PersistedContent: Manage Waypoints for Intents

I have an issue with the PersistedContent functionality:

I want to save a Location object as a Waypoint under the following circumstances:

Search the Apps existing Waypoints with an Iterator and compare them by name
If the name already exists: retrieve the existing waypoint and start an Intent
If the name does not exist: save a new waypoint, find it with another Iterator by name and retrieve it to start an Intent

The Problem is the second Iterator that I use is always returning null. It seems as if it is not possible to use several Iterators in the same context. Also I tried reusing the first and start the iteration from scratch in the second use case, but that does not work aswell.

Anyone experienced a similar issue with the PersistedContent iterator? And if not how are you usually handling Waypoints/Courses to start Intents for navigation?

remo over 2 years ago

Sorry, somehow the code block feature is not working in my browser, so here the code in plain text:

var waypoint = null;
var checkIterator = PersistedContent.getAppWaypoints();
var currCheckWaypoint = checkIterator.next();

// Check if Waypoint exists
while(waypoint == null && currCheckWaypoint != null) {
if(currCheckWaypoint.getName().equals(station["name"])) {
waypoint = currCheckWaypoint;
}
currCheckWaypoint = checkIterator.next();
}

// Not existing create new persisted Waypoint
if(waypoint == null) {
var location = new Position.Location( { :latitude => station["lat"], :longitude => station["lon"], :format => :degrees } );
PersistedContent.saveWaypoint(location, {:name => station["name"]});

// Retrieve Waypoint again
var iterator = PersistedContent.getAppWaypoints();
var currWaypoint = iterator.next();
while(waypoint == null) {
if(currWaypoint.getName().equals(station["name"])) {
waypoint = currWaypoint;
}
currWaypoint = iterator.next();
}
}
System.exitTo(waypoint.toIntent());

FlowState over 2 years ago

I haven't run into this problem because I don't use PersistedContent in this way, but could you use a Timer.Timer() callback as a workaround? e.g.

var waypointToOpen = null;
function createOrSaveWaypoint() {
    // ...
    PersistedContent.saveWaypoint(location, {:name => station["name"]});
  
    waypointToOpen = station["name"];
    var timer = new Timer.Timer();
    timer.start(method(:openWaypoint), 1, false);
}

function openWaypoint() {
    var iterator = PersistedContent.getAppWaypoints();
    //... (Retrieve Waypoint with name == waypointToOpen)
    System.exitTo(waypoint.toIntent());
}