Backend API
<template>
<div v-if="connectionStarted">
<DxDataGrid
id="gridContainer"
:data-source="dataSource"
:repaint-changes-only="true"
:highlight-changes="true"
:show-borders="true"
>
<DxColumn
:width="115"
data-field="lastUpdate"
data-type="date"
format="longTime"
/>
<DxColumn
data-field="symbol"
/>
<DxColumn
data-field="price"
data-type="number"
format="#0.####"
cell-template="priceCellTemplate"
/>
<DxColumn
:width="140"
data-field="change"
data-type="number"
format="#0.####"
cell-template="changeCellTemplate"
/>
<DxColumn
data-field="dayOpen"
data-type="number"
format="#0.####"
/>
<DxColumn
data-field="dayMin"
data-type="number"
format="#0.####"
/>
<DxColumn
data-field="dayMax"
data-type="number"
format="#0.####"
/>
<template #priceCellTemplate="{ data: cellData }">
<PriceCell :cell-data="cellData"/>
</template>
<template #changeCellTemplate="{ data: cellData }">
<ChangeCell :cell-data="cellData"/>
</template>
</DxDataGrid>
</div>
</template>
<script setup lang="ts">
import { onMounted, ref } from 'vue';
import {
DxDataGrid,
DxColumn,
} from 'devextreme-vue/data-grid';
import { CustomStore } from 'devextreme-vue/common/data';
import { HubConnectionBuilder, HttpTransportType } from '@aspnet/signalr';
import PriceCell from './PriceCell.vue';
import ChangeCell from './ChangeCell.vue';
const connectionStarted = ref(false);
const dataSource = ref<CustomStore | undefined>(undefined);
onMounted(() => {
const hubConnection = new HubConnectionBuilder()
.withUrl('https://js.devexpress.com/Demos/NetCore/liveUpdateSignalRHub', {
skipNegotiation: true,
transport: HttpTransportType.WebSockets,
})
.build();
const store = new CustomStore({
load: () => hubConnection.invoke('getAllStocks'),
key: 'symbol',
});
hubConnection
.start()
.then(() => {
hubConnection.on('updateStockPrice', (data) => {
store.push([{ type: 'update', key: data.symbol, data }]);
});
dataSource.value = store;
connectionStarted.value = true;
});
});
</script>
<style>
#gridContainer span.current-value {
display: inline-block;
margin-right: 5px;
}
#gridContainer span.diff {
width: 50px;
display: inline-block;
}
#gridContainer .inc {
color: var(--dx-color-success);
}
#gridContainer .dec {
color: var(--dx-color-danger);
}
#gridContainer .inc .arrow,
#gridContainer .dec .arrow {
display: inline-block;
height: 10px;
width: 10px;
background-repeat: no-repeat;
background-size: 10px 10px;
}
#gridContainer .inc .arrow {
background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABQAAAAUCAYAAACNiR0NAAAABGdBTUEAAK/INwWK6QAAABl0RVh0U29mdHdhcmUAQWRvYmUgSW1hZ2VSZWFkeXHJZTwAAADKSURBVHjaYtTaLs1ABEiG0nPRJa56PEHhsxBhmCUQT4OyrwHxcXyKmQgYJgHE64CYDYrXQcXIMhCbAcgWkGzgNKh38QUB0QamIUUErkhKI9ZAGyCeTERkTYaqxWsgKA2txhdG6GGsvUNGGpeBRMUiGhCFGsqGzUBQQJsxkA5AemaiG5hDIBIIgQSgK0FmMDACs549kN5FZLjhA7+A2A2U9YSAOBeLAk4gnoBDczoOcSFGPIUDPxB/wCHHiKtwYGKgMhg1cBAaCBBgAJTUIL3ToPZfAAAAAElFTkSuQmCC');
}
#gridContainer .dec .arrow {
background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABQAAAAUCAYAAACNiR0NAAAABGdBTUEAAK/INwWK6QAAABl0RVh0U29mdHdhcmUAQWRvYmUgSW1hZ2VSZWFkeXHJZTwAAADJSURBVHjaYvzPgBfgkhYA4o8QFahKmBioDEYNHIQGsgBxIBCLkqgvAYi/g1mMjMjir0EJzR6If/6HpChKMMgMe3DKBeIcKhiY8x/MYoDj+RQYNgdkGLqBbEB8kgzDToL1YjEQhKWB+BUJhj0H64Eahs1AELYhMpJ+gtUiGYbLQBBOI8LANLBaIg1kAAc0vkiAqSPBQFAkHcNi2DGoHMkGgrAENOCRI0ECRQ2JBoKwJTQCfkLZDPgMZPxPXN5NhtJzMSsJVBMAAgwAyWSY2svfmrwAAAAASUVORK5CYII=');
}
</style>
<template>
<div :class="{ inc: cellData.data.change > 0, dec: cellData.data.change < 0 }">
<span class="current-value">{{ cellData.text }}</span>
<span class="arrow"/>
<span class="diff">{{ cellData.data.percentChange.toFixed(2) }}%</span>
</div>
</template>
<script setup lang="ts">
import { type DxDataGridTypes } from 'devextreme-vue/data-grid';
defineProps<{
cellData: DxDataGridTypes.ColumnCellTemplateData
}>();
</script>
<template>
<div :class="{ inc: cellData.data.change > 0, dec: cellData.data.change < 0 }">
<span>{{ cellData.text }}</span>
</div>
</template>
<script setup lang="ts">
import { type DxDataGridTypes } from 'devextreme-vue/data-grid';
defineProps<{
cellData: DxDataGridTypes.ColumnCellTemplateData
}>();
</script>
import { createApp } from 'vue';
import App from './App.vue';
createApp(App).mount('#app');
<!DOCTYPE html>
<html lang="en">
<head>
<title>DevExtreme Demo</title>
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0" />
<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/26.1.5/css/dx.light.css" />
<link rel="stylesheet" type="text/css" href="./bundle.css" />
</head>
<body class="dx-viewport">
<div class="demo-container">
<div id="app"> </div>
</div>
<script src="bundles/vendor/vue.vendor.js"></script>
<script src="./bundle.js"></script>
</body>
</html>
using System.Collections.Generic;
using DevExtreme.MVC.Demos.Models.SignalR;
using Microsoft.AspNet.SignalR;
namespace DevExtreme.MVC.Demos.Hubs {
public class LiveUpdateSignalRHub : Hub {
private readonly StockTicker _stockTicker;
public LiveUpdateSignalRHub() {
_stockTicker = StockTicker.Instance;
}
public IEnumerable<Stock> GetAllStocks() {
return _stockTicker.GetAllStocks();
}
}
}
using System;
using System.Collections.Generic;
using System.Threading;
using DevExtreme.MVC.Demos.Hubs;
using Microsoft.AspNet.SignalR;
using Microsoft.AspNet.SignalR.Hubs;
using DevExpress.Data.Utils;
namespace DevExtreme.MVC.Demos.Models.SignalR {
public class StockTicker {
public readonly static StockTicker Instance = new StockTicker(GlobalHost.ConnectionManager.GetHubContext<LiveUpdateSignalRHub>().Clients);
private readonly IEnumerable<Stock> _stocks;
private IHubConnectionContext<dynamic> Clients { get; set; }
private readonly TimeSpan _updateInterval = TimeSpan.FromMilliseconds(500);
private readonly NonCryptographicRandom _updateOrNotRandom = NonCryptographicRandom.System;
private readonly Timer _timer;
private readonly object _updateStockPricesLock = new object();
static readonly NonCryptographicRandom random = NonCryptographicRandom.System;
private StockTicker(IHubConnectionContext<dynamic> clients) {
Clients = clients;
_stocks = GenerateStocks();
_timer = new Timer(UpdateStockPrices, null, _updateInterval, _updateInterval);
}
public IEnumerable<Stock> GetAllStocks() {
return _stocks;
}
static IEnumerable<Stock> GenerateStocks() {
return new[] {
new Stock(37.95M) { Symbol = "MSFT", DayOpen=36.5M, LastUpdate = DateTime.Now },
new Stock(24.85M) { Symbol = "INTC", DayOpen=24.9M, LastUpdate = DateTime.Now },
new Stock(22.99M){ Symbol = "CSCO", DayOpen=22.7M, LastUpdate = DateTime.Now },
new Stock(30.71M){ Symbol = "SIRI", DayOpen=30.7M, LastUpdate = DateTime.Now },
new Stock(58.73M){ Symbol = "AAPL", DayOpen=54.9M, LastUpdate = DateTime.Now },
new Stock(110M){ Symbol = "HOKU", DayOpen=121.2M, LastUpdate = DateTime.Now },
new Stock(38.11M){ Symbol = "ORCL", DayOpen=37.9M, LastUpdate = DateTime.Now },
new Stock(17.61M) { Symbol = "AMAT", DayOpen=17.5M, LastUpdate = DateTime.Now },
new Stock(40.80M){ Symbol = "YHOO", DayOpen=39.9M, LastUpdate = DateTime.Now },
new Stock(31.85M){ Symbol = "LVLT", DayOpen=32.9M, LastUpdate = DateTime.Now },
new Stock(20.63M){ Symbol = "DELL", DayOpen=17.9M, LastUpdate = DateTime.Now },
new Stock(63.70M) { Symbol = "GOOG", DayOpen=55.9M, LastUpdate = DateTime.Now }
};
}
private void UpdateStockPrices(object state) {
lock(_updateStockPricesLock) {
foreach(var stock in _stocks) {
if(TryUpdateStockPrice(stock)) {
BroadcastStockPrice(stock);
}
}
}
}
private bool TryUpdateStockPrice(Stock stock) {
var r = _updateOrNotRandom.NextDouble();
if(r > .1) {
return false;
}
stock.Update();
return true;
}
private void BroadcastStockPrice(Stock stock) {
Clients.All.updateStockPrice(stock);
}
}
}
using System;
using DevExpress.Data.Utils;
namespace DevExtreme.MVC.Demos.Models.SignalR {
public class Stock {
readonly decimal _initPrice;
public Stock(decimal price) {
Price = price;
DayMax = price;
DayMin = price;
_initPrice = Price;
}
public string Symbol { get; set; }
public decimal Price { get; set; }
public decimal DayMax { get; set; }
public decimal DayMin { get; set; }
public decimal DayOpen { get; set; }
public DateTime LastUpdate { get; set; }
public decimal Change {
get {
return Price - DayOpen;
}
}
public double PercentChange {
get {
return (double)Math.Round(Change * 100 / DayOpen, 2);
}
}
public void Update() {
var isNewDay = LastUpdate.Day != DateTime.Now.Day;
var change = GenerateChange();
var newPrice = _initPrice + _initPrice * change;
Price = newPrice;
LastUpdate = DateTime.Now;
if(Price > DayMax || isNewDay)
DayMax = Price;
if(Price < DayMin || isNewDay)
DayMin = Price;
}
static NonCryptographicRandom random = NonCryptographicRandom.System;
decimal GenerateChange() {
return (decimal)random.Next(-200, 200) / 10000;
}
}
}
For more information about integration with push services, refer to the following help topic: Integration with Push Services.
Data used in this demo is for demonstration purposes only.