GridContextMenuDefaultItemNames.CollapseAll Field

The Collapse All item’s name.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v25.2.dll

NuGet Package: DevExpress.Blazor

Declaration

public const string CollapseAll = "CollapseAll"

Field Value

Type	Description
String	The “CollapseAll” string.

Remarks

Specify the ContextMenus property to display context menus for the following Grid elements:

Collapse All is a Grid context menu item that collapses all group rows. This item is available in group panel and group row context menus if grouping is applied.

Use the CollapseAll field to apply the following customizations:

• Access and customize the Collapse All item
• Add this item to a context menu
• Remove the item from the group panel or group row context menu

Example

The following code snippet adds Expand All/Collapse All items to all context menus:

Razor

@inject WeatherForecastService ForecastService

<DxGrid Data="@Data"
        ShowGroupPanel="true"
        AutoExpandAllGroupRows="true"
        ContextMenus="GridContextMenus.All"
        CustomizeContextMenu="CustomizeContextMenu">
    <Columns>
        <DxGridDataColumn FieldName="Date" DisplayFormat="D" />
        <DxGridDataColumn FieldName="TemperatureC" Caption="@("Temp. (\x2103)")" Width="120px" />
        <DxGridDataColumn FieldName="TemperatureF" Caption="@("Temp. (\x2109)")" Width="120px" />
        <DxGridDataColumn FieldName="Forecast" GroupIndex="0" />
        <DxGridDataColumn FieldName="CloudCover" />
    </Columns>
</DxGrid>

@code {
    object Data { get; set; }

    protected override void OnInitialized() {
        Data = ForecastService.GetForecast();
    }
    void CustomizeContextMenu(GridCustomizeContextMenuEventArgs args) {
        if(!args.Items.Contains(GridContextMenuDefaultItemNames.CollapseAll) && args.Grid.GetGroupCount() > 0)
            args.Items.Add(GridContextMenuDefaultItemNames.CollapseAll);
        if(!args.Items.Contains(GridContextMenuDefaultItemNames.ExpandAll) && args.Grid.GetGroupCount() > 0)
            args.Items.Add(GridContextMenuDefaultItemNames.ExpandAll);
    }
}

WeatherForecast

using System;

public class WeatherForecast {
    public DateTime Date { get; set; }
    public int TemperatureC { get; set; }
    public double TemperatureF => Math.Round((TemperatureC * 1.8 + 32), 2);
    public string Forecast { get; set; }
    public string CloudCover { get; set; }
    public bool Precipitation { get; set; }
}

WeatherForecastService

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

public class WeatherForecastService {
    private List<WeatherForecast> Forecast { get; set; }

    private static string[] CloudCover = new[] {
        "Sunny", "Partly cloudy", "Cloudy", "Storm"
    };

    Tuple<int, string>[] ConditionsForForecast = new Tuple<int, string>[] {
        Tuple.Create( 22 , "Hot"),
        Tuple.Create( 13 , "Warm"),
        Tuple.Create( 0 , "Cold"),
        Tuple.Create( -10 , "Freezing")
    };

    public WeatherForecastService() {
        Forecast = CreateForecast();
    }

    private List<WeatherForecast> CreateForecast() {
        var rng = new Random();
        DateTime startDate = DateTime.Now;
        return Enumerable.Range(1, 15).Select(index => {
            var temperatureC = rng.Next(-10, 30);
            return new WeatherForecast {
                Date = startDate.AddDays(index),               
                TemperatureC = temperatureC,
                CloudCover = CloudCover[rng.Next(0, 4)],
                Precipitation = Convert.ToBoolean(rng.Next(0, 2)),
                Forecast = ConditionsForForecast.First(c => c.Item1 <= temperatureC).Item2
            };
        }).ToList();
    }

    public IEnumerable<WeatherForecast> GetForecast() {
        return Forecast.ToArray();
    }
    // ...
}

Program.cs

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