All files / tree-view/si-tree-view-item si-tree-view-item.directive.ts

80.43% Statements 37/46
68.75% Branches 11/16
77.77% Functions 7/9
78.04% Lines 32/41

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137                                                        1x 97x 97x 97x 97x 97x 97x   97x     97x 97x 97x 97x 2171x     97x   97x 125x         97x       222x 222x 222x         147x 147x           1161x 915x                                           246x 246x                   1161x       147x 1273x 1273x 1273x     147x                                        
/**
 * Copyright (c) Siemens 2016 - 2025
 * SPDX-License-Identifier: MIT
 */
import {
  AfterViewInit,
  ChangeDetectorRef,
  Directive,
  EmbeddedViewRef,
  inject,
  Injector,
  IterableChangeRecord,
  IterableChanges,
  IterableDiffer,
  IterableDiffers,
  OnDestroy,
  OutputRefSubscription,
  TemplateRef,
  ViewContainerRef
} from '@angular/core';
 
import { TREE_ITEM_CONTEXT } from '../si-tree-view-item-context';
import { SiTreeViewComponent } from '../si-tree-view.component';
import { TreeItem, TreeItemContext } from '../si-tree-view.model';
 
@Directive({
  selector: '[siTreeViewItem]'
})
export class SiTreeViewItemDirective implements AfterViewInit, OnDestroy {
  private templateRef = inject(TemplateRef);
  private viewContainerRef = inject(ViewContainerRef);
  private parent = inject(SiTreeViewComponent);
  private differs = inject(IterableDiffers);
  private cdRef = inject(ChangeDetectorRef);
  private differ: IterableDiffer<TreeItem> | null = null;
  private subscription!: OutputRefSubscription;
  private itemsVirtualizedDirty = true;
 
  ngAfterViewInit(): void {
    if (this.itemsVirtualizedDirty) {
      this.itemsVirtualizedDirty = false;
      const value = this.parent.itemsVirtualized;
      if (!this.differ && value) {
        this.differ = this.differs.find(value).create((_index, item) => item);
      }
    }
    this.evaluateDiffer();
 
    this.subscription = this.parent.evaluateForTreeItemsDiffer.subscribe(_ =>
      this.evaluateDiffer()
    );
  }
 
  ngOnDestroy(): void {
    this.subscription.unsubscribe();
  }
 
  private evaluateDiffer(): void {
    if (this.differ) {
      const changes = this.differ.diff(this.parent.itemsVirtualized);
      if (changes) this.applyChanges(changes);
    }
  }
 
  private applyChanges(changes: IterableChanges<TreeItem>): void {
    const viewContainer = this.viewContainerRef;
    changes.forEachOperation(
      (
        record: IterableChangeRecord<TreeItem>,
        adjustedPreviousIndex: number | null,
        currentIndex: number | null
      ) => {
        if (record.previousIndex == null) {
          viewContainer.createEmbeddedView(
            this.templateRef,
            {
              treeItem: record.item,
              index: record.currentIndex,
              parent: this.parent
            },
            {
              injector: Injector.create({
                providers: [
                  {
                    provide: TREE_ITEM_CONTEXT,
                    useValue: {
                      record,
                      parent: this.parent
                    }
                  }
                ]
              }),
              index: currentIndex ?? undefined
            }
          );
        } else if (currentIndex == null) {
          viewContainer.remove(adjustedPreviousIndex ?? undefined);
        } else IEif (adjustedPreviousIndex !== null) {
          const view = viewContainer.get(adjustedPreviousIndex)!;
          viewContainer.move(view, currentIndex);
          (view as EmbeddedViewRef<TreeItemContext>).context = {
            treeItem: record.item,
            index: record.currentIndex!,
            parent: this.parent
          };
        }
        this.cdRef.detectChanges();
      }
    );
 
    for (let i = 0, ilen = viewContainer.length; i < ilen; i++) {
      const viewRef = viewContainer.get(i) as EmbeddedViewRef<TreeItemContext>;
      const context = viewRef.context;
      context.index = i;
    }
 
    changes.forEachIdentityChange((record: IterableChangeRecord<TreeItem>) => {
      Iif (record.currentIndex) {
        const viewRef = viewContainer.get(record.currentIndex) as EmbeddedViewRef<TreeItemContext>;
        viewRef.context = {
          treeItem: record.item,
          index: record.currentIndex,
          parent: this.parent
        };
        this.cdRef.detectChanges();
      }
    });
  }
 
  static ngTemplateContextGuard(
    _dir: SiTreeViewItemDirective,
    ctx: unknown
  ): ctx is TreeItemContext {
    return true;
  }
}