Fix

dist/ngx-flowchart/bundles/ngx-flowchart.umd.js

 (function (global, factory) {
-    typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('@angular/core'), require('rxjs'), require('@angular/common')) :
-    typeof define === 'function' && define.amd ? define('ngx-flowchart', ['exports', '@angular/core', 'rxjs', '@angular/common'], factory) :
-    (global = global || self, factory(global['ngx-flowchart'] = {}, global.ng.core, global.rxjs, global.ng.common));
-}(this, (function (exports, core, rxjs, common) { 'use strict';
+    typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('@angular/core'), require('rxjs'), require('rxjs/operators'), require('@angular/common')) :
+    typeof define === 'function' && define.amd ? define('ngx-flowchart', ['exports', '@angular/core', 'rxjs', 'rxjs/operators', '@angular/common'], factory) :
+    (global = global || self, factory(global['ngx-flowchart'] = {}, global.ng.core, global.rxjs, global.rxjs.operators, global.ng.common));
+}(this, (function (exports, core, rxjs, operators, common) { 'use strict';
 
     /*! *****************************************************************************
     Copyright (c) Microsoft Corporation. All rights reserved.
@@ -548,11 +548,13 @@
      */
     var FcModelService = /** @class */ (function () {
         function FcModelService(modelValidation, model, modelChanged, cd, selectedObjects, dropNode, createEdge, edgeAddedCallback, nodeRemovedCallback, edgeRemovedCallback, canvasHtmlElement, svgHtmlElement) {
+            var _this = this;
             this.connectorsHtmlElements = {};
             this.nodesHtmlElements = {};
             this.canvasHtmlElement = null;
             this.dragImage = null;
             this.svgHtmlElement = null;
+            this.debouncer = new rxjs.Subject();
             this.modelValidation = modelValidation;
             this.model = model;
             this.modelChanged = modelChanged;
@@ -586,6 +588,12 @@
             this.connectors = new ConnectorsModel(this);
             this.nodes = new NodesModel(this);
             this.edges = new EdgesModel(this);
+            this.debouncer
+                .pipe(operators.debounceTime(100))
+                .subscribe((/**
+             * @return {?}
+             */
+            function () { return _this.modelChanged.emit(); }));
         }
         /**
          * @return {?}
@@ -594,7 +602,7 @@
          * @return {?}
          */
         function () {
-            this.modelChanged.emit();
+            this.debouncer.next();
         };
         /**
          * @return {?}
@@ -985,8 +993,16 @@
         FcModelService.prototype.edgeRemovedCallback;
         /** @type {?} */
         FcModelService.prototype.dropTargetId;
-        /** @type {?} */
+        /**
+         * @type {?}
+         * @private
+         */
         FcModelService.prototype.modelChanged;
+        /**
+         * @type {?}
+         * @private
+         */
+        FcModelService.prototype.debouncer;
         /** @type {?} */
         FcModelService.prototype.connectors;
         /** @type {?} */

dist/ngx-flowchart/fesm2015/ngx-flowchart.js

 import { InjectionToken, Injectable, EventEmitter, Component, ChangeDetectionStrategy, ElementRef, IterableDiffers, ChangeDetectorRef, NgZone, HostBinding, Input, Output, HostListener, Directive, Inject, ComponentFactoryResolver, ViewChild, ViewContainerRef, NgModule } from '@angular/core';
-import { of } from 'rxjs';
+import { Subject, of } from 'rxjs';
+import { debounceTime } from 'rxjs/operators';
 import { CommonModule } from '@angular/common';
 
 /**
@@ -346,6 +347,7 @@ class FcModelService {
         this.canvasHtmlElement = null;
         this.dragImage = null;
         this.svgHtmlElement = null;
+        this.debouncer = new Subject();
         this.modelValidation = modelValidation;
         this.model = model;
         this.modelChanged = modelChanged;
@@ -379,12 +381,18 @@ class FcModelService {
         this.connectors = new ConnectorsModel(this);
         this.nodes = new NodesModel(this);
         this.edges = new EdgesModel(this);
+        this.debouncer
+            .pipe(debounceTime(100))
+            .subscribe((/**
+         * @return {?}
+         */
+        () => this.modelChanged.emit()));
     }
     /**
      * @return {?}
      */
     notifyModelChanged() {
-        this.modelChanged.emit();
+        this.debouncer.next();
     }
     /**
      * @return {?}
@@ -686,8 +694,16 @@ if (false) {
     FcModelService.prototype.edgeRemovedCallback;
     /** @type {?} */
     FcModelService.prototype.dropTargetId;
-    /** @type {?} */
+    /**
+     * @type {?}
+     * @private
+     */
     FcModelService.prototype.modelChanged;
+    /**
+     * @type {?}
+     * @private
+     */
+    FcModelService.prototype.debouncer;
     /** @type {?} */
     FcModelService.prototype.connectors;
     /** @type {?} */

dist/ngx-flowchart/fesm5/ngx-flowchart.js

 import { __extends, __values, __assign } from 'tslib';
 import { InjectionToken, Injectable, EventEmitter, Component, ChangeDetectionStrategy, ElementRef, IterableDiffers, ChangeDetectorRef, NgZone, HostBinding, Input, Output, HostListener, Directive, Inject, ComponentFactoryResolver, ViewChild, ViewContainerRef, NgModule } from '@angular/core';
-import { of } from 'rxjs';
+import { Subject, of } from 'rxjs';
+import { debounceTime } from 'rxjs/operators';
 import { CommonModule } from '@angular/common';
 
 /**
@@ -350,11 +351,13 @@ function fcTopSort(graph) {
  */
 var FcModelService = /** @class */ (function () {
     function FcModelService(modelValidation, model, modelChanged, cd, selectedObjects, dropNode, createEdge, edgeAddedCallback, nodeRemovedCallback, edgeRemovedCallback, canvasHtmlElement, svgHtmlElement) {
+        var _this = this;
         this.connectorsHtmlElements = {};
         this.nodesHtmlElements = {};
         this.canvasHtmlElement = null;
         this.dragImage = null;
         this.svgHtmlElement = null;
+        this.debouncer = new Subject();
         this.modelValidation = modelValidation;
         this.model = model;
         this.modelChanged = modelChanged;
@@ -388,6 +391,12 @@ var FcModelService = /** @class */ (function () {
         this.connectors = new ConnectorsModel(this);
         this.nodes = new NodesModel(this);
         this.edges = new EdgesModel(this);
+        this.debouncer
+            .pipe(debounceTime(100))
+            .subscribe((/**
+         * @return {?}
+         */
+        function () { return _this.modelChanged.emit(); }));
     }
     /**
      * @return {?}
@@ -396,7 +405,7 @@ var FcModelService = /** @class */ (function () {
      * @return {?}
      */
     function () {
-        this.modelChanged.emit();
+        this.debouncer.next();
     };
     /**
      * @return {?}
@@ -787,8 +796,16 @@ if (false) {
     FcModelService.prototype.edgeRemovedCallback;
     /** @type {?} */
     FcModelService.prototype.dropTargetId;
-    /** @type {?} */
+    /**
+     * @type {?}
+     * @private
+     */
     FcModelService.prototype.modelChanged;
+    /**
+     * @type {?}
+     * @private
+     */
+    FcModelService.prototype.debouncer;
     /** @type {?} */
     FcModelService.prototype.connectors;
     /** @type {?} */

dist/ngx-flowchart/lib/model.service.d.ts

@@ -18,7 +18,8 @@ export declare class FcModelService {
     nodeRemovedCallback: (node: FcNode) => void;
     edgeRemovedCallback: (edge: FcEdge) => void;
     dropTargetId: string;
-    modelChanged: EventEmitter<any>;
+    private readonly modelChanged;
+    private readonly debouncer;
     connectors: ConnectorsModel;
     nodes: NodesModel;
     edges: EdgesModel;