15" y2="9" gradientUnits="userSpaceOnUse" id="linear-gradient">
      <stop offset="0%" stop-color="#5B83BA" />
      <stop offset="15%" stop-color="#557BB1" />
      <stop offset="41%" stop-color="#436697" />
      <stop offset="74%" stop-color="#28446E" />
      <stop offset="100%" stop-color="#0E2448" />
    </linearGradient>
    <linearGradient x1="6" y1="8.5" x2="13" y2="8.5" gradientUnits="userSpaceOnUse" id="linear-gradient-2">
      <stop offset="0%" stop-color="#F7FCFF" />
      <stop offset="35%" stop-color="#DCEBFB" />
      <stop offset="75%" stop-color="#C4DBF6" />
      <stop offset="100%" stop-color="#BBD5F5" />
    </linearGradient>
  </defs>
  <g id="Layer_3" data-name="Layer 3">
    <polygon points="15,4 4,4 4,6 8,9 8,13 9,14 11,14 11,9 15,6 15,4" fill-rule="evenodd" class="cls-1" style="fill:url(#linear-gradient);" />
    <polygon points="13,5 6,5 6,6 9,8 9,12 10,12 10,8 13,6 13,5" fill-rule="evenodd" class="cls-2" style="fill:url(#linear-gradient-2);" />
  </g>
</svg>

Thus, although there is a FilterDescriptor added for the column1 the filtering icon will not be highlighted:

I hope this helps. If you have other questions please let me know.

Regards,
Nadya
Progress Telerik

I use default theme but when I set filter operator for columns with nullable types using code below:

var filter = new FilterDescriptor(null, FilterOperator.IsEqualTo, null);
filter.IsFilterEditor = false;
gridView.Columns["OcrDataWystawienia"].FilterDescriptor = filter;

the filter icon is like on this picture

but I would like the icon to look like below

Hello, Zygmunt,

According to the provided picture, it seems that you enabled both the Excel-like filtering functionality in RadGridView as well as the basic filtering. Could you please specify which filtering mechanism you intend to use in RadGridView? Mixing them both is not a good approach. 

For your reference, I am providing my sample project where basic filtering is used. You can see that there is a filter applied to the first collection but the icon is not highlighted as shown in my previous reply. You can achieve a similar result when using Excel-like filtering if you prefer to use it. 

Please, keep in mind that when FilterDescriptor is applied to a column, it is desired behavior to highlight the filter button. This way the user can see a clear indication by which columns the grid is filtered.

I hope this helps. Should you have further questions please let me know.

Regards,
Nadya
Progress Telerik

 I would like to use basic filtering. I have in my grid some columns which can take null vaules. Defaultly the filter type for nullable columns are none but  I would like to change it programically to equal at program start.

When I assign the filter descriptor to the column the icon light on but I would like the column look like others on start.

Hi, Zygmunt,

Thank you for clarifying that you want to use the basic filtering functionality. 

Did you give the project sent in my previous reply a try? I have modified the icon in the ViewCellFormatting event to show a non-highlighted icon (the default one) when FilterOperator.IsEqualTo is applied:

var filter = new FilterDescriptor(null, FilterOperator.IsEqualTo, null);
filter.IsFilterEditor = false;
radGridView1.Columns["column1"].FilterDescriptor = filter;

Please let me know how this works for you.

Regards,
Nadya
Progress Telerik

Hi, Zygmunt,

SVG images support was introduced in R2 2020. If you are using an older version you shouldn't be able to access the RadSvgImage class.

In this case, you can use the FilterButton.Image property instead of SvgImage and assign any custom image that is suitable for you in the ViewCellFormatting event:

private void RadGridView1_ViewCellFormatting(object sender, CellFormattingEventArgs e)
{
    GridFilterCellElement headerCell = e.CellElement as GridFilterCellElement;
    if (headerCell != null && headerCell.ColumnInfo.Name == "column1")
    {
        headerCell.FilterButton.Image = myimage;
    }
}

I hope this helps.

Regards,
Nadya
Progress Telerik

Hello, Zygmunt,

If you want to change the default filter operator for a certain column without applying a FilterDescriptor to this column and without indicating any filter is applied, I would recommend you to have a look at the following KB article which is quite useful on this topic:

https://docs.telerik.com/devtools/winforms/knowledge-base/set-default-filter-operators-in-gridview 

Please give it a try and see how it would work for your custom scenario.

Regards,
Dess | Tech Support Engineer, Principal
Progress Telerik