DxTreeList.StartEditNewRowAsync(Int32, String) Method

Starts editing a new child node of the row with the specified visible index.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.2.dll

NuGet Package: DevExpress.Blazor

Declaration

public Task StartEditNewRowAsync(
    int parentVisibleIndex,
    string fieldName = null
)

Parameters

Name	Type	Description
parentVisibleIndex	Int32	A parent row’s visible index.

Optional Parameters

Name	Type	Default	Description
fieldName	String	null	A field name that defines the column cell where to display an editor. If this parameter is omitted or the EditMode differs from EditCell, the method displays an editor in the first data column whose DataRowEditorVisible equals true.

Returns

Type	Description
Task	A task that is completed when the row is in edit mode.

Remarks

The TreeList’s EditMode property specifies how users edit TreeList data. The StartEditNewRowAsync method behaves as follows depending on the active edit mode:

EditRow (Default)

Displays the edit row for the new child node of the target row and focuses the first editor in the edit row.

EditForm

Displays the inline edit form for the new child node of the target row and focuses the first editor in this form.

PopupEditForm

Invokes the pop-up edit form for the new child node of the target row and focuses the first editor in this form.

EditCell

Displays and focuses an in-place editor in the cell associated with the specified field of the target row’s new child node. The method ignores the fieldName parameter in the following cases:

• No column is bound to the specified field.
• The DataRowEditorVisible property of the column bound to the specified field is disabled.

When the fieldName parameter is omitted or ignored, the method displays an editor in the first data column whose DataRowEditorVisible is true.

Declare a DxTreeListCommandColumn object in the Columns template to display predefined New, Edit, and Delete command buttons in the TreeList component. Alternatively, you can create custom command elements inside or outside the TreeList. Handle a custom element’s click event and call the StartEditNewRowAsync method to start editing the new child node of the target row.

The following code snippet displays icons instead of default command buttons:

Razor

@inject EmployeeTaskService EmployeeTaskService

<DxTreeList @ref="MyTreeList"
            Data="TreeListData"
            KeyFieldName="Id"
            ParentKeyFieldName="ParentId"
            EditMode="TreeListEditMode.EditForm"
            EditModelSaving="TreeList_EditModelSaving"
            DataItemDeleting="TreeList_DataItemDeleting"
            CustomizeEditModel="TreeList_CustomizeEditModel">
    <Columns>
        <DxTreeListCommandColumn Width="90px">
            <HeaderTemplate>
                <a class="oi oi-plus" @onclick="@(() => MyTreeList.StartEditNewRowAsync())" style="text-decoration: none;" href="javascript:void(0);"></a>
            </HeaderTemplate>
            <CellDisplayTemplate>
                <a class="oi oi-pencil" @onclick="@(() => MyTreeList.StartEditRowAsync(context.VisibleIndex))" style="text-decoration: none;" href="javascript:void(0);"></a>
                <a class="oi oi-plus" @onclick="@(() => MyTreeList.StartEditNewRowAsync(context.VisibleIndex))" style="text-decoration: none;" href="javascript:void(0);"></a>
                <a class="oi oi-x" @onclick="@(() => MyTreeList.ShowRowDeleteConfirmation(context.VisibleIndex))" style="text-decoration: none;" href="javascript:void(0);"></a>
            </CellDisplayTemplate>
        </DxTreeListCommandColumn>
        <DxTreeListDataColumn FieldName="Name" Caption="Task" />
        <DxTreeListDataColumn FieldName="EmployeeName" />
        <DxTreeListDataColumn FieldName="StartDate" />
        <DxTreeListDataColumn FieldName="DueDate" />
    </Columns>
    <EditFormTemplate Context="EditFormContext">
        <DxFormLayout CssClass="w-100">
            <DxFormLayoutItem Caption="Task:" ColSpanMd="6">
                @EditFormContext.GetEditor("Name")
            </DxFormLayoutItem>
            <DxFormLayoutItem Caption="Employee Name:" ColSpanMd="6">
                @EditFormContext.GetEditor("EmployeeName")
            </DxFormLayoutItem>
            <DxFormLayoutItem Caption="Start Date:" ColSpanMd="6">
                @EditFormContext.GetEditor("StartDate")
            </DxFormLayoutItem>
            <DxFormLayoutItem Caption="Due Date:" ColSpanMd="6">
                @EditFormContext.GetEditor("DueDate")
            </DxFormLayoutItem>
        </DxFormLayout>
    </EditFormTemplate>
</DxTreeList>

@code {
    ITreeList MyTreeList { get; set; }
    List<EmployeeTask> TreeListData { get; set; }

    protected override void OnInitialized() {
        TreeListData = EmployeeTaskService.GenerateData();
    }
    void TreeList_CustomizeEditModel(TreeListCustomizeEditModelEventArgs e) {
        if (e.IsNew) {
            var newTask = (EmployeeTask)e.EditModel;
            newTask.Id = TreeListData.Max(x => x.Id) + 1;
            if (e.ParentDataItem != null) {
                newTask.ParentId = ((EmployeeTask)e.ParentDataItem).Id;
            }
        }
    }
    async Task TreeList_EditModelSaving(TreeListEditModelSavingEventArgs e) {
        if (e.IsNew)
            TreeListData.Add((EmployeeTask)e.EditModel);
        else
            e.CopyChangesToDataItem();
    }
    async Task TreeList_DataItemDeleting(TreeListDataItemDeletingEventArgs e) {
        TreeListData.Remove((EmployeeTask)e.DataItem);
    }
}

EmployeeTask.cs

public class EmployeeTask{
    public int Id { get; set; }
    public int ParentId { get; set; }
    public string Name { get; set; }
    public string EmployeeName { get; set; }
    public DateTime StartDate { get; set; }
    public DateTime DueDate { get; set; }

    public EmployeeTask(
        int id,
        int parentId,
        string name,
        string employeeName,
        DateTime startDate,
        DateTime dueDate
    )
    {
        Id = id;
        ParentId = parentId;
        Name = name;
        EmployeeName = employeeName;
        StartDate = startDate;
        DueDate = dueDate;
    }
}

EmployeeTaskService.cs

public class EmployeeTaskService {
    public List<EmployeeTask> GenerateData() {
        return new List<EmployeeTask>() {
            new EmployeeTask(1, 0, "Simplify & Clarify Product Messaging", "John Heart", new DateTime(2018, 4, 3), new DateTime(2018, 4, 14)),
            new EmployeeTask(2, 1, "Prepare Financial Reports", "Samantha Bright", new DateTime(2018, 4, 3), new DateTime(2018, 4, 7)),
            new EmployeeTask(3, 1, "Prepare Marketing Plan", "Arthur Miller", new DateTime(2018, 4, 7), new DateTime(2018, 4, 14)),
            new EmployeeTask(4, 0, "Create Action Plan To Improve Customer Engagement", "Robert Reagan", new DateTime(2017, 8, 8), new DateTime(2018, 4, 8)),
            new EmployeeTask(5, 4, "Update Personnel Files", "Greta Sims", new DateTime(2017, 8, 8), new DateTime(2017, 10, 18)),
            new EmployeeTask(6, 4, "Review Health Insurance Options ", "Brett Wade", new DateTime(2017, 9, 27), new DateTime(2017, 11, 10)),
            new EmployeeTask(7, 4, "Choose Between PPO And HMO Health Plan", "Sandra Johnson", new DateTime(2017, 12, 13), new DateTime(2018, 3, 23)),
            new EmployeeTask(8, 4, "Update Google Adwords Strategy", "Ed Holmes", new DateTime(2017, 8, 23), new DateTime(2017, 12, 23)),
            new EmployeeTask(9, 4, "Create New Brochure Design", "Barb Banks", new DateTime(2018, 1, 3), new DateTime(2018, 3, 14)),
            new EmployeeTask(10, 4, "Obtain Price Quote For New Brochure", "Kevin Carter", new DateTime(2018, 2, 1), new DateTime(2018, 3, 15)),
            new EmployeeTask(11, 4, "Brochure Design Review", "Cindy Stanwick", new DateTime(2017, 8, 22), new DateTime(2017, 10, 28)),
            new EmployeeTask(12, 4, "Review Website Re-Design Strategy", "Sammy Hill", new DateTime(2017, 9, 16), new DateTime(2018, 3, 6)),
            new EmployeeTask(13, 4, "Rollout New Website", "Davey Jones", new DateTime(2017, 11, 7), new DateTime(2018, 2, 6)),
            new EmployeeTask(14, 4, "Update Sales/Marketing Strategy", "Victor Norris", new DateTime(2017, 12, 13), new DateTime(2018, 4, 2)),
            new EmployeeTask(15, 4, "Update Sales/Revenue Report", "Mary Stern", new DateTime(2017, 12, 25), new DateTime(2018, 4, 2)),
            new EmployeeTask(16, 4, "Direct Vs Online Sales Comparison Report", "Robin Cosworth", new DateTime(2018, 1, 2), new DateTime(2018, 3, 20)),
            new EmployeeTask(17, 4, "Review Sales Report and Approve Modifications", "Kelly Rodriguez", new DateTime(2017, 9, 4), new DateTime(2017, 10, 30)),
            new EmployeeTask(18, 4, "Update R&D Strategy", "James Anderson", new DateTime(2017, 11, 13), new DateTime(2017, 12, 4)),
            new EmployeeTask(19, 4, "Discuss Updated R&D Strategy", "Antony Remmen", new DateTime(2017, 10, 29), new DateTime(2017, 12, 31)),
            new EmployeeTask(20, 4, "Update QA Strategy", "Olivia Peyton", new DateTime(2017, 10, 31), new DateTime(2017, 11, 2)),
            new EmployeeTask(21, 4, "Schedule Training Events", "Taylor Riley", new DateTime(2017, 11, 19), new DateTime(2018, 4, 7)),
            new EmployeeTask(22, 4, "Approve The Hiring Of John Jeffers", "Amelia Harper", new DateTime(2018, 1, 7), new DateTime(2018, 4, 8)),
            new EmployeeTask(23, 0, "Increase Average Subscription Price ", "Wally Hobbs", new DateTime(2017, 8, 9), new DateTime(2017, 9, 13)),
            new EmployeeTask(24, 23, "Update Non-Compete Agreements", "Brad Jameson", new DateTime(2017, 8, 9), new DateTime(2017, 9, 3)),
            new EmployeeTask(25, 23, "Update Employee Records With New NDA", "Karen Goodson", new DateTime(2017, 8, 23), new DateTime(2018, 9, 10))
        };
    }
}

Program.cs

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

Refer to the following topic for more information: Editing and Validation in Blazor TreeList.

Implements

StartEditNewRowAsync(Int32, String)