clr-angular-static-fix/data/datagrid/providers/hideable-column.service.ts

1. Install Clarity Icons package through npm:

/*
 * Copyright (c) 2016-2018 VMware, Inc. All Rights Reserved.
 * This software is released under MIT license.
 * The full license information can be found in LICENSE in the root directory of this project.
 */

import { Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs';
import { Observable } from 'rxjs';

import { DatagridHideableColumnModel } from '../datagrid-hideable-column.model';

/**
 *
 * @description
 * An @Injectable provider class that enables
 *
 * 1. Managing, track hideability of DatagridColumns
 *
 */
@Injectable()
export class HideableColumnService {
  /**********
   * @property dgHiddenColumnMap
   *
   * @description
   * An array of DatagridHideableColumn.
   * NOTE: because we can have columns w/o the *clrDgHideableColumn directive
   * this array will have empty spaces a.k.a nulls. This is needed to be able to map
   * DatagridCells to DatagridColumns in the RowRenderer.
   *
   */
  private _columnList: DatagridHideableColumnModel[] = [];

  /**********
   *
   * @property dgHiddenColumnMapChange
   *
   * @description
   * A behavior subject that can broadcast updates to the column list.
   * NOTE: I am using BehaviorSubject because <clr-dg-column-toggle> is not getting the latest _columnListChange
   * on page load.
   *
   */
  private _columnListChange: BehaviorSubject<DatagridHideableColumnModel[]> = new BehaviorSubject<
    DatagridHideableColumnModel[]
  >(this._columnList);

  /**********
   *
   * @property canHideNextColumn
   *
   * @description
   * Service function that is called by clr-dg-column-toggle component. Use this if you need to ask if you can hide
   * a column. It acts as a guard against hiding all the columns making sure there is at least one column displayed.
   *
   */
  public get canHideNextColumn(): boolean {
    const hiddenColumns = this._columnList.filter(column => column !== undefined).filter(column => column.hidden);
    return this._columnList.length - hiddenColumns.length > 1;
  }

  /**********
   *
   * @property checkForAllColumnsVisible
   *
   * @description
   * For when you need to know if the datagrid's columns are all showing.
   *
   */
  public get checkForAllColumnsVisible(): boolean {
    return !this._columnList.some(column => column && column.hidden);
  }

  /***********
   * @property columnListChange
   *
   * @description
   * A public property that enables subscribers to hear updates to the column map.
   * Use this if you need to do something whenever the Datagrid's column list is changed (i.e *ngIf on a column).
   *
   */
  public get columnListChange(): Observable<DatagridHideableColumnModel[]> {
    return this._columnListChange.asObservable();
  }

  /**********
   *
   * @description
   * Public function that returns the current list of columns. I needed an array of to iterate on in the RowRenderer
   * but subscribing to the _columnListChange changes did not seem like the correct way to get it.
   *
   */
  public getColumns(): DatagridHideableColumnModel[] {
    return this._columnList;
  }

  /**********
   *
   * @description
   * Iterate through the current _columnList:
   * - if it has a DatagridHideableColumn and is hidden then show it.
   * - if it's DatagridHideableColumn was previously the last column visible, turn that flag off.
   *
   */
  public showHiddenColumns() {
    this._columnList.forEach(column => {
      if (column && column.hidden === true) {
        column.hidden = false;
      }

      if (column && column.lastVisibleColumn) {
        column.lastVisibleColumn = false;
      }
    });
  }

  /**
   *
   * @param columns: DatagridColumn[]
   *
   * @description
   * Creates an array of DatagridHideableColumn's || null based column array passed as param.
   * Is dependent on the order in @ContentChildren in Datagrid.
   *
   */
  public updateColumnList(columns: DatagridHideableColumnModel[]) {
    this._columnList = columns; // clear the list
    this.updateForLastVisibleColumn(); // Update our visibility state for UI
    this._columnListChange.next(this._columnList); // Broadcast it
  }

  /**********
   *
   * @description
   * Gets the current visible count for all columns.
   * When it is greater than 1 it marks everything as false for the lastVisibleColumn.
   * When visible count is not > 1 (i.e) 1. , it finds the only column that is not hidden and marks it as the
   * lastVisibleColumn.
   *
   */
  public updateForLastVisibleColumn(): void {
    // There is more than one column showing, make sure nothing is marked lastVisibleColumn
    if (this.canHideNextColumn) {
      this._columnList.map(column => {
        if (column && column.lastVisibleColumn) {
          column.lastVisibleColumn = false;
        }
      });
    } else {
      // The visibleCount is down to only one column showing. Find it and flag it as the lastVisibleColumn
      this._columnList.map(column => {
        if (column && !column.hidden) {
          column.lastVisibleColumn = true;
        }
      });
    }
  }

  /**********
   *
   * @description
   * Return a HideableColumn in this._columnList for the given id.
   *
   *
   */
  public getColumnById(id: string): undefined | DatagridHideableColumnModel {
    if (id) {
      return this._columnList.find(column => column && column.id === id);
    }
    return;
  }
}