added loading spinner for when graph is loading

src/app/dashboard/more-graphs-and-tables.component.html

@@ -5,13 +5,15 @@
         <div class="col-sm-7">
           <h4 class="card-title mb-0">Spend amount and number of purchases by supplier name</h4>
         </div>
-        <div class="col-sm-5 hidden-sm-down">
+        <div class="col-sm-5 hidden-sm-down"  *ngIf="isBubbleChartLoaded">
           <input type="date" [(ngModel)]="bubbleChartBegin" (change)="bubbleChartUpdate()">
-          <!-- THESE INPUT BOXES DO NOT WORK. Their value remains the client machine's date/time despite changing. -->
           <input type="date" [(ngModel)]="bubbleChartEnd" (change)="bubbleChartUpdate()">
         </div>
       </div>
-      <div>
+      <div class="col-sm-7"  *ngIf="!isBubbleChartLoaded">
+        <div class="spinner"></div>
+      </div>
+      <div *ngIf="isBubbleChartLoaded">
         <canvas baseChart
                 [datasets]="supplierBubbleChartData"
                 [options]="supplierBubbleChartOptions"
@@ -28,10 +30,6 @@
         <div class="col-sm-7">
           <h4 class="card-title mb-0">Spend amount and number of organisations</h4>
         </div>
-        <div class="col-sm-5 hidden-sm-down">
-    <!--      <input type="date" id="yearSpendChartBegin" name="yearSpendChartBegin" ng-model="yearSpendChartBegin" ng-change="yearSpendChartBegin"> -->
-    <!--      <input type="date" id="yearSpendChartEnd" name="yearSpendChartEnd" ng-model="yearSpendChartEnd" ng-change="yearSpendChartEnd"> -->
-        </div>
       </div>
       <div>
         <canvas baseChart

src/app/dashboard/more-graphs-and-tables.component.ts

@@ -15,6 +15,7 @@ export class MoreStuffComponent implements OnInit {
   bubbleChartBegin: any;
   bubbleChartEnd: any;
   cached_graph_data: any;
+  isBubbleChartLoaded = false;
 
   constructor(
     private api: ApiService,
@@ -26,7 +27,7 @@ export class MoreStuffComponent implements OnInit {
 
   ngOnInit(): void {
     this.loadYearSpend();
-   this.loadSupplierBubble(false, ('January 1, 2018'), ('January 1, 2019')); // pass start and end date ranges to this as Date()s
+    this.loadSupplierBubble(false, ('0'), ('0'));
     this.loadSupplierHistory();
   }
 
@@ -104,12 +105,11 @@ export class MoreStuffComponent implements OnInit {
   }
 
   private loadSupplierBubble(useRange: boolean, start_range : string, end_range : string) {
-    console.log("Fetching data for bubble chart... this will take a while. custom range = " + useRange);
+    this.isBubbleChartLoaded = false;
+    // console.log("Fetching data for bubble chart... this will take a while. custom range = " + useRange);
 
     var is_cached = false;
 
-    console.log(this.cached_graph_data);
-
     try {
       if (this.cached_graph_data) {
         is_cached = true;
@@ -121,6 +121,8 @@ export class MoreStuffComponent implements OnInit {
     if (is_cached) {
       console.log("Using cached data of " + this.cached_graph_data.length + " items.");
       this.supplierBubbleChartData[0].data = this.formatGraphData(this.cached_graph_data, useRange, start_range, end_range);
+      this.isBubbleChartLoaded = true;
+      console.log("variable \"this.isBubbleChartLoaded\": " + this.isBubbleChartLoaded);
     }
     else {
       console.log("Not using cached data.");
@@ -130,10 +132,13 @@ export class MoreStuffComponent implements OnInit {
   
           this.supplierBubbleChartData[0].data = this.formatGraphData(result, useRange, start_range, end_range);
           console.log("Graph fetched with " + this.supplierBubbleChartData[0].data.length + " items.");
+          this.isBubbleChartLoaded = true;
+          console.log("variable \"this.isBubbleChartLoaded\": " + this.isBubbleChartLoaded);
         }
       )
     }
 
+    console.log("variable \"this.isBubbleChartLoaded\": " + this.isBubbleChartLoaded);
   }
 
   public supplierBubbleChartType: ChartType = 'bubble';
@@ -215,6 +220,8 @@ export class MoreStuffComponent implements OnInit {
 
   // this is called when daterange is changed
     this.loadSupplierBubble(true, (this.bubbleChartBegin), (this.bubbleChartEnd));
+
+    console.log("variable \"this.isBubbleChartLoaded\": " + this.isBubbleChartLoaded);
   /*
     bubbleChartBegin: any;
     bubbleChartEnd: any;

src/scss/bootstrap/_spinner.scss

@@ -0,0 +1,28 @@
+.spinner {
+    width: 40px;
+    height: 40px;
+    background-color: #333;
+  
+    margin: 100px auto;
+    -webkit-animation: sk-rotateplane 1.2s infinite ease-in-out;
+    animation: sk-rotateplane 1.2s infinite ease-in-out;
+  }
+  
+  @-webkit-keyframes sk-rotateplane {
+    0% { -webkit-transform: perspective(120px) }
+    50% { -webkit-transform: perspective(120px) rotateY(180deg) }
+    100% { -webkit-transform: perspective(120px) rotateY(180deg)  rotateX(180deg) }
+  }
+  
+  @keyframes sk-rotateplane {
+    0% { 
+      transform: perspective(120px) rotateX(0deg) rotateY(0deg);
+      -webkit-transform: perspective(120px) rotateX(0deg) rotateY(0deg) 
+    } 50% { 
+      transform: perspective(120px) rotateX(-180.1deg) rotateY(0deg);
+      -webkit-transform: perspective(120px) rotateX(-180.1deg) rotateY(0deg) 
+    } 100% { 
+      transform: perspective(120px) rotateX(-180deg) rotateY(-179.9deg);
+      -webkit-transform: perspective(120px) rotateX(-180deg) rotateY(-179.9deg);
+    }
+  }

src/scss/style.scss

@@ -76,3 +76,4 @@
 
 // Custom styles
 @import "custom";
+@import "bootstrap/spinner";