createNode

create_router_state.ts

function createNode(
    routeReuseStrategy: RouteReuseStrategy, curr: TreeNode<ActivatedRouteSnapshot>,
    prevState?: TreeNode<ActivatedRoute>): TreeNode<ActivatedRoute> {
  // reuse an activated route that is currently displayed on the screen
  if (prevState && routeReuseStrategy.shouldReuseRoute(curr.value, prevState.value.snapshot)) {
    const value = prevState.value;
    value._futureSnapshot = curr.value;
    const children = createOrReuseChildren(routeReuseStrategy, curr, prevState);
    return new TreeNode<ActivatedRoute>(value, children);

    // retrieve an activated route that is used to be displayed, but is not currently displayed
  } else {
    const detachedRouteHandle =
        <DetachedRouteHandleInternal>routeReuseStrategy.retrieve(curr.value);
    if (detachedRouteHandle) {
      const tree: TreeNode<ActivatedRoute> = detachedRouteHandle.route;
      setFutureSnapshotsOfActivatedRoutes(curr, tree);
      return tree;

    } else {
      const value = createActivatedRoute(curr.value);
      const children = curr.children.map(c => createNode(routeReuseStrategy, c));
      return new TreeNode<ActivatedRoute>(value, children);
    }
  }
}