virtual scroll updates

apps/red-ui/src/app/app.module.ts

@@ -86,6 +86,7 @@ import { DictionaryListingScreenComponent } from './screens/admin/dictionary-lis
 import { CustomTooltipModule } from './common/red-tooltip/custom-tooltip.module';
 import { ScrollingModule } from '@angular/cdk/scrolling';
 import { VirtualScrollComponent } from './utils/virtual-scroll/virtual-scroll.component';
+import { DragDropModule } from '@angular/cdk/drag-drop';
 
 export function HttpLoaderFactory(httpClient: HttpClient) {
     return new TranslateHttpLoader(httpClient, '/assets/i18n/', '.json');
@@ -237,7 +238,8 @@ export function HttpLoaderFactory(httpClient: HttpClient) {
         MatCheckboxModule,
         MatListModule,
         MatDatepickerModule,
-        MatInputModule
+        MatInputModule,
+        DragDropModule
     ],
     providers: [
         {

apps/red-ui/src/app/utils/virtual-scroll/virtual-scroll.component.html

@@ -1,3 +1,13 @@
-<div class="virtual-scroll" #scrollElement>
-    <div class="virtual" [style.height]="height + 'px'"></div>
+<div class="virtual-scroll" #scrollElement (click)="scrollClicked($event)">
+    <div
+        class="scroller"
+        [style.height]="height + 'px'"
+        cdkDragBoundary=".virtual-scroll"
+        cdkDrag
+        #scroller
+        (cdkDragMoved)="moved($event)"
+        (cdkDragReleased)="released($event)"
+        (cdkDragStarted)="started($event)"
+        (click)="$event.stopPropagation()"
+    ></div>
 </div>

apps/red-ui/src/app/utils/virtual-scroll/virtual-scroll.component.scss

@@ -1,6 +1,7 @@
+@import '../../../assets/styles/red-variables';
+
 .virtual-scroll {
     // TODO fix this - pass information as input or such
-    display: none;
     position: fixed;
     width: 10px;
     right: 480px;
@@ -8,8 +9,17 @@
     z-index: 100;
     top: 191px;
     overflow: auto;
+    background: $grey-6;
 
-    .virtual {
-        height: 2000px;
+    .scroller {
+        position: absolute;
+        height: 50px;
+        width: 10px;
+        background: $grey-5;
+        transition: transform 0.1s ease 0s, background 0.25s ease;
+
+        &:hover {
+            background: $grey-7;
+        }
     }
 }

apps/red-ui/src/app/utils/virtual-scroll/virtual-scroll.component.ts

@@ -1,5 +1,5 @@
 import { AfterViewInit, Component, ElementRef, Input, ViewChild } from '@angular/core';
-import { syncScroll } from '../sync-scroll';
+import { CdkDragMove, CdkDragRelease, CdkDragStart } from '@angular/cdk/drag-drop';
 
 @Component({
     selector: 'redaction-virtual-scroll',
@@ -10,17 +10,57 @@ export class VirtualScrollComponent implements AfterViewInit {
     @Input() targetQuerySelector = '.red-content';
     @ViewChild('scrollElement')
     scrollElement: ElementRef;
+    @ViewChild('scroller')
+    scroller: ElementRef;
     content: HTMLElement;
-    height: number;
     factor: number;
+    height: number;
+    listener = () => {
+        console.log('adjust', this.content.scrollTop);
+        const top = Math.min(this.content.scrollTop * this.factor, this.scrollElement.nativeElement.clientHeight - this.height);
+        this.scroller.nativeElement.style.transform = 'translate3d(0px,' + top + 'px, 0px)';
+    };
 
     constructor() {}
 
     ngAfterViewInit(): void {
         this.content = document.querySelector(this.targetQuerySelector);
         this.factor = this.content.clientHeight / this.scrollElement.nativeElement.clientHeight;
-        this.height = Math.round(this.content.scrollHeight / this.factor);
-        console.log(this.factor, this.height);
-        syncScroll([this.scrollElement.nativeElement, this.content]);
+        const scrollFactor = this.content.scrollHeight / this.content.clientHeight;
+        this.height = this.scrollElement.nativeElement.clientHeight / scrollFactor;
+        this.content.addEventListener('scroll', this.listener);
+    }
+
+    scrollClicked($event: MouseEvent) {
+        console.log('clicked');
+        // half the scroll bar size - center pos ->
+        const top = Math.min(Math.max(0, $event.offsetY - this.height / 2), this.scrollElement.nativeElement.clientHeight - this.height);
+        this.scroller.nativeElement.style.transform = 'translate3d(0px,' + top + 'px, 0px)';
+        this.content.removeEventListener('scroll', this.listener);
+        this.content.scrollTop = top * this.factor;
+        console.log(this.content.scrollTop, top, this.factor);
+        this.content.addEventListener('scroll', this.listener);
+    }
+
+    released($event: CdkDragRelease) {
+        this.content.addEventListener('scroll', this.listener);
+    }
+
+    started($event: CdkDragStart) {
+        this.content.removeEventListener('scroll', this.listener);
+    }
+
+    moved($event: CdkDragMove<any>) {
+        console.log('moveded', this._getTop());
+    }
+
+    private _getTop() {
+        const translateY = this.scroller.nativeElement.style.transform
+            .split('translate3d')
+            .filter((t) => t.trim().length > 0)
+            .map((t) => t.split(',')[1].trim().replace('px', ''))
+            .map((t) => parseInt(t, 10))
+            .reduce((acc, el) => acc + el, 0);
+        this.content.scrollTop = translateY * this.factor;
     }
 }