Resolve "Bug unselect all outputs"

Closes #63 (closed)

src/app/search/components/output/output-by-category.component.ts

 import { Component, Input, Output, EventEmitter, ChangeDetectionStrategy } from '@angular/core';
 
+import { ToastrService } from 'ngx-toastr';
 import { Attribute } from '../../../metamodel/model';
 
 @Component({
@@ -11,10 +12,20 @@ import { Attribute } from '../../../metamodel/model';
 export class OutputByCategoryComponent {
     @Input() categoryLabel: string;
     @Input() attributeList: Attribute[];
-    @Input() outputList: number[];
+    // @Input() outputList: number[];
+    @Input() set outputList(outputList: number[]) {
+        this._outputList = outputList;
+        if (outputList.length === 0) {
+            this.toastr.warning('At least 1 output is required!');
+        }
+    }
     @Input() isAllSelected: boolean;
     @Input() isAllUnselected: boolean;
     @Output() change: EventEmitter<number[]> = new EventEmitter();
+    public _outputList: number[];
+
+
+    constructor(private toastr: ToastrService) { }
 
     getAttributeListSortedByDisplay() {
         return this.attributeList
@@ -22,11 +33,11 @@ export class OutputByCategoryComponent {
     }
 
     isSelected(id: number) {
-        return this.outputList.filter(i => i === id).length > 0;
+        return this._outputList.filter(i => i === id).length > 0;
     }
 
     toggleSelection(attributeId: number): void {
-        const clonedOutputList = [...this.outputList];
+        const clonedOutputList = [...this._outputList];
         const index = clonedOutputList.indexOf(attributeId);
         if (index > -1) {
             clonedOutputList.splice(index, 1);
@@ -37,7 +48,7 @@ export class OutputByCategoryComponent {
     }
 
     selectAll(): void {
-        const clonedOutputList = [...this.outputList];
+        const clonedOutputList = [...this._outputList];
         const attributeListId = this.attributeList.map(a => a.id);
         attributeListId.filter(id => clonedOutputList.indexOf(id) === -1).forEach(id => {
             clonedOutputList.push(id);
@@ -46,7 +57,7 @@ export class OutputByCategoryComponent {
     }
 
     unselectAll(): void {
-        const clonedOutputList = [...this.outputList];
+        const clonedOutputList = [...this._outputList];
         const attributeListId = this.attributeList.map(a => a.id);
         attributeListId.filter(id => clonedOutputList.indexOf(id) > -1).forEach(id => {
             const index = clonedOutputList.indexOf(id);