GridGroupRowCommandContext.GroupColumn Property

Returns the grouping column.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v25.2.dll

Declaration

public IGridDataColumn GroupColumn { get; }

Property Value

Type	Description
IGridDataColumn	A Grid data column.

Remarks

The DevExpress Blazor Grid allows you to display context menus with predefined and custom commands. Use the ContextMenus property to activate context menus for specific Grid elements. Handle the CustomizeContextMenu event to modify the menu item collection. Use the Context event argument to identify the target Grid element and obtain contextual information.

When the target element is a group row, the Context property returns a GridGroupRowCommandContext object. Use the object’s GroupColumn property to access the grouping column.

Example

The following example adds custom Promote Group Level/Demote Group Level commands to the group row context menu:

Razor

@inject WeatherForecastService ForecastService

<DxGrid Data="@forecasts"
        ShowGroupPanel="true"
        ContextMenus="GridContextMenus.GroupRow"
        CustomizeContextMenu="OnCustomizeContextMenu">
    <Columns>
        <DxGridSelectionColumn />
        <DxGridDataColumn FieldName=@nameof(WeatherForecast.TemperatureC) Caption="Temp. (C)" GroupIndex="1" />
        <DxGridDataColumn FieldName=@nameof(WeatherForecast.TemperatureF) Caption="Temp. (F)" />
        <DxGridDataColumn FieldName=@nameof(WeatherForecast.Summary) Caption="Summary" GroupIndex="0" />
        <DxGridDataColumn FieldName=@nameof(WeatherForecast.Date) DisplayFormat="dd/MM/yyyy" />
    </Columns>
    <GroupSummary>
        <DxGridSummaryItem SummaryType="GridSummaryItemType.Count" FieldName="Date" FooterColumnName="Date" />
    </GroupSummary>
</DxGrid>

@code {
    private List<WeatherForecast>? forecasts;

    protected override async Task OnInitializedAsync() {
        forecasts = await ForecastService.GetForecastAsync();
    }
    void OnCustomizeContextMenu(GridCustomizeContextMenuEventArgs args) {
        if (args.Context is GridGroupRowCommandContext groupRowContext) {
            args.Items.AddCustomItem(0, "Promote Group Level", () => {
                groupRowContext.Grid.BeginUpdate();
                if (groupRowContext.Grid.GetRowLevel(groupRowContext.RowVisibleIndex) !=0)
                    groupRowContext.GroupColumn.GroupIndex--;
                groupRowContext.Grid.EndUpdate();
            });
            args.Items.AddCustomItem(0, "Demote Group Level", () => {
                groupRowContext.Grid.BeginUpdate();
                var maxGroupLevel = groupRowContext.Grid.GetGroupCount();
                if (groupRowContext.Grid.GetRowLevel(groupRowContext.RowVisibleIndex) != maxGroupLevel)
                    groupRowContext.GroupColumn.GroupIndex++;
                groupRowContext.Grid.EndUpdate();
            });
        }
    }
}

WeatherForecast

using System;

public class WeatherForecast {
    public int ID { get; set; }
    public DateTime Date { get; set; }
    public int TemperatureC { get; set; }
    public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
    public string? Summary { get; set; }
}

WeatherForecastService

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

public class WeatherForecastService {
    public readonly string[] Summaries = new[] {
        "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
    };
    private List<WeatherForecast>? Forecasts;
    public Task<List<WeatherForecast>> GetForecastAsync() {
        if (Forecasts == null) {
            var rnd = new Random();
            Forecasts = Enumerable.Range(1, 50).Select(index => new WeatherForecast {
                ID = index,
                Date = DateTime.Today.AddDays(index),
                TemperatureC = rnd.Next(-20, 55),
                Summary = Summaries[rnd.Next(Summaries.Length)]
            }).ToList();
        }
        return Task.FromResult(Forecasts);
    }
    public Task<List<WeatherForecast>> ChangeForecastAsync(WeatherForecast changed) {
        var originalForecast = Forecasts.FirstOrDefault(i => i.ID == changed.ID);
        if (originalForecast != null) {
            originalForecast.TemperatureC = changed.TemperatureC;
            originalForecast.Summary = changed.Summary;
            originalForecast.Date = changed.Date;
        } else {
            Forecasts.Add(changed);
        }
        return Task.FromResult(Forecasts);
    }
    public Task<List<WeatherForecast>> Remove(WeatherForecast forecast) {
        Forecasts.Remove(forecast);
        return Task.FromResult(Forecasts);
    }
}

Program.cs

// ...
builder.Services.AddSingleton<WeatherForecastService>();