ng2-bootstrap-base-modified/src/sortable/sortable.component.ts

Native Angular Bootstrap Components Typeahead modified

import {
  Component, Input, Output, EventEmitter, forwardRef, TemplateRef
} from '@angular/core';
import { NG_VALUE_ACCESSOR, ControlValueAccessor } from '@angular/forms';
import { DraggableItem } from './draggable-item';
import { DraggableItemService } from './draggable-item.service';

/* tslint:disable */
@Component({
  selector: 'bs-sortable',
  exportAs: 'bs-sortable',
  template: `
<div
    [ngClass]="wrapperClass"
    [ngStyle]="wrapperStyle"
    [ngStyle]="wrapperStyle"
    (dragover)="cancelEvent($event)"
    (dragenter)="cancelEvent($event)"
    (drop)="resetActiveItem($event)"
    (mouseleave)="resetActiveItem($event)">
  <div
        *ngIf="showPlaceholder"
        [ngClass]="placeholderClass"
        [ngStyle]="placeholderStyle"
        (dragover)="onItemDragover($event, 0)"
        (dragenter)="cancelEvent($event)"
    >{{placeholderItem}}</div>
    <div
        *ngFor="let item of items; let i=index;"
        [ngClass]="[ itemClass, i === activeItem ? itemActiveClass : '' ]"
        [ngStyle]="getItemStyle(i === activeItem)"
        draggable="true"
        (dragstart)="onItemDragstart($event, item, i)"
        (dragend)="resetActiveItem($event)"
        (dragover)="onItemDragover($event, i)"
        (dragenter)="cancelEvent($event)"
    ><template [ngTemplateOutlet]="itemTemplate || defItemTemplate"
  [ngOutletContext]="{item:item, index: i}"></template></div>
</div>

<template #defItemTemplate let-item="item">{{item.value}}</template>  
`,
  providers: [{
    provide: NG_VALUE_ACCESSOR,
    useExisting: forwardRef(() => SortableComponent),
    multi: true
  }],
})
/* tslint:enable */
export class SortableComponent implements ControlValueAccessor {
  private static globalZoneIndex: number = 0;

  /** field name if input array consists of objects */
  @Input() public fieldName: string;

  /** class name for items wrapper */
  @Input() public wrapperClass: string = '';

  /** style object for items wrapper */
  @Input() public wrapperStyle: {[key: string]: string} = {};

  /** class name for item */
  @Input() public itemClass: string = '';

  /** style object for item */
  @Input() public itemStyle: {[key: string]: string} = {};

  /** class name for active item */
  @Input() public itemActiveClass: string = '';

  /** style object for active item */
  @Input() public itemActiveStyle: {[key: string]: string} = {};

  /** class name for placeholder */
  @Input() public placeholderClass: string = '';

  /** style object for placeholder */
  @Input() public placeholderStyle: {[key: string]: string} = {};

  /** placeholder item which will be shown if collection is empty */
  @Input() public placeholderItem: string = '';

  /** used to specify a custom item template. Template variables: item and index; */
  @Input() public itemTemplate: TemplateRef<any>;

  /** fired on array change (reordering, insert, remove), same as <code>ngModelChange</code>.
   *  Returns new items collection as a payload.
   */
  @Output() public onChange: EventEmitter<any[]> = new EventEmitter<any[]>();

  public showPlaceholder: boolean = false;
  public activeItem: number = -1;

  public get items(): SortableItem[] {
    return this._items;
  }

  public set items(value: SortableItem[]) {
    this._items = value;
    let out = this.items.map((x: SortableItem) => x.initData);
    this.onChanged(out);
    this.onChange.emit(out);
  }

  public onTouched: any = Function.prototype;
  public onChanged: any = Function.prototype;

  private transfer: DraggableItemService;
  private currentZoneIndex: number;
  private _items: SortableItem[];

  public constructor(transfer: DraggableItemService) {
    this.transfer = transfer;
    this.currentZoneIndex = SortableComponent.globalZoneIndex++;
    this.transfer.onCaptureItem()
      .subscribe((item: DraggableItem) => this.onDrop(item));
  }

  public onItemDragstart(event: DragEvent, item: SortableItem, i: number): void {
    this.initDragstartEvent(event);
    this.onTouched();
    this.transfer.dragStart({
      event,
      item,
      i,
      initialIndex: i,
      lastZoneIndex: this.currentZoneIndex,
      overZoneIndex: this.currentZoneIndex
    });
  }

  public onItemDragover(event: DragEvent, i: number): void {
    if (!this.transfer.getItem()) {
      return;
    }
    event.preventDefault();
    let dragItem = this.transfer.captureItem(this.currentZoneIndex, this.items.length);
    let newArray: any[] = [];
    if (!this.items.length) {
      newArray = [dragItem.item];
    } else if (dragItem.i > i) {
      newArray = [
        ...this.items.slice(0, i),
        dragItem.item,
        ...this.items.slice(i, dragItem.i),
        ...this.items.slice(dragItem.i + 1)
      ];
    } else { // this.draggedItem.i < i
      newArray = [
        ...this.items.slice(0, dragItem.i),
        ...this.items.slice(dragItem.i + 1, i + 1),
        dragItem.item,
        ...this.items.slice(i + 1)
      ];
    }
    this.items = newArray;
    dragItem.i = i;
    this.activeItem = i;
    this.updatePlaceholderState();
  }

  public cancelEvent(event: DragEvent): void {
    if (!this.transfer.getItem() || !event) {
      return;
    }
    event.preventDefault();
  }

  public onDrop(item: DraggableItem): void {
    if (item &&
      item.overZoneIndex !== this.currentZoneIndex &&
      item.lastZoneIndex === this.currentZoneIndex
    ) {
      this.items = this.items.filter((x: SortableItem, i: number) => i !== item.i);
      this.updatePlaceholderState();
    }
    this.resetActiveItem(undefined);
  }

  public resetActiveItem(event: DragEvent): void {
    this.cancelEvent(event);
    this.activeItem = -1;
  }

  public registerOnChange(callback: (_: any) => void): void {
    this.onChanged = callback;
  }

  public registerOnTouched(callback: () => void): void {
    this.onTouched = callback;
  }

  public writeValue(value: any[]): void {
    if (value) {
      this.items = value.map((x: any, i: number) => ({
        id: i,
        initData: x,
        value: this.fieldName ? x[this.fieldName] : x
      }));
    } else {
      this.items = [];
    }
    this.updatePlaceholderState();
  }

  public updatePlaceholderState(): void {
    this.showPlaceholder = !this._items.length;
  }

  public getItemStyle(isActive: boolean): {} {
    return isActive
      ? Object.assign({}, this.itemStyle, this.itemActiveStyle)
      : this.itemStyle;
  }

  private initDragstartEvent(event: DragEvent): void {
    // it is necessary for mozilla
    // data type should be 'Text' instead of 'text/plain' to keep compatibility
    // with IE
    event.dataTransfer.setData('Text', 'placeholder');
  }
}

export declare interface SortableItem {
  id: number;
  value: string;
  initData: any;
}