Feature: customizable fields display for documents, saved views & dashboard widgets (#6439)

src-ui/src/app/components/common/input/drag-drop-select/drag-drop-select.component.ts

@@ -0,0 +1,68 @@
+import { Component, Input, ViewChild, forwardRef } from '@angular/core'
+import { NG_VALUE_ACCESSOR } from '@angular/forms'
+import { AbstractInputComponent } from '../abstract-input'
+import {
+  CdkDragDrop,
+  CdkDropList,
+  moveItemInArray,
+} from '@angular/cdk/drag-drop'
+
+@Component({
+  providers: [
+    {
+      provide: NG_VALUE_ACCESSOR,
+      useExisting: forwardRef(() => DragDropSelectComponent),
+      multi: true,
+    },
+  ],
+  selector: 'pngx-input-drag-drop-select',
+  templateUrl: './drag-drop-select.component.html',
+  styleUrl: './drag-drop-select.component.scss',
+})
+export class DragDropSelectComponent extends AbstractInputComponent<string[]> {
+  @Input() title: string = $localize`Selected items`
+
+  @Input() items: { id: string; name: string }[] = []
+  public selectedItems: { id: string; name: string }[] = []
+
+  @Input()
+  emptyText = $localize`No items selected`
+
+  @ViewChild('selectedList') selectedList: CdkDropList
+  @ViewChild('unselectedList') unselectedList: CdkDropList
+
+  get unselectedItems(): { id: string; name: string }[] {
+    return this.items.filter((i) => !this.selectedItems.includes(i))
+  }
+
+  writeValue(newValue: string[]): void {
+    super.writeValue(newValue)
+    this.selectedItems =
+      newValue?.map((id) => this.items.find((i) => i.id === id)) ?? []
+  }
+
+  public drop(event: CdkDragDrop<string[]>) {
+    if (
+      event.previousContainer === event.container &&
+      event.container === this.selectedList
+    ) {
+      moveItemInArray(
+        this.selectedItems,
+        event.previousIndex,
+        event.currentIndex
+      )
+    } else if (event.container === this.selectedList) {
+      this.selectedItems.splice(
+        event.currentIndex,
+        0,
+        this.unselectedItems[event.previousIndex]
+      )
+    } else if (
+      event.container === this.unselectedList &&
+      event.previousContainer === this.selectedList
+    ) {
+      this.selectedItems.splice(event.previousIndex, 1)
+    }
+    this.onChange(this.selectedItems.map((i) => i.id))
+  }
+}