Real-Time Updates
The DataGrid component is optimized for real-time updates. You should bind it to a DataSource that contains a store and use the push(changes) method to update the store's data. The rows with changed data are rerendered (see the DataGrid's repaintChangesOnly property). The DataSource object also provides properties that control its behavior when it receives a push. For example, reshapeOnPush is set to true in this demo to allow summaries to be recalculated.
Grids in the detail sections are updated in real time as well. All the grids share the same ordersStore that receives pushes, but it is filtered to show only a specific product's orders for each grid.
Feel free to share demo-related thoughts here.
If you have technical questions, please create a support ticket in the DevExpress Support Center.
Thank you for the feedback!
If you have technical questions, please create a support ticket in the DevExpress Support Center.
Backend API
$(() => {
$('#grid-container').dxDataGrid({
dataSource: {
store: productsStore,
reshapeOnPush: true,
},
repaintChangesOnly: true,
columnAutoWidth: true,
showBorders: true,
paging: {
pageSize: 10,
},
columns: [
{ dataField: 'ProductName', dataType: 'string' },
{ dataField: 'UnitPrice', dataType: 'number', format: 'currency' },
{ dataField: 'OrderCount', dataType: 'number' },
{ dataField: 'Quantity', dataType: 'number' },
{
dataField: 'Amount', dataType: 'number', format: 'currency', allowSorting: true,
},
],
summary: {
totalItems: [{
summaryType: 'count',
column: 'ProductName',
}, {
summaryType: 'sum',
displayFormat: '{0}',
valueFormat: 'currency',
column: 'Amount',
}, {
summaryType: 'sum',
displayFormat: '{0}',
column: 'OrderCount',
}],
},
masterDetail: {
enabled: true,
template(container, options) {
$('<div>').appendTo(container).dxDataGrid({
dataSource: {
store: ordersStore,
filter: ['ProductID', '=', options.key],
reshapeOnPush: true,
},
repaintChangesOnly: true,
columnAutoWidth: true,
showBorders: true,
paging: {
pageSize: 5,
},
columns: [{
dataField: 'OrderID',
dataType: 'number',
}, {
dataField: 'ShipCity',
dataType: 'string',
}, {
dataField: 'OrderDate',
dataType: 'datetime',
format: 'yyyy/MM/dd HH:mm:ss',
}, {
dataField: 'UnitPrice',
dataType: 'number',
}, {
dataField: 'Quantity',
dataType: 'number',
}, {
caption: 'Amount',
dataType: 'number',
format: 'currency',
allowSorting: true,
calculateCellValue(rowData) {
return rowData.UnitPrice * rowData.Quantity;
},
}],
summary: {
totalItems: [{
summaryType: 'count',
column: 'OrderID',
}, {
summaryType: 'sum',
displayFormat: '{0}',
column: 'Quantity',
}, {
summaryType: 'sum',
displayFormat: '{0}',
valueFormat: 'currency',
column: 'Amount',
}],
},
});
},
},
});
let updatesPerSecond = 100;
setInterval(() => {
if (orders.length > 500000) {
return;
}
for (let i = 0; i < updatesPerSecond / 20; i += 1) {
addOrder();
}
}, 50);
$('#frequency-slider').dxSlider({
min: 10,
max: 5000,
step: 10,
value: updatesPerSecond,
onValueChanged(e) {
updatesPerSecond = e.value;
},
tooltip: {
enabled: true,
showMode: 'always',
position: 'top',
},
});
});
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<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=1.0" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>window.jQuery || document.write(decodeURIComponent('%3Cscript src="js/jquery.min.js"%3E%3C/script%3E'))</script>
<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/23.1.6/css/dx.light.css" />
<script src="https://cdn3.devexpress.com/jslib/23.1.6/js/dx.all.js"></script>
<script src="data.js"></script>
<link rel="stylesheet" type="text/css" href="styles.css" />
<script src="index.js"></script>
</head>
<body class="dx-viewport">
<div class="demo-container">
<div id="grid-container"></div>
<div class="options">
<div class="caption">Options</div>
<div class="option">
<span>Update frequency (per second):</span>
<div id="frequency-slider"></div>
</div>
</div>
</div>
</body>
</html>
.options {
padding: 20px;
margin-top: 20px;
background-color: rgba(191, 191, 191, 0.15);
}
.caption {
font-weight: 500;
font-size: 18px;
}
.option {
margin-top: 10px;
display: flex;
align-items: center;
}
.option > span {
position: relative;
top: 2px;
margin-right: 10px;
}
.option > .dx-widget {
width: 500px;
display: inline-block;
vertical-align: middle;
}
const cities = ['Los Angeles', 'Denver', 'Bentonville', 'Atlanta', 'Reno', 'Beaver', 'Malibu', 'Phoenix', 'San Diego', 'Little Rock', 'Pasadena', 'Boise', 'San Jose', 'Chatsworth', 'San Fernando', 'South Pasadena', 'San Fernando Valley', 'La Canada', 'St. Louis'];
const orders = [];
const ordersStore = new DevExpress.data.ArrayStore({
key: 'OrderID',
data: orders,
});
const products = [];
for (let i = 1; i <= 100; i += 1) {
products.push({
ProductID: i, ProductName: `Product ${i}`, UnitPrice: Math.floor(Math.random() * 1000) + 1, Quantity: 0, Amount: 0, OrderCount: 0,
});
}
const productsStore = new DevExpress.data.ArrayStore({
key: 'ProductID',
data: products,
});
function addOrder() {
const product = products[Math.round(Math.random() * 99)];
const order = {
OrderID: orders.length ? orders[orders.length - 1].OrderID + 1 : 20001,
ShipCity: cities[Math.round(Math.random() * (cities.length - 1))],
ProductID: product.ProductID,
UnitPrice: product.UnitPrice,
OrderDate: new Date(),
Quantity: Math.round(Math.random() * 20) + 1,
};
ordersStore.push([{ type: 'insert', data: order }]);
productsStore.push([{
type: 'update',
key: order.ProductID,
data: {
OrderCount: product.OrderCount + 1,
Quantity: product.Quantity + order.Quantity,
Amount: product.Amount + order.UnitPrice * order.Quantity,
},
}]);
}