add sorting for gallery

pdb-js/src/app/image-toggle/image-toggle.component.ts

@@ -0,0 +1,38 @@
+import { Component, OnInit, Input, Output, EventEmitter } from '@angular/core';
+
+@Component({
+  selector: 'pdb-image-toggle',
+  templateUrl: './image-toggle.component.html',
+  styleUrls: ['./image-toggle.component.scss']
+})
+export class ImageToggleComponent implements OnInit {
+
+  @Input()
+  images : string = "";
+  
+  value: number = 0;
+  
+  @Output()
+  valueChanged : EventEmitter<number> = new EventEmitter<number>();
+  
+  _states : Array<any>;
+
+  constructor() { }
+
+  ngOnInit() {
+    this._states = JSON.parse(this.images);
+  }
+  
+  imageUrl() : string {
+    return this._states[this.value].imageUrl;
+  }
+  
+  title() : string {
+    return this._states[this.value].title;
+  }
+
+  toggle(event){
+    this.value = (this.value+1) % this._states.length;
+    this.valueChanged.emit(this.value);
+  }
+}