Automatically refresh a component in Blazor
I am working on a Blazor page for adding a new object. The object "RepairOrder" has List of object "RepairSection".
On the page there is an area that will loop through the List "RepairOrder"."RepairSections" and show the elements:
<div class="col-lg-10">
@if (sections.Count > 0)
{
foreach (var sec in sections)
{
<h3>Section @sec.SectionNumber</h3>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-5">
<label for="Failure" class="control-label">Failure: </label>
<input for="Failure" class="form-control" bind="@sec.Failure" readonly />
</div>
<div class="col-lg-1"></div>
<div class="col-lg-1">
<label><input type="checkbox" checked="@IsCApprovedChecked(sec)" /> Warranty</label>
</div>
<div class="col-lg-2">
<label><input type="checkbox" value="@IsWarrantyChecked(sec)" /> Repair Approved</label>
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="AdminComments" class="control-label">Admin Comments: </label>
<input for="AdminComments" class="form-control" bind="@sec.AdminComments" readonly />
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="TechComments" class="control-label">Tech Comments: </label>
<input for="TechComments" class="form-control" bind="@sec.TechComments" readonly />
</div>
</div>
}
}
</div>
After all the current sections in the list have been added to the page, there is a button to add a new section. When the button is clicked, the function changes a bool value to true to open a modal as a dialog. The modal contains fields to input a new section elements.
function called to open the modal:
protected void AddSectionCalled()
{
_newSection = new RepairSection();
this.isAddNew = true;
}
Modal Code:
<div class="modal" tabindex="-1" style="display:block" role="dialog">
<div class="modal-dialog modal-dialog-scrollable modal-xl">
<div class="modal-content">
<div class="modal-header">
<h3 class="modal-title">New Repair Section</h3>
<button type="button" class="close" onclick="@CloseModal"><span aria-hidden="true">X</span></button>
</div>
<div class="modal-body">
<form>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-2">
<label for="sectionLetter" class="control-label">Section: </label>
<input for="sectionLetter" class="form-control" bind="@_newSection.SectionNumber" />
</div>
<div class="col-lg-1"></div>
<div class="col-lg-2">
<label><input type="checkbox" bind="@_newSection.Warranty" /> Warranty</label>
</div>
<div class="col-lg-2">
<label><input type="checkbox" bind="@_newSection.CustomerApproved" /> Repair Approved</label>
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="_failure" class="control-label">Failure: </label>
<input for="_failure" class="form-control" bind="@_newSection.Failure"/>
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="_adminComments" class="control-label">Admin Comments: </label>
<input for="_adminComments" class="form-control" bind="@_newSection.AdminComments" />
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="_techComments" class="control-label">Tech Comments: </label>
<input for="_techComments" class="form-control" bind="@_newSection.TechComments"/>
</div>
</div>
<br/>
<button class="btn btn-primary float-left" onclick="AddNewSection">Add New Section</button>
</form>
</div>
</div>
</div>
</div>
When the "Add New Section" button is clicked, the "_newSection" object created from the information collected in the modal is added to the "sections" list that was originally looped through when the page was loaded.
private void AddNewSection()
{
sections.Add(_newSection);
this.StateHasChanged();
this.isAddNew = false;
}
as you can see I added the "StateHasChanged()" after the new section is added to the sections list. However the page does not render to display the new section.
I originally had created dummy data on the page "OnInitAsync()" event that loaded the sections list with data before it was displayed. This way I could make sure the page displayed what was in the list correctly.
How can I make the page re-render the information in the list after user adds a new object to the list?
----Edit-----
Below is the code for the entire page. I will try and minimize this on the weekend, however there really is not a lot here.
@page "/AddRepairOrder"
@using ShopLiveWebVersion2._0.Models
@using ShopLiveWebVersion2._0.DataAccess
@using ShopLiveWebVersion2._0.Services
@using ShopLiveWebVersion2._0.Data
@inject IUriHelper UriHelper
@inject RepairOrderContext context
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10"><h1>Create New Repair Order</h1></div>
</div>
<br /><br />
<form id="AddROForm">
<div class="form-group">
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-2">
<label for="ControlNumber" class="control-label">Repair Order #: </label>
<input for="ControlNumber" class="form-control" bind="@ro.ControlNumber" maxlength="15" required />
</div>
<div class="col-lg-1">
<label for="TagNumber" class="control-label">Tag #: </label>
<input for="TagNumber" class="form-control" bind="@ro.TagNumber" maxlength="8" />
</div>
<div class="col-lg-3">
<label for="VIN" class="control-label">VIN: </label>
<input for="VIN" class="form-control" bind="@ro.VIN" maxlength="18" />
@*<small id="Chasis" class="form-text text-muted">@ro.GetChassisNumber()</small> figure out how to get chassis from vin after box looses focus*@
</div>
<div class="col-lg-2">
<label for="Make" class="control-label">Make: </label>
<input for="Make" class="form-control" bind="@ro.Make" maxlength="30" />
</div>
<div class="col-lg-2">
<label for="Madel" class="control-label">Model: </label>
<input for="Madel" class="form-control" bind="@ro.Madel" maxlength="30" />
</div>
</div>
<div class="row AddRow">
<div class="col-lg-1"></div>
<div class="col-lg-4">
<label for="Customer" class="control-label">Customer: </label>
<input for="Custoemr" class="form-control" bind="@ro.Customer" maxlength="50" />
</div>
<div class="col-lg-2">
<label asp-for="Location" class="control-label">Vehicle Location: </label>
<select asp-for="Location" class="form-control" bind="@ro.Location">
<option value="">-- Select a Location --</option>
@foreach (var loc in Location)
{
<option value="@loc">@loc</option>
}
</select>
</div>
<div class="col-lg-2">
<label asp-for="Assigned" class="control-label">Assigned: </label>
<select asp-for="Assigned" class="form-control" bind="@ro.Assigned">
<option value="">-- Select an Employee --</option>
@foreach (var emp in Employee)
{
<option value="@emp">@emp</option>
}
</select>
</div>
<div class="col-lg-2">
<label asp-for="Status" class="control-label">Status: </label>
<select asp-for="Status" class="form-control" bind="@ro.Status">
<option value="">-- Select a Status --</option>
@foreach (var st in Status)
{
<option value="@st">@st</option>
}
</select>
</div>
</div>
<br />
<div class="row"><div class="col-lg-1"></div><div class="col-lg-10"><hr id="Double" /></div></div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
@if (sections.Count > 0)
{
foreach (var sec in sections)
{
<h3>Section @sec.SectionNumber</h3>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-5">
<label for="Failure" class="control-label">Failure: </label>
<input for="Failure" class="form-control" bind="@sec.Failure" readonly />
</div>
<div class="col-lg-1"></div>
<div class="col-lg-1">
<label><input type="checkbox" checked="@IsCApprovedChecked(sec)" /> Warranty</label>
</div>
<div class="col-lg-2">
<label><input type="checkbox" value="@IsWarrantyChecked(sec)" /> Repair Approved</label>
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="AdminComments" class="control-label">Admin Comments: </label>
<input for="AdminComments" class="form-control" bind="@sec.AdminComments" readonly />
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="TechComments" class="control-label">Tech Comments: </label>
<input for="TechComments" class="form-control" bind="@sec.TechComments" readonly />
</div>
</div>
}
}
</div>
</div>
<div class="row"></div>
</div> @*Form-group*@
</form>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-9">
<br /><br />
<button class="btn btn-primary float-right" onclick="@AddSectionCalled">Add New Section</button>
</div>
</div>
@if (isAddNew == true)
{
<div class="modal" tabindex="-1" style="display:block" role="dialog">
<div class="modal-dialog modal-dialog-scrollable modal-xl">
<div class="modal-content">
<div class="modal-header">
<h3 class="modal-title">New Repair Section</h3>
<button type="button" class="close" onclick="@CloseModal"><span aria-hidden="true">X</span></button>
</div>
<div class="modal-body">
<form>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-2">
<label for="sectionLetter" class="control-label">Section: </label>
<input for="sectionLetter" class="form-control" bind="@_newSection.SectionNumber" />
</div>
<div class="col-lg-1"></div>
<div class="col-lg-2">
<label><input type="checkbox" bind="@_newSection.Warranty" /> Warranty</label>
</div>
<div class="col-lg-2">
<label><input type="checkbox" bind="@_newSection.CustomerApproved" /> Repair Approved</label>
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="_failure" class="control-label">Failure: </label>
<input for="_failure" class="form-control" bind="@_newSection.Failure" />
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="_adminComments" class="control-label">Admin Comments: </label>
<input for="_adminComments" class="form-control" bind="@_newSection.AdminComments" />
</div>
</div>
<div class="row">
<div class="col-lg-1"></div>
<div class="col-lg-10">
<label for="_techComments" class="control-label">Tech Comments: </label>
<input for="_techComments" class="form-control" bind="@_newSection.TechComments" />
</div>
</div>
<br />
<button class="btn btn-primary float-left" onclick="AddNewSection()">Add New Section</button>
</form>
</div>
</div>
</div>
</div>
}
@functions
{
private RepairOrder ro;
private RepairOrder incomingRO;
private RepairOrderDataAccess RoData;
private string chassis;
private List<string> Location;
private List<string> Employee;
private List<string> Status;
private FileService fileService;
private List<RepairSection> sections;
private bool isAddNew;
//for new repair section modal
private RepairSection _newSection;
protected override async Task OnInitAsync()
{
ro = new RepairOrder();
Location = new List<string>();
Employee = new List<string>();
Status = new List<string>();
sections = new List<RepairSection>();
isAddNew = false;
fileService = new FileService();
RoData = new RepairOrderDataAccess(context);
await LoadData();
}
private async Task LoadData()
{
Location = await Task.Run(() => fileService.ReadLocation());
Employee = await Task.Run(() => fileService.ReadEmployees());
Status = await Task.Run(() => fileService.ReadStatus());
}
public string IsCApprovedChecked(RepairSection sc)
{
if (sc.CustomerApproved == true)
{
return "checked";
}
else
{
return "";
}
}
public string IsWarrantyChecked(RepairSection sc)
{
if (sc.Warranty == true)
{
return "checked";
}
else
{
return "";
}
}
protected void AddSectionCalled()
{
_newSection = new RepairSection();
this.isAddNew = true;
}
private void AddNewSection()
{
sections.Add(_newSection);
this.StateHasChanged();
this.isAddNew = false;
}
private void CloseModal()
{
this.isAddNew = false;
}
Answer
There is a problem with the way you have bound the onclick event of the button on the modal form.
you have onclick="AddNewSection()"
- writing it this way will likely be interpreted as a pure javascript call and if you inspect the DOM in your browser tools, you will likely see onclick="AddNewSection()" on the button.
You should have onclick="@AddNewSection"
- this way, Blazor will hook up the onclick event to your C# method.