I'm using JS api. I need to recalculate route if waypoint is changed (via input field or waypoint marker is dragged).
As i understand, we can't recalculate existing route, so we need to destroy the previous one and to make the new one?
So how should i destroy the existing one as i have only "routes" object available inside the addWaypointsToMap function?
Well, i resolved it.
The moment route is changed (waypoint dragged or relocated) i check if map groups for polygon and waypoints markers exist and kill'em, then make new route.
Not sure what does exactly "recalculate existing route" means, but if it means to update Polyline map object based on new routing response then you can simply use
H.map.Polyline#setGeometry()
The method is documented here: https://developer.here.com/documentation/maps/3.1.16.1/api_reference/H.map.Polyline.html#setGeometry
Here is a simple jsfiddle example to set start & destination (as well as middle waypoint) point by mouse right-click and re-calculate the route.
Related
I have an app using React + Redux and coupled with Firebase for the backend.
Often times, I will want to add some new attributes to existing objects.
When doing so, existing objects won't get the attribute until they're modified with the new version of the app that handles those new attributes.
For example, let's say I have a /categories/ node, in there I've got objects such as this :
{
name: "Medical"
}
Now let's say I want to add an icon field with a default of "
Is it possible to update all categories at once so that field always exists with the default value?
Or do you handle this in the client code?
Right now I'm always testing the values to see if they're here or not, but it doesn't seem like a very good way to go about it. I'd like to have one place to define defaults.
It seems like having classes for each object type would be interesting but I'm not sure how to go about this in Redux.
Do you just use the reducer to turn all categories into class instances when you fetch them for example? I'm worried this would be heavy performance wise.
Any write operation to the Firebase Database requires that you know the exact path to the node that you're writing.
There is no built-in operation to bulk update nodes with a path that is only partially known.
You can either keep your client-side code robust enough to handle the missing properties, or you can indeed run a migration script to add the new property to each relevant node. But since that script will have to know the exact path of each node to write, it will likely first have to read/query the database to determine those paths. Depending on the number of items to update, it could possibly use multi-location updates after that to update multiple nodes in one call. E.g.
firebase.database().ref("categories").update({
"idOfMedicalCategory/icon": "newIconForMedical",
"idOfCommercialCategory/icon": "newIconForCommercial"
"idOfTechCategory/icon": "newIconForTech"
})
Normally, I create my BizTalk mappings in the XSL. Today I was playing around with the mapper but I am failing to do the most basic thing and googling it fails me (I find unrelated questions or the basic way to do it in XSL)
The question is simple though, I want to use the BizTalk mapper (btm file) to map one element to another and fill a second element with a fixed value.
Looking at the functoids, I have a date functoid which gets today's date but nothing to just type some text and map it.
Am I missing something very obvious?
The "built in" way to do this is to set the Value property on the destination node in the map (you can also use this property to desginate that an empty node should be created for this destination node). Unfortunately, this method offers no visual representation that the node is being set this way, except that it will prevent you from linking other nodes/functoids to that destination node. This may lead future devs (or your future self) to think the node isn't being set, or be confused as to why it's being set when it has no inputs.
To get around this, I've frequently used either a String Concatenate functoid (with the fixed value as the only parameter, manually typed in) or a Value Mapping functoid (set "true" as the first parameter and the fixed value as the second parameter). This offers a few benefits:
Visually shows that node is being set by the map
Allows you to set a meaningful label and/or comment on the functoid to denote why you're setting that value.
TL;DR
Is PinView.prototype = _.extend(PinView.prototype, google.maps.OverlayView.prototype) the "proper" way to have a Backbone View inherit from another "class"?
Long read
We're redoing our site using Backbone and are working on including some mapping functionality.
I've got a Backbone view that handles placing <div>s onto specific points within the browser window; this seems like a natural thing to extend in order have Google's Map API place them on geographical coordinates.
According to the Google API, in order to generate a custom overlay you create a new object and set the prototype for that object to a new instance of google.maps.OverlayView. You then implement three functions on top of that object so that the object responds to:
onAdd
draw
onRemove
Where onAdd is responsible for generating the HTML and then applying it on top of the Map. This subsequently calls draw which positions the element correctly according to the LatLng pairs and bounds you've provided. onRemove gets called when you want to get rid of your layer.
So I've modified my View to include these three methods (which just call render and unrender and are bound to my collection). And then to make "the magic happen" I'm doing:
PinView.prototype = _.extend(PinView.prototype, google.maps.OverlayView.prototype)
Does this look right? I can post the code for the View and the Model on which it's based, but honestly, they're irrelevant to this example -- the code works and I'm able to place custom divs generated through Backbone model, view and controller components on the map without a issue, what I'm asking I guess (and maybe this question is more apropos for programmers.se, so let me know and I'll move it).
This seems to be the easiest way to make my PinView both a Backbone View and a Google Maps OverlayView, but I'm not 100% comfortable with prototypal inheritance to know if I'm doing something "wrong" or breaking something somewhere down the road.
Nice idea! I'm usually a bit sceptical about weather or not you're 'correct' when things work so if you haven't run into a showstopper and the overlays shows up and does what the're supposed to do I'd say you are.
One thing to check out closer, though:
This isn't (and can't) be "real" multiple inheritance - that concept isn't really relevant in a prototype based language: one implementation of a method will inevitable "win" and overwrite the other implementation, at least when using _.extend()
This means that if there are members or methods with the same names in Backbone.View and google.maps.OverlayView the one last in your _.extend() call will be the one that takes over. But when I inspect them using Chrome's Developer Tools I didn't see any obvious collision of this kind.
So my recommendation: continue using this, just test a lot. I'd love to see an example of this technique some time.
Ah! So I've been doing the above, but it's never felt right.
Then I found this discussion on a Backbone group which leads me to the following:
var MyView = (function(){
var view = function(){
Backbone.View.apply(this, arguments);
};
view.extend = Backbone.View.extend;
_.extend(view.prototype, Backbone.View.prototype, google.maps.OverlayView.prototype, [other prototypes...], { [VIEW DEFINITION] });
return view;
}());
This way if we need to override any of the definitions in a class we're extending from, we can since it's earlier in the _.extend chain (later definitions overwrite earlier definitions).
I'm working on 'extending' extend to keep track of the "parent" object's references that would be overridden and providing a method to call them still (like Python's super call). I haven't decided if this should be done through monkey-patching, an intercepter pattern (via underscore's _.tap() method or something else, but I think it'll add a lot of flexibility.
This would allow you to define an initialize view in your "parent" class which could be called by doing something like _.super('ParentClass', 'initialize'); at the end of the "child" class's initialize routine...
I have to change the data set displayed on a map according to selections on the page and I would like to do this by creating several marker layers then switching between them based on user input.
For some reason I cannot add a layer after the map has been rendered on the page, seems like it shouldn't be that hard I think I may have the syntax wrong since the way Drupal sets up the map is different from straight forward openlayers.
Can I not get the map object like
var map = Drupal.settings.openlayers.maps["openlayers-map-auto-id-0"];
then add and remove marker layers from it? maybe there's another way of getting it?
Any help appreciated,
- Chris
The Drupal OpenLayers module only stores settings in Drupal.settings.openlayers.maps.
What you need is something like this:
var ol = $('#openlayers-map-auto-id-0').data('openlayers');
var max_extent = ol.openlayers.getMaxExtent(); // Or some other OpenLayers method...
...
The actual OpenLayers instance (as well as a copy of the map-specific settings) are stored with jQuery's .data() method. When you call $('#map-id').data('openlayers') you'll get back an object with map and openlayers members that correspond to the map settings and the actual OL object instance, respectively.
You might want to consider writing an OL behavior to handle your use case -- check out the default behaviors provided by the Drupal OpenLayers module to get a sense of how this works.
I'm currently building the client side of a Flex/PHP project using the Presentation Model pattern.
What I'm trying to achieve:
I currently have a view displaying non-editable information about a domain object called Node. Depending on if the Node is editable and the user has the right privileges, an additional view becomes available where it's possible to make changes to this object. Any changes made are only committed to the server once the user decides to "Save Changes". If changes are made to a NodeA and the user navigates away to a different NodeB without saving them, NodeA is reverted to its original state.
Design:
I have a PM for the info view holding a reference to the current Node. The PM for the edit view is extended from this info PM, adding methods to make changes to the wrapped Node object. Both PMs has the same Node reference injected into them and all fields in the info/edit views are bound to the Node via their PMs.
The problem:
When the user makes changes to NodeA but doesn't commit them, I can't seem to think of an elegant solution to revert back to the original state. Basically, what I've thought of so far is to hold separate value copies on the edit PM, either clone-creating a new Node reference or through an identical set of Node properties. Of these two the former seems like the better idea because the Node already houses domain logic, but I wonder whether creating clones of unique domain objects is a bad practice, even if it's used in a limited scope.
I handle similar cases by storing the original data in an XML property of the Value Object ("VO"), and reset all of the other property values when the VO is needed.
So, when it is first needed to be viewed, I go get the XML:
<Node>
<prop1>value</prop1>
<prop2>value</prop2>
<prop3>value</prop3>
<prop4>value</prop4>
</Node>
When I retrieve the XML, in my result handler, the first thing I do is create an instance of my VO, and set the XML property, and then call a public function in a separate class to set the VO's properties:
private function getNodeResultHandler(event:ResultEvent):void
{
var myNode:Node = new Node();
myNode.xmlData = new XML(event.result);
nodeUtils.setNodeProperties(myNode);
}
public class nodeUtils
{
public function setNodeProperties(node:Node):void
{
var nodeXmlData:XML = node.xmlData;
myNode.prop1 = nodeXmlData.prop1;
myNode.prop2 = nodeXmlData.prop2;
myNode.prop3 = nodeXmlData.prop3;
myNode.prop4 = nodeXmlData.prop4;
}
}
Then, any time you switch your view to edit mode, you call that same function to reset the properties to the values stored in the XML.
The only other thing you need to do is reset that XML any time the user commits changes to the VO. I usually handle this by passing back the VO's data in the same format on a Save and Get, and then saving the XML just as above.
I usually do this in a Cairngorm MVC application, so I have event/command chains to handle all of this, but you can put this functionality in any number of classes, or in the VO class itself, whichever is easiest for you to maintain.
Each view should have it's own instance of your Presentation Model class. Just maintain it in memory if the user has not saved it when moving to another view. Cloning accomplishes basically the same thing through a more convoluted process.