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Cascading values and EventCallback in Blazor with layout component

I have three components that I want to pass values and eventcallbacks through:
First I have MainLayout that is a LayoutComponent
#inherits LayoutComponentBase
<div class="cms-container">
<div class="header">
<div class="header-logo">
CMS
</div>
<div class="header-settings">
<div class="header-settings__alert">
<i class="fa fa-bell"></i>
<div class="header-settings__alert--no">
<div class="header-settings__alert--no__text">
2
</div>
</div>
<ul class="cms-dropdown">
<li class="cms-dropdown__alert">
<span class="cms-dropdown__alert--status"><i class="fa fa-info-circle font-danger"></i></span>
<span class="cms-dropdown__alert--left">Följ upp händelse</span><span class="cms-dropdown__alert--right">1 dgr</span>
</li>
<li class="cms-dropdown__alert">
<span class="cms-dropdown__alert--status"><i class="fa fa-info-circle font-success"></i></span>
<span class="cms-dropdown__alert--left">Tidrapport behöver lämnas in</span><span class="cms-dropdown__alert--right">3 dgr</span>
</li>
</ul>
</div>
<div class="header-settings__org">
<span class="header-settings__org--text">
Kanal10.se
</span>
<ul class="cms-dropdown">
<li class="cms-dropdown__normal">
<div class="cms-dropdown__normal--icon">
<i class="fa fa-tasks"></i>
</div>
<div class="cms-dropdown__normal--text">Uppgifter</div>
</li>
<li class="cms-dropdown__normal">
<div class="cms-dropdown__normal--icon">
<i class="fa fa-users"></i>
</div>
<div class="cms-dropdown__normal--text">Användare</div>
</li>
</ul>
</div>
<div class="header-settings__account">
<i class="fa fa-user"></i>
<ul class="cms-dropdown">
<li class="cms-dropdown__normal">
<div class="cms-dropdown__normal--icon">
<i class="fa fa-user"></i>
</div>
<div class="cms-dropdown__normal--text">Min profil</div>
</li>
<li class="cms-dropdown__normal">
<div class="cms-dropdown__normal--icon">
<i class="fa fa-money-check"></i>
</div>
<div class="cms-dropdown__normal--text">Lönebesked</div>
</li>
</ul>
</div>
<div class="header-settings__system">
<div class="header-settings__system--icon">
<i class="fa fa-cog"></i>
</div>
<ul class="cms-dropdown">
<li class="cms-dropdown__normal">
<div class="cms-dropdown__normal--icon">
<i class="fa fa-bars"></i>
</div>
<div class="cms-dropdown__normal--text">Menyer</div>
</li>
<li class="cms-dropdown__normal">
<div class="cms-dropdown__normal--icon">
<i class="fa fa-users"></i>
</div>
<div class="cms-dropdown__normal--text">Användare</div>
</li>
<li class="cms-dropdown__normal">
<div class="cms-dropdown__normal--icon">
<i class="fa fa-shield-alt"></i>
</div>
<div class="cms-dropdown__normal--text">Behörighetsgrupper</div>
</li>
</ul>
</div>
</div>
</div>
<div class="LeftNav">
<NavMenu />
</div>
<TelerikRootComponent>
<div class="cms-content">
#Body
</div>
</TelerikRootComponent>
<div class="footer">
<div class="footer-body">
<div class="footer-body__left">
</div>
<div class="footer-body__right">
<CascadingValue Value="visible">
<SaveAndCancelBtns OnBtnAction="?" />
</CascadingValue>
</div>
</div>
</div>
</div>
<BlazoredToasts Position="Blazored.Toast.Configuration.ToastPosition.TopCenter"
Timeout="3"
IconType="IconType.FontAwesome"
SuccessClass="success-toast-override"
SuccessIcon="fa fa-thumbs-up" />
#code {
private bool visible = false;
}
Then I have a child component called Buttons.razor
#if (visible == true)
{
<div class="footer-body__right--item">
<button class="btn btn-primary" #onclick="Save" type="submit">Save</button>
</div>
<div class="footer-body__right--item">
<button class="btn btn-cancel" #onclick="Cancel">Cancel</button>
</div>
}
[Parameter] public EventCallback<string> OnBtnAction { get; set; }
[Parameter] public bool visible { get; set; }
private void Save()
{
OnBtnAction.InvokeAsync("Save");
}
private void Cancel()
{
OnBtnAction.InvokeAsync("Cancel");
}
}
And then I have the component razor page called pageDetail.razor
#page "/pages/detail/{Id}"
#page "/pages/detail"
<div class="wrapper">
<div class="cms-content__title">
<div class="cms-content__title-left">
Page Detail
</div>
</div>
<div class="cms-content__page">
<div class="cms-content__page-all">
#if (cmsPage == null)
{
<ErrorMessage Message="Loading..." />
}
else
{
<div class="col-6">
<EditForm Model="cmsPage" OnValidSubmit="SavePage">
<DataAnnotationsValidator />
<ValidationSummary />
<div class="form-group">
<label for="PageTitle">Page Title</label>
<InputText #bind-Value="#cmsPage.PageTitle" class="form-control" id="PageTitle"></InputText>
</div>
<div class="form-group">
<label for="PageTitle">Page Descr</label>
<InputTextArea #bind-Value="#cmsPage.PageDescr" class="form-control" id="PageTitle"></InputTextArea>
</div>
<div class="form-group">
<label for="PageTitle">Page Url</label>
<InputText #bind-Value="#cmsPage.UrlName" class="form-control" id="PageTitle"></InputText>
</div>
<div class="form-group">
<label for="PageTitle">Page Type</label><br />
<TelerikComboBox Data="#cmsPageTypes" TextField="PageType" Width="100%" ValueField="PageTypeId" #bind-Value="selectedValue">
</TelerikComboBox>
<ValidationMessage For="#(() => cmsPage.PageTypeId)" />
</div>
<div class="form-group">
<label for="PageTitle">Parent Page</label><br />
<TelerikTreeView Data="#cmsPages" OnItemClick="#OnItemClickHandler">
<TreeViewBindings>
<TreeViewBinding IdField="PageId" TextField="PageTitle" ParentIdField="ParentId" HasChildrenField="false"></TreeViewBinding>
</TreeViewBindings>
</TelerikTreeView>
</div>
<button class="btn btn-primary" type="submit">Save</button>
<button class="btn btn-danger" #onclick="DeletePage">Delete</button>
<button class="btn btn-info" #onclick="BackToList">Back To List</button>
</EditForm>
</div>
}
</div>
</div>
</div>
#code{
"not sure how to implement the event button action"
}
What I want is to:
On PageDetail set a parameter for visible and if it is true show the buttons in Buttons.razor or hide them
When clicking on a buttton in buttons.razor handle the event on PageDetail.razor for the EditForm there
The thing is how to handle the component that is a LayoutComponent. Not sure how it fits in the logic.
As you can see I have started implementing it but am not sure of how to connect the different parts.
Grateful for help!
Peter

I'd recommend looking at this article: https://chrissainty.com/3-ways-to-communicate-between-components-in-blazor/ but you're part of the way there by using the <CascadingParameter> in your layout.
In your case I'm not keen on using a boolean visible as a cascading parameter, it's a bit simplistic. The cascading value is also in the wrong place for this as it needs to wrap both the #Body render and the buttons.
I'd create a state class and cascade that class to any child that wants to use it, by wrapping the #Body and the <SaveAndCancelBtns ..>
<CascadingValue Value="buttonState" >
<TelerikRootComponent>
<div class="cms-content">
#Body
</div>
</TelerikRootComponent>
<div class="footer">
<div class="footer-body">
<div class="footer-body__left">
</div>
<div class="footer-body__right">
<SaveAndCancelBtns />
</div>
</div>
</div>
</CascadingValue>
You also need to add a value in the layout code:
ButtonStates buttonState = new ButtonStates();
The ButtonStates class should provide the values and events you need, e.g.
public class ButtonStates
{
public bool Visible { get; private set; }
// etc
}
Rather than put all the code here I've created a simple sample repo on github for you:
https://github.com/conficient/CascadingStateExample
Note that I've just used a simple state container and event to pass events from it. EventCallback<T> is specifically used to wire up events between Razor components.

MVC C# Carousel Image

i have been trying to create a carousel image on my MVC application. The below snippet from W3 was just used as an example. The result was the images displayed ont he webpage one below eachother. Do i need to do anything else on the MVC application to resolve this?
<div class="container">
<div id="myCarousel" class="carousel slide" data-ride="carousel">
<!-- Indicators -->
<ol class="carousel-indicators">
<li data-target="#myCarousel" data-slide-to="0" class="active"></li>
<li data-target="#myCarousel" data-slide-to="1"></li>
<li data-target="#myCarousel" data-slide-to="2"></li>
</ol>
<!-- Wrapper for slides -->
<div class="carousel-inner">
<div class="item active">
<img src="https://www.w3schools.com/bootstrap/ny.jpg" alt="Los Angeles" style="width:100%;">
</div>
<div class="item">
<img src="https://www.w3schools.com/bootstrap/chicago.jpg" alt="Chicago" style="width:100%;">
</div>
<div class="item">
<img src="https://www.w3schools.com/bootstrap/newyork.jpg" alt="New york" style="width:100%;">
</div>
</div>
<!-- Left and right controls -->
<a class="left carousel-control" href="#myCarousel" data-slide="prev">
<span class="glyphicon glyphicon-chevron-left"></span>
<span class="sr-only">Previous</span>
</a>
<a class="right carousel-control" href="#myCarousel" data-slide="next">
<span class="glyphicon glyphicon-chevron-right"></span>
<span class="sr-only">Next</span>
</a>
</div>
</div>

I had the same requirement sometime ago and I used below code, look if it works for you.
<div id="carouselExampleControls" class="carousel slide" data-ride="carousel">
<div class="carousel-inner">
#{
var first = true;
}
#foreach (var item in ViewBag.Images)
{
<div class="carousel-item #(first?Html.Raw("active"):Html.Raw(""))">
<img class="d-block w-100" src="#item.Image" alt="#item.Name">
</div>
first = false;
}
</div>
<a class="carousel-control-prev" href="#carouselExampleControls" role="button"
data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleControls" role="button"
data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>

Please Try this.I hope your problem is solved
<div id="demo" class="carousel slide" data-ride="carousel">
<ul class="carousel-indicators">
<li data-target="#demo" data-slide-to="0" class="active"></li>
<li data-target="#demo" data-slide-to="1"></li>
<li data-target="#demo" data-slide-to="2"></li>
</ul>
<div class="carousel-inner" role="listbox">
#{int i = 0;}
#foreach (var item in Model)
{
i++;
var active = i == 1 ? "active" : "";
<div class="carousel-item #active">
<img src="#Url.Content(#item.FilePath)" alt="">
</div>
}
</div>
<a class="carousel-control-prev" href="#demo" data-slide="prev">
<span class="carousel-control-prev-icon"></span>
</a>
<a class="carousel-control-next" href="#demo" data-slide="next">
<span class="carousel-control-next-icon"></span>
</a>
</div>

How to Display Descriptive List Group in .NET core?

I wish to create a UI like this using .NET core MVC framework.
what should my view be like?
i tired looping through each data model and embedding razor code into the same bootstrap tempate but i'm not getting anywhere near the desired functionality.
<div class="container h-100 w-100">
<div class="row w-100 ml-0 mr-0 mt-0 mb-0">
<div class="col-3">
<div class="list-group" id="list-tab" role="tablist">
#{
foreach(var user in Model)
{
<a class="list-group-item list-group-item-action" id="list-#user.FirstName-list" data-toggle="list" href="##user.FirstName" aria-controls="#user.FirstName" role="tab">
#Html.DisplayFor(modelItem => user.FirstName)
</a>
}
}
</div>
</div>
<div class="col-9">
<div class="tab-content" id="nav-tabContent">
#{
foreach(var user in Model)
{
<div class="tab-pane fade show " id="list-#user.FirstName" role="tabpanel" aria-labelledby="list-#user.FirstName-list">
<p>#Html.DisplayFor(modelItem => user.FirstName)</p>
</div>
}
}
</div>
</div>
</div>
</div>
The first part of the list group is getting displayed but when i try clicking on it, i dont get to see the description

First, you are appending "list-" to id of your .tab-pane, while the href for list item does not have that prefix.
Second, you can make the first active selection via JavaScript. Avoid putting fade show in your razor code, or put the condition in loop such that it should add it to only first element.
HTML :
<div class="col-3">
<div class="list-group" id="list-tab" role="tablist">
#foreach (var user in Model)
{
<a class="list-group-item list-group-item-action" id="list-#user.FirstName-list" data-toggle="list" href="##user.FirstName" aria-controls="#user.FirstName" role="tab">
#Html.DisplayFor(modelItem => user.FirstName)
</a>
}
</div>
</div>
<div class="col-9">
<div class="tab-content" id="nav-tabContent">
#foreach (var user in Model)
{
<div class="tab-pane" id="#user.FirstName" role="tabpanel" aria-labelledby="list-#user.FirstName-list">
<p>#Html.DisplayFor(modelItem => user.FirstName)</p>
</div>
}
</div>
</div>
</div>
</div>
JS :
<script>
$(".tab-pane").first().addClass("fade show active");
$(".list-group-item").first().addClass("active");
</script>

Creating an active link on a navigation bar while using a master page

I know there are a lot of questions surrounding this topic online however I cannot get any of the solutions to work for me.I have tried numerous way suggested online. I have a master page with my navigation bar code and I want the active link to be highlighted in green when I am on a particular page of the website. I can't figure out what I am doing wrong or missing to get this to work. I am new to ASP.Net and C# so any help would be appreciated.
Here is my current code in body tags of my master page:
<script>
$(document).ready(function () {
var url = window.location;
$('.sidebar .nav').find('.active').removeClass('active');
$('.sidebar .nav li a').each(function () {
if (this.href == url) {
$(this).parent().addClass('active');
}
});
});
</script>
<form id ="form1" runat="server">
<div class="wrapper">
<div class="sidebar" data-color="green" data-image="../assets/img/side-navship.jpg">
<div class="logo">
<a href="Default.aspx" class="simple-text">
Speed-E
</a>
</div>
<div class="sidebar-wrapper">
<ul class="nav">
<li class="">
<a href="<%= Page.ResolveUrl("~/Default.aspx") %>">
<i class="material-icons">dashboard</i>
<p>Home</p>
</a>
</li>
<li class="">
<a href="<%= Page.ResolveUrl("~/NewCert.aspx") %>">
<i class="material-icons">content_paste</i>
<p>New Certificate</p>
</a>
</li>
</ul>
</div>
</div>
<div class="main-panel">
<nav class="navbar navbar-transparent navbar-absolute">
<div class="container-fluid">
<div class="navbar-header">
<button type="button" class="navbar-toggle" data-toggle="collapse">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#"> </a>
</div>
</div>
</nav>
<div class="content">
<div class="container-fluid">
<asp:ContentPlaceHolder ID="BodyContent"runat="server">
</asp:ContentPlaceHolder>
</div>
</div>
</div>
</div>
</form>

How do you programmatically apply a css class?

I have in an aspx page, some constructions like this:
<div class="weather time-morning active">
<div class="icon">
<i class="sun"></i>
</div>
<div class="content">
<h3>Morning</h3>
<div class="degrees">- 1</div>
<div class="data">
<h2>Sunny</h2>
<div>Wind: E 7 mph</div>
<div>Humidity: 91%</div>
</div>
</div>
</div>
I want in code behind to apply various classes to the tag (and/or add more than one tags, in conjunction to various conditions:
switch (response.currently.summary.ToString())
{
case ("Partly Cloudy"):
//do something
//< i class="cloud windy"></i>
break;
case ("Sunny"):
//do something
//<i class="sun"></i>
//<i class="cloud"></i>
//<i class="sprinkles"></i>
break;
}
I have to say that I started from a static HTML page that mimic the behaviour I want.
Any hints please?
L.E.
For being more precise the whole HTML construction is (statically) like this:
<section>
<div class="weather time-morning active">
<div class="icon">
<i class="sun"></i>
</div>
<div class="content">
<h3>Morning</h3>
<div class="degrees">- 1</div>
<div class="data">
<h2>Sunny</h2>
<div>Wind: E 7 mph</div>
<div>Humidity: 91%</div>
</div>
</div>
</div>
<div class="weather time-day">
<div class="icon">
<i class="sun"></i>
<i class="cloud windy"></i>
</div>
<div class="content">
<h3>Day</h3>
<div class="degrees">+ 3</div>
<div class="data">
<h2>Mostly Sunny</h2>
<div>Wind: N 5 mph</div>
<div>Humidity: 45%</div>
</div>
</div>
</div>
<div class="weather time-evening">
<div class="icon">
<i class="sun"></i>
<i class="cloud"></i>
<i class="sprinkles"></i>
<i class="sprinkles"></i>
<i class="sprinkles"></i>
<i class="sprinkles"></i>
</div>
<div class="content">
<h3>Evening</h3>
<div class="degrees">0</div>
<div class="data">
<h2>Rainy</h2>
<div>Wind: W 12 mph</div>
<div>Humidity: 91%</div>
</div>
</div>
</div>
<div class="weather time-night">
<div class="icon">
<i class="moon"></i>
<i class="cloud"></i>
<div class="snowflakes">
<i class="snowflake"></i>
<i class="snowflake"></i>
<i class="snowflake"></i>
<i class="snowflake"></i>
</div>
</div>
<div class="content">
<h3>Night</h3>
<div class="degrees">- 2</div>
<div class="data">
<h2>Cloudy</h2>
<div>Wind: N 2 mph</div>
<div>Humidity: 47%</div>
</div>
</div>
</div>
</section>
and here conditionally I have to change the tags accordingly to the switch values.

Initially, you have to make your div elements enabled for server side control. In terms of code:
<div id="DivId" runat="server"></div>
Then you could make your checks in your server side code and add the class you want like below:
DivId.CssClass="the name of the css class";

The 'nice' way of doing this would be to change the control you are trying to modify to runat="server" in your aspx
<div id="weatherDiv" runat="server">
And then in your code behind, you can now access the div:
weatherDiv.CssClass = "weather time-morning active";
You can also hack a more MVC Razor paradigm to this with Bind <%#, without the need for a control:
.cs Code Behind
protected string GetWeatherClass(bool extraSprinkles)
{
return extraSprinkles
? "extraSprinkesClass"
: "";
}
.ASPX
<div class="weather <%# GetWeatherClass(true) %>">

based on suggestions, finally I have this approach (don't know if the best, but at least it woks)(MorningTime, MorningDay etc. are ID for corespinding tags):
switch (response.currently.icon.ToString())
{
case ("clear-day"):
//do something
MorningTime.Attributes.Add("class", "sun");
MorningType.Attributes.Add("class", "sun");
DayTime.Attributes.Add("class", "sun");
DayType.Attributes.Add("class", "sun");
break;
case ("partly-cloudy-day"):
//do something
MorningTime.Attributes.Add("class", "sun");
MorningType.Attributes.Add("class", "cloud windy");
DayTime.Attributes.Add("class", "sun");
DayType.Attributes.Add("class", "cloud windy");
EveningTime.Attributes.Add("class", "sun");
EveningType.Attributes.Add("class", "cloud windy");
NightTime.Attributes.Add("class", "moon");
NightType.Attributes.Add("class", "cloud windy");
break;
case ("rain"):
and so on.