Blazor Expanding Cards


 

This provides a cool look that can be used for displaying products, pictures, or a wide range of items to your users.

For our sample, we will be using images, set the background image.  It makes a nice demo.


HTML

It turns out this is effect fairly easy to implement.  You have a container and a DIV for each card that you want.

    <div class="container">
        <div class="panel">
            <h3>Explore The World</h3>
        </div>
        <div class="panel">
            <h3>Wild Forest</h3>
        </div>
        <div class="panel">
            <h3>Sunny Beach</h3>
        </div>
        <div class="panel">
            <h3>City on Winter</h3>
        </div>
        <div class="panel">
            <h3>Mountains - Clouds</h3>
        </div>
    </div>


CSS 


The CSS is straightforward as well.  The container is a flexbox.  Each panel within the flexbox is positioned absolutely with a flex of 0.5.

The "trick" comes on with the on-click event.  When a user clicks on one of the panels, we add an "active" class to that panel.  The active class sets the item to flex of 5.


Blazor Stuff

Now for the fun stuff, creating the on-click event and handling it.  We will need to know which panel clicked on so we can add the "active" class to the clicked panel.  But we will need to remove the active class from all the other elements.

We have done several times in the past, usually with a class variable for each panel, then within a foreach we would test to see if the item we are on is the one clicked, if so, we would add the active class, else remove the active class.

This process seems ok, but if we add move panels, we have to create more variables and adjust or for loop.  For this solution, I decided to go a different way.


I have 1 variable called "open".  This holds the panel number that has the active class applied.  On a click, we call a method to set "open".  On each panel HTML class section, we use an if to test if this is the clicked panel.  If so, add the active class, else, don't.  

Added to each panel:

        class="panel @(open == 3 ? "active" : "")" @onclick="@(e=>SetActive(3))"

Now if we add more panels, we just increase the index that the panel is, and everything works.

        class="panel @(open == 4 ? "active" : "")" @onclick="@(e=>SetActive(4))"

Summary

That is it.  A very cool effect with a little work.  You should be able to use this in a wide range of applications.




Comments

Post a Comment

Popular posts from this blog

Yes, Blazor Server can scale!

Image
From the very beginning of the release of Blazor Server naysayers have incorrectly stated that Blazor Server can not scale.  They usually state that the limit is 5,000 concurrent users. There are several misconceptions and wrong assumptions about their statement.  Let's break it down and get a better understanding of Blazor server-side scaling. What is the "limit" for users When Microsoft talks about the need to scale an application, what they are saying is that when a normal response for any concurrent user is taking longer than 200 ms, the system is not performant and needs to scale. We will accept that definition: If any normal user response is taking longer than 200 ms, the system needs to scale for concurrent users. By a normal response, we are referring to a page get, a post, etc.  Large database access requests would not be included in this measurement. What is scaling There are 2 common ways to scale, scale, out horizontally, and scale-up, up vertically. In our di
Read more

Blazor new and improved Search Box

 Back in March, I posted a new Blazor data grid with a search box ( see post ).  Since then I have found a new and improved search box that I wanted to implement.  The search part is implemented the same.  What I added was the ability for the user to narrow down the search by selecting which field they wanted to search on.  This will help the user find what they are looking for and in a large collection, the search will end up being faster. The goal of making the change was to make the search box a new component and have it handle the UI functionality part. Prep Work Here is the prep work I did before adding the search box: Started with the source code from the post listed above. Upgraded the project to .Net 5 Upgraded the Nuget packages that were out of date. Ensured every build and run. Change to a Component I wanted to create a component for the search box so I could use it in other applications.   1. Create a Folder under UIControls called "SearchBox" 2. Created a new raz
Read more

Blazor - Cool Blur Loading Page

Image
  I was working on a project and wanted an original way of showing the user the application was loading besides using the normal "Loading...." text.  I came across a website page and thought I could refactor that into what I was looking for. When my application starts, it displays a full-screen image with a count down while the page loads.  As a special effect, I want to unblur the image the closer it gets to the applicaiton finishing loading.  Once the teh count down is done, we pause for 1 sec, for effect, then proceed to the application.  I think it turned out pretty cool.  See the demo here . I used the server side Blazor project template in my example, but the code should work on any Blazor template. Template changes 1. Rename the original Index.razor page to "home".  Besure to change the routing at the top of the page as well.      @page "/home" 2. Create a new Index.razor page     a. Add routing           @page "/"           @page "/i
Read more