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Index

DragItem

@page "/"

<h1>Hello, world!</h1>

Welcome to your new app.

<div style="height: 300px;width: 300px;background-color: cornflowerblue;touch-action: none; border: medium;"
     ondragover="event.preventDefault();"
     @ontouchcancel="OnTouch"
     @ontouchend="OnTouch"
     @ontouchenter="OnTouch"
     @ontouchleave="OnTouch"
     @ontouchmove="OnTouch"
     @ontouchstart="OnTouch"
     @ondrag="OnDrag"
     @ondragstart="OnDrag"
     @ondragend="OnDrag"
     @ondragenter="OnDrag"
     @ondragleave="OnDrag"
     @ondrop="OnDrop">
    Drag to Me
</div>

<DragItem></DragItem>
<DragItem></DragItem>
<DragItem></DragItem>
<DragItem></DragItem>

@code{
    private void OnTouch(TouchEventArgs args)
    {
        Console.WriteLine("Index:OnTouch:" + args.Type);
    }

    void OnDrag(DragEventArgs args)
    {
        Console.WriteLine("Index:OnDrag:" + args.Type);
    }

    void OnDrop(DragEventArgs args)
    {
        Console.WriteLine("Index:OnDrop:" + args.Type);
    }
}

namespace BlazorFiddleProject
{
    using Microsoft.AspNetCore.Components.Builder;
    using Microsoft.Extensions.DependencyInjection;


    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
        }

        public void Configure(IComponentsApplicationBuilder app)
        {
            app.AddComponent<App>("app");
        }
    }
}

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8"/>
    <meta name="viewport" content="width=device-width">
    <title>BlazorFiddleProject</title>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
	
	<script src="_content/MatBlazor/dist/matBlazor.js"></script>

    <style>
        app { }
    </style>

    <script type="text/javascript">
    </script>
</head>
<body>
<app>Loading...</app>

<script src="_framework/blazor.webassembly.js"></script>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>

<script>
        function moveItem(guid, dx, dy) {
            var target = document.getElementById(guid);
            var datax = (parseFloat(target.getAttribute('data-x')) || 0)
            var datay = (parseFloat(target.getAttribute('data-y')) || 0)

            // keep the ACCUMULATED dragged position in the data-x/data-y attributes
            var tx = (parseFloat(target.getAttribute('data-x')) || 0) + dx
            var ty = (parseFloat(target.getAttribute('data-y')) || 0) + dy

           
            // translate the element
            target.style.webkitTransform =
                target.style.transform =
                'translate(' + tx + 'px, ' + ty + 'px)'

            // update the posiion attributes
            target.setAttribute('data-x', tx)
            target.setAttribute('data-y', ty)
            //console.log(tx + "," + ty)
        }
    </script>

</body>
</html>

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