Lazy-Loading and OData

This example shows how you can use the TreeView control to display hierarchical data from OData sources.

import 'bootstrap.css'; import '@grapecity/wijmo.styles/wijmo.css'; import './styles.css'; import * as wjNav from '@grapecity/wijmo.nav'; import * as wjOdata from '@grapecity/wijmo.odata'; import * as wjCore from '@grapecity/wijmo'; // document.readyState === 'complete' ? init() : window.onload = init; // function init() { // // NorthWind service URL var nwindService = 'https://services.odata.org/Northwind/Northwind.svc'; // // create the tree var tree = new wjNav.TreeView('#theTree', { displayMemberPath: ['FullName', 'ShipName', 'Summary'], childItemsPath: ['Orders', 'Order_Details'], lazyLoadFunction: lazyLoadODataFunction, }); // // get employee list var view = new wjOdata.ODataCollectionView(nwindService, 'Employees', { fields: 'EmployeeID,FirstName,LastName'.split(','), loaded: function (s, e) { // // when the data is loaded, add FullName and Orders array to employees var items = s.items.map(function (employee) { employee.FullName = employee.FirstName + ' ' + employee.LastName; employee.Orders = []; // lazy-load orders }); // // populate the tree with the employees array tree.itemsSource = s.items; } }); // // lazy-load orders and details function lazyLoadODataFunction(node, callback) { switch (node.level) { // // load orders for an employee case 0: var url = 'Employees(' + node.dataItem.EmployeeID + ')/Orders'; var orders = new wjOdata.ODataCollectionView(nwindService, url, { fields: 'OrderID,ShipName,ShipCountry'.split(','), loaded: function () { var items = orders.items.map(function (e) { e.Order_Details = []; // lazy-order details return e; }); callback(items); } }); break; // // load extended details for an order case 1: var url = "Order_Details_Extendeds?$filter=OrderID eq " + node.dataItem.OrderID; var details = new wjOdata.ODataCollectionView(nwindService, url, { fields: 'ProductName,ExtendedPrice'.split(','), loaded: function () { var items = details.items.map(function (e) { e.Summary = wjCore.format('{ProductName}: {ExtendedPrice:c}', e); return e; }); callback(items); } }); break; // // default default: callback(null); } } }
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <title>GrapeCity Wijmo TreeView Lazy Loading OData</title> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <!-- SystemJS --> <script src="node_modules/systemjs/dist/system.src.js"></script> <script src="systemjs.config.js"></script> <script> System.import('./src/app'); </script> </head> <body> <div class="container-fluid"> <div id="theTree"></div> </div> </body> </html>
/* level 0 nodes and deeper (employees...) */ .wj-treeview .wj-nodelist > .wj-node { font-weight: bold; } /* level 1 nodes and deeper (orders...) */ .wj-treeview .wj-nodelist > .wj-nodelist > .wj-node { font-weight: normal; font-size: 95%; color: darkblue; } /* level 2 nodes and deeper (order details...) */ .wj-treeview .wj-nodelist > .wj-nodelist > .wj-nodelist > .wj-node { font-size: 90%; color: darkslategrey; } /* default trees on this sample */ .wj-treeview { display:block; height: 350px; font-size: 120%; margin-top: 8px; margin-bottom: 8px; padding: 6px; background: #f0f0f0; box-shadow: 0 3px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23); } body { margin-bottom: 24pt; }
(function (global) { System.config({ transpiler: 'plugin-babel', babelOptions: { es2015: true }, meta: { '*.css': { loader: 'css' } }, paths: { // paths serve as alias 'npm:': 'node_modules/' }, // map tells the System loader where to look for things map: { 'jszip': 'npm:jszip/dist/jszip.js', '@grapecity/wijmo': 'npm:@grapecity/wijmo/index.js', '@grapecity/wijmo.input': 'npm:@grapecity/wijmo.input/index.js', '@grapecity/wijmo.styles': 'npm:@grapecity/wijmo.styles', '@grapecity/wijmo.cultures': 'npm:@grapecity/wijmo.cultures', '@grapecity/wijmo.chart': 'npm:@grapecity/wijmo.chart/index.js', '@grapecity/wijmo.chart.analytics': 'npm:@grapecity/wijmo.chart.analytics/index.js', '@grapecity/wijmo.chart.animation': 'npm:@grapecity/wijmo.chart.animation/index.js', '@grapecity/wijmo.chart.annotation': 'npm:@grapecity/wijmo.chart.annotation/index.js', '@grapecity/wijmo.chart.finance': 'npm:@grapecity/wijmo.chart.finance/index.js', '@grapecity/wijmo.chart.finance.analytics': 'npm:@grapecity/wijmo.chart.finance.analytics/index.js', '@grapecity/wijmo.chart.hierarchical': 'npm:@grapecity/wijmo.chart.hierarchical/index.js', '@grapecity/wijmo.chart.interaction': 'npm:@grapecity/wijmo.chart.interaction/index.js', '@grapecity/wijmo.chart.radar': 'npm:@grapecity/wijmo.chart.radar/index.js', '@grapecity/wijmo.chart.render': 'npm:@grapecity/wijmo.chart.render/index.js', '@grapecity/wijmo.chart.webgl': 'npm:@grapecity/wijmo.chart.webgl/index.js', '@grapecity/wijmo.gauge': 'npm:@grapecity/wijmo.gauge/index.js', '@grapecity/wijmo.grid': 'npm:@grapecity/wijmo.grid/index.js', '@grapecity/wijmo.grid.detail': 'npm:@grapecity/wijmo.grid.detail/index.js', '@grapecity/wijmo.grid.filter': 'npm:@grapecity/wijmo.grid.filter/index.js', '@grapecity/wijmo.grid.search': 'npm:@grapecity/wijmo.grid.search/index.js', '@grapecity/wijmo.grid.grouppanel': 'npm:@grapecity/wijmo.grid.grouppanel/index.js', '@grapecity/wijmo.grid.multirow': 'npm:@grapecity/wijmo.grid.multirow/index.js', '@grapecity/wijmo.grid.transposed': 'npm:@grapecity/wijmo.grid.transposed/index.js', '@grapecity/wijmo.grid.transposedmultirow': 'npm:@grapecity/wijmo.grid.transposedmultirow/index.js', '@grapecity/wijmo.grid.pdf': 'npm:@grapecity/wijmo.grid.pdf/index.js', '@grapecity/wijmo.grid.sheet': 'npm:@grapecity/wijmo.grid.sheet/index.js', '@grapecity/wijmo.grid.xlsx': 'npm:@grapecity/wijmo.grid.xlsx/index.js', '@grapecity/wijmo.grid.selector': 'npm:@grapecity/wijmo.grid.selector/index.js', '@grapecity/wijmo.grid.cellmaker': 'npm:@grapecity/wijmo.grid.cellmaker/index.js', '@grapecity/wijmo.nav': 'npm:@grapecity/wijmo.nav/index.js', '@grapecity/wijmo.odata': 'npm:@grapecity/wijmo.odata/index.js', '@grapecity/wijmo.olap': 'npm:@grapecity/wijmo.olap/index.js', '@grapecity/wijmo.pdf': 'npm:@grapecity/wijmo.pdf/index.js', '@grapecity/wijmo.pdf.security': 'npm:@grapecity/wijmo.pdf.security/index.js', '@grapecity/wijmo.viewer': 'npm:@grapecity/wijmo.viewer/index.js', '@grapecity/wijmo.xlsx': 'npm:@grapecity/wijmo.xlsx/index.js', '@grapecity/wijmo.undo': 'npm:@grapecity/wijmo.undo/index.js', '@grapecity/wijmo.interop.grid': 'npm:@grapecity/wijmo.interop.grid/index.js', '@grapecity/wijmo.touch': 'npm:@grapecity/wijmo.touch/index.js', '@grapecity/wijmo.cloud': 'npm:@grapecity/wijmo.cloud/index.js', '@grapecity/wijmo.barcode': 'npm:@grapecity/wijmo.barcode/index.js', '@grapecity/wijmo.barcode.common': 'npm:@grapecity/wijmo.barcode.common/index.js', '@grapecity/wijmo.barcode.composite': 'npm:@grapecity/wijmo.barcode.composite/index.js', '@grapecity/wijmo.barcode.specialized': 'npm:@grapecity/wijmo.barcode.specialized/index.js', 'jszip': 'npm:jszip/dist/jszip.js', 'bootstrap.css': 'npm:bootstrap/dist/css/bootstrap.min.css', 'css': 'npm:systemjs-plugin-css/css.js', 'plugin-babel': 'npm:systemjs-plugin-babel/plugin-babel.js', 'systemjs-babel-build':'npm:systemjs-plugin-babel/systemjs-babel-browser.js' }, // packages tells the System loader how to load when no filename and/or no extension packages: { src: { defaultExtension: 'js' }, "node_modules": { defaultExtension: 'js' }, } }); })(this);