Method _syncInputs

src/cdk/drag-drop/directives/drag.ts:423–485

Syncs the inputs of the CdkDrag with the options of the underlying DragRef.

(ref: DragRef<CdkDrag<T>>)

  /** Syncs the inputs of the CdkDrag with the options of the underlying DragRef. */
  private _syncInputs(ref: DragRef<CdkDrag<T>>) {
    ref.beforeStarted.subscribe(() => {
      if (!ref.isDragging()) {
        const dir = this._dir;
        const dragStartDelay = this.dragStartDelay;
        const placeholder = this._placeholderTemplate
          ? {
              template: this._placeholderTemplate.templateRef,
              context: this._placeholderTemplate.data,
              viewContainer: this._viewContainerRef,
            }
          : null;
        const preview = this._previewTemplate
          ? {
              template: this._previewTemplate.templateRef,
              context: this._previewTemplate.data,
              matchSize: this._previewTemplate.matchSize,
              viewContainer: this._viewContainerRef,
            }
          : null;

        ref.disabled = this.disabled;
        ref.lockAxis = this.lockAxis;
        ref.scale = this.scale;
        ref.dragStartDelay =
          typeof dragStartDelay === 'object' && dragStartDelay
            ? dragStartDelay
            : coerceNumberProperty(dragStartDelay);
        ref.constrainPosition = this.constrainPosition;
        ref.previewClass = this.previewClass;
        ref
          .withBoundaryElement(this._getBoundaryElement())
          .withPlaceholderTemplate(placeholder)
          .withPreviewTemplate(preview)
          .withPreviewContainer(this.previewContainer || 'global');

        if (dir) {
          ref.withDirection(dir.value);
        }
      }
    });

    // This only needs to be resolved once.
    ref.beforeStarted.pipe(take(1)).subscribe(() => {
      // If we managed to resolve a parent through DI, use it.
      if (this._parentDrag) {
        ref.withParent(this._parentDrag._dragRef);
        return;
      }

      // Otherwise fall back to resolving the parent by looking up the DOM. This can happen if
      // the item was projected into another item by something like `ngTemplateOutlet`.
      let parent = this.element.nativeElement.parentElement;
      while (parent) {
        const parentDrag = this._dragDropRegistry.getDragDirectiveForNode(parent);
        if (parentDrag) {
          ref.withParent(parentDrag._dragRef);
          break;