Editing Restrictions
Our Diagram component allows you to restrict edit operations as needed. To prohibit a specific operation, set its corresponding property within the editing property to false.
In this demo, the onRequestEditOperation function implements complex logic to determine whether an operation is allowed. The reason event parameter indicates whether the event is raised by a user action or via a UI update. If a user tries to perform a prohibited action, an error message is displayed.
Feel free to share demo-related thoughts here.
If you have technical questions, please create a support ticket in the DevExpress Support Center.
If you have technical questions, please create a support ticket in the DevExpress Support Center.
Thank you!
We appreciate your feedback.
We appreciate your feedback.
<dx-diagram #diagram id="diagram" (onRequestEditOperation)="requestEditOperationHandler($event)" (onRequestLayoutUpdate)="requestLayoutUpdateHandler($event)">
<dxi-custom-shape
category="items"
[type]="'root'"
baseType="octagon"
[defaultText]="'Development'">
</dxi-custom-shape>
<dxi-custom-shape
category="items"
[type]="'team'"
[title]="'Team'"
baseType="ellipse"
[defaultText]="'Team Name'">
</dxi-custom-shape>
<dxi-custom-shape
category="items"
[type]="'employee'"
[title]="'Employee'"
baseType="rectangle"
[defaultText]="'Employee Name'">
</dxi-custom-shape>
<dxo-nodes [dataSource]="orgItemsDataSource" keyExpr="ID" typeExpr="Type" textExpr="Name" parentKeyExpr="ParentID">
<dxo-auto-layout type="tree"></dxo-auto-layout>
</dxo-nodes>
<dxo-context-toolbox [width]="100" [shapeIconsPerRow]="2" [shapes]="['team', 'employee']">
<dxi-group category="general" title="General"></dxi-group>
</dxo-context-toolbox>
<dxo-toolbox [shapeIconsPerRow]="2">
<dxi-group title="Items" [shapes]="['team', 'employee']"></dxi-group>
</dxo-toolbox>
<dxo-properties-panel visibility="disabled">
</dxo-properties-panel>
</dx-diagram>
import { NgModule, Component, ViewChild, enableProdMode } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { HttpClient, HttpClientModule } from '@angular/common/http';
import { DxDiagramModule, DxDiagramComponent } from 'devextreme-angular';
import notify from 'devextreme/ui/notify';
import { Service } from './app.service';
import ArrayStore from 'devextreme/data/array_store'
import dxDiagram, { dxDiagramConnector } from 'devextreme/ui/diagram';
if(!/localhost/.test(document.location.host)) {
enableProdMode();
}
@Component({
selector: 'demo-app',
templateUrl: 'app/app.component.html',
styleUrls: ['app/app.component.css'],
providers: [Service],
preserveWhitespaces: true
})
export class AppComponent {
@ViewChild(DxDiagramComponent, { static: false }) diagram: DxDiagramComponent;
items: any[];
orgItemsDataSource: ArrayStore;
constructor(service: Service) {
this.items = service.getOrgItems();
this.orgItemsDataSource = new ArrayStore({
key: "ID",
data: this.items
});
}
showToast(text) {
notify({
position: { at: "top", my: "top", of: "#diagram", offset: "0 4" },
message: text,
type: "warning",
delayTime: 2000
});
}
requestLayoutUpdateHandler(e) {
for(var i = 0; i < e.changes.length; i++) {
if(e.changes[i].type === 'remove')
e.allowed = true;
else if(e.changes[i].data.ParentID !== undefined && e.changes[i].data.ParentID !== null)
e.allowed = true;
}
}
requestEditOperationHandler(e) {
var diagram = this.diagram.instance;
if(e.operation === "addShape") {
if(e.args.shape.type !== "employee" && e.args.shape.type !== "team") {
if(e.reason !== "checkUIElementAvailability")
this.showToast("You can add only a 'Team' or 'Employee' shape.");
e.allowed = false;
}
}
else if(e.operation === "deleteShape") {
if(e.args.shape.type === "root") {
if(e.reason !== "checkUIElementAvailability")
this.showToast("You cannot delete the 'Development' shape.");
e.allowed = false;
}
if(e.args.shape.type === "team") {
for(var i = 0; i < e.args.shape.attachedConnectorIds.length; i++) {
if(diagram.getItemById(e.args.shape.attachedConnectorIds[i]).toId != e.args.shape.id) {
if(e.reason !== "checkUIElementAvailability")
this.showToast("You cannot delete a 'Team' shape that has a child shape.");
e.allowed = false;
break;
}
}
}
}
else if(e.operation === "resizeShape") {
if(e.args.newSize.width < 1 || e.args.newSize.height < 0.75) {
if(e.reason !== "checkUIElementAvailability")
this.showToast("The shape size is too small.");
e.allowed = false;
}
}
else if(e.operation === "changeConnection") {
var shapeType = e.args.newShape && e.args.newShape.type;
if(shapeType === "root" && e.args.connectorPosition === "end") {
if(e.reason !== "checkUIElementAvailability")
this.showToast("The 'Development' shape cannot have an incoming connection.");
e.allowed = false;
}
if(shapeType === "employee" && e.args.connectorPosition === "start") {
e.allowed = false;
}
}
else if(e.operation === "changeConnectorPoints") {
if(e.args.newPoints.length > 2) {
if(e.reason !== "checkUIElementAvailability")
this.showToast("You cannot add points to a connector.");
e.allowed = false;
}
}
else if(e.operation === "beforeChangeShapeText") {
if(e.args.shape.type === "root") {
if(e.reason !== "checkUIElementAvailability")
this.showToast("You cannot change the 'Development' shape's text.");
e.allowed = false;
}
}
else if(e.operation === "changeShapeText") {
if(e.args.text === "") {
if(e.reason !== "checkUIElementAvailability")
this.showToast("A shape text cannot be empty.");
e.allowed = false;
}
}
else if(e.operation === "beforeChangeConnectorText") {
e.allowed = false;
}
}
}
@NgModule({
imports: [
BrowserModule,
HttpClientModule,
DxDiagramModule
],
declarations: [AppComponent],
bootstrap: [AppComponent]
})
export class AppModule { }
platformBrowserDynamic().bootstrapModule(AppModule);
::ng-deep #diagram {
height: 600px;
}
import { Injectable } from '@angular/core';
export class OrgItem {
ID: string;
Name: string;
Type?: string;
ParentID?: string;
}
let orgItems: OrgItem[] = [
{
"ID":"106",
"Name":"Development",
"Type":"root"
},
{
"ID":"107",
"Name":"WinForms Team",
"Type": "team",
"ParentID": "106"
},
{
"ID":"109",
"Name":"Javascript Team",
"Type": "team",
"ParentID": "106"
},
{
"ID":"110",
"Name":"ASP.NET Team",
"Type": "team",
"ParentID": "106"
},
{
"ID":"112",
"Name": "Ana Trujillo",
"Type": "employee",
"ParentID": "107"
},
{
"ID":"113",
"Name":"Antonio Moreno",
"Type": "employee",
"ParentID": "107"
},
{
"ID":"115",
"Name":"Christina Berglund",
"Type": "employee",
"ParentID": "109"
},
{
"ID":"116",
"Name":"Hanna Moos",
"Type": "employee",
"ParentID": "109"
},
{
"ID":"119",
"Name":"Laurence Lebihan",
"Type": "employee",
"ParentID": "110"
},
{
"ID":"122",
"Name": "Patricio Simpson",
"Type": "employee",
"ParentID": "110"
},
{
"ID":"123",
"Name":"Francisco Chang",
"Type": "employee",
"ParentID": "110"
}
];
@Injectable()
export class Service {
getOrgItems() {
return orgItems;
}
}
// In real applications, you should not transpile code in the browser. You can see how to create your own application with Angular and DevExtreme here:
// https://js.devexpress.com/Documentation/Guide/Angular_Components/Getting_Started/Create_a_DevExtreme_Application/
System.config({
transpiler: 'ts',
typescriptOptions: {
module: "system",
emitDecoratorMetadata: true,
experimentalDecorators: true
},
meta: {
'typescript': {
"exports": "ts"
},
'devextreme/localization.js': {
"esModule": true
}
},
paths: {
'npm:': 'https://unpkg.com/'
},
map: {
'ts': 'npm:plugin-typescript@8.0.0/lib/plugin.js',
'typescript': 'npm:typescript@3.5.3/lib/typescript.js',
'@angular': 'npm:@angular',
'tslib': 'npm:tslib@2.1.0/tslib.js',
'rxjs': 'npm:rxjs@6.4.0',
'rrule': 'npm:rrule@2.6.6/dist/es5/rrule.js',
'luxon': 'npm:luxon@1.26.0/build/global/luxon.min.js',
'es6-object-assign': 'npm:es6-object-assign@1.1.0',
'devextreme': 'npm:devextreme@20.2.6',
'jszip': 'npm:jszip@3.6.0/dist/jszip.min.js',
'devextreme-quill': 'npm:devextreme-quill@0.10.3/dist/dx-quill.min.js',
'devexpress-diagram': 'npm:devexpress-diagram@2.0.18',
'devexpress-gantt': 'npm:devexpress-gantt@2.0.24',
'devextreme-angular': 'npm:devextreme-angular@20.2.6',
'preact': 'npm:preact@10.5.13/dist/preact.js',
'preact/hooks': 'npm:preact@10.5.13/hooks/dist/hooks.js'
},
packages: {
'app': {
main: './app.component.ts',
defaultExtension: 'ts'
},
'devextreme': {
defaultExtension: 'js'
},
'devextreme/events/utils': {
main: 'index'
},
'devextreme/events': {
main: 'index'
},
'es6-object-assign': {
main: './index.js',
defaultExtension: 'js'
}
},
packageConfigPaths: [
"npm:@angular/*/package.json",
"npm:@angular/common/*/package.json",
"npm:rxjs/package.json",
"npm:rxjs/operators/package.json",
"npm:devextreme-angular/*/package.json",
"npm:devextreme-angular/ui/*/package.json",
"npm:devextreme-angular/package.json",
"npm:devexpress-diagram/package.json",
"npm:devexpress-gantt/package.json",
]
});
<!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" />
<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/20.2.6/css/dx.common.css" />
<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/20.2.6/css/dx.light.css" />
<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/20.2.6/css/dx-diagram.css" />
<script src="https://unpkg.com/core-js@2.4.1/client/shim.min.js"></script>
<script src="https://unpkg.com/zone.js@0.10.2/dist/zone.js"></script>
<script src="https://unpkg.com/reflect-metadata@0.1.3/Reflect.js"></script>
<script src="https://unpkg.com/systemjs@0.21.3/dist/system.js"></script>
<script src="config.js"></script>
<script>
System.import('app').catch(console.error.bind(console));
</script>
</head>
<body class="dx-viewport">
<div class="demo-container">
<demo-app>Loading...</demo-app>
</div>
</body>
</html>