Say I add a Control.Layers object on a map like this:
L.control.layers(baseLayers, overlays).addTo(someMap)
When I am later given the someMap object what is the proper way to obtain the layer control from it? E.g. I was hoping something like:
let controls = someMap.getControls();
... where I would then presumably be able to iterate and use the typeof operator to find the control I am interested in.
The closest I have found in answering the question is this SO answer which suggests extending the L.Control class and overriding onAdd in order to store a custom property on the map object. I find it hard to be believe it needs to be so convoluted as that. Plus, even if that approach was taken, how I am supposed to know that my overridden onAdd method does everything that the implementation in the original Layers Control.Layers does?
The way it is implemented, adding a control to a map just leaves the control object with reference to the map object.
This means that the map object is unaware of the controls it has created (EDIT I should say: controls that were added to the map)
I guess there was no need for that. If you have a use case that shows this is a problem, you should open an issue.
So, I'm afraid the answer you already have is the right one.
Related
I will need to create a Custom Button "convert lead" that will perform the same functionality as Standard Button "Convert" when the button is clicked.
What is the best approach to do it..?
That's a very broad question. What exactly you need, what have you tried so far? Do you really need just a button that opens the conversion page or something more?
If you want to somehow recreate it with Apex... Core of the coded solution would be the Database.convertLead method. You don't pass to it whole leads (like to Database.insert for example) but instead just their IDs + bunch of control flags to make it do exactly what you need. Read up about LeadConvert object. And similarly you can get Account/Contact/Opportunity ID from the result object if it succeeded.
I don't think there's programmatic way to access field names & mappings defined by administrator for lead conversion. Maybe you'd need to store this info somehow (in helper object? custom metadata?). So then you'd query the field names from metadata, then query the lead fields and finally display table of fields & mappings to the user.
I'm writing MapBox vector tiles using geotrellis vectorpipe.
see here for the basic flow: https://geotrellis.github.io/vectorpipe/usage.html
Typically GeoJson Features can have an id field, so that Features can be rolled up into FeatureCollections. I need to make use of this field, but vectorpipe doesn't (natively) have this capability.
This is the Feature type used, and you can see it only has space for 1) a Geometry and 2) a data object D (which ends up populating properties in the output). There is no spot for an id.
https://geotrellis.github.io/scaladocs/latest/index.html#geotrellis.vector.Feature
Upstream there's a method called writeFeatureJsonWithID() that does let you inject an id field into a Feature when writing GeoJson.
https://github.com/locationtech/geotrellis/blob/master/vector/src/main/scala/geotrellis/vector/io/json/FeatureFormats.scala#L41-L49
My question is this:
I have worked through the vectorpipe code (https://github.com/geotrellis/vectorpipe), and I can't figure out if/where the data ever exists as GeoJson in a way where I can override and inject the id, maybe using the writeFeatureJsonWithID() or something I write explicitly. A lot of conversions are implicit, but it also may never explicitly sit as json.
Any ideas for how to get an id field in the final GeoJson written to vector tiles?
EDIT
Right now I think the trick is going to be finding a way to override .unfeature() method here:
https://github.com/locationtech/geotrellis/blob/master/vectortile/src/main/scala/geotrellis/vectortile/Layer.scala
The problem is that the internal.vector_tile.Tile is private, so I can construct it without forking the project.
Ended up having to fork geotrellis, hard-code a metadata => id function in Layer.unfeature() and compile locally to include in my project. Not ideal, but it works fine.
Also opened an issue here: https://github.com/locationtech/geotrellis/issues/2884
With intellij idea, how do I find out what makes a variable be visible?
An example of when it is hard:
Suppose you look at class A, and you see a variable something. If you jump to source you see that it's defined in trait X. But you don't extend trait X directly. What do you extend, then, that makes this variable visible? If you have a deeply nested hierarchy, tracking can be hard.
Any recommendations or solutions?
EDIT: Please vote for the feature if you're interested: http://youtrack.jetbrains.com/issue/IDEA-124369
I don't think that IntelliJ IDEA has any shortcut for "finding what makes a variable visible".
However you can determine it using the "Find Usages" option (Alt + F7). For example:
import java.nio._
object TempObj extends App {
def func = 2
val p = file.Paths.get("some-path")
func
}
So Find Usages on "file", tells you that its from the Package "file" (in heading of the new Tab it also shows the complete package name, ex: Find Usages of java.nio.file in Project Files).
Whereas Find Usages on func will tell you that its a Method (And the Tab heading now says: Find Usages of func() in Project and Libraries)
So now in way you can determine, what exactly makes the variable visible. This also works for imports since it shows the package from which it is imported and you can then look for import of that packages.
I know of two almost-solutions to this problem.
Go-to-declaration, as you mentioned, solves this problem in the case of local variables.
More generally, the "find usages" feature gives you a neat little breakdown by type and file of different uses of the variable. From this you can see if it's involved in a static import.
It's not perfect, but with a moment's thought these two are generally sufficient to figure out what you want.
Use ctrl+b or F4 to jump to source code. Alternatively you can use ctrl+shift+a to get option/action. You can find shortcuts at http://gaerfield.github.io/ide-shortcuts/ as well. Hope it will help.
From what I understood you want to see the code that creates an Object you use, for instance Mystery someMystery;.
That gives you two options to populate someMystery:
someMystery = ... where ... is your code to populate
someMystery and if that is the case you should follow
that code (with ctrl+B as far as you need to) to the point where it
actually creates the Mystery object.
Use CDI to populate that object instance for you, in which case you should look into the CDI mechanism in order to see in what way the object instance is populated.
In either way IMO there is no way to know for sure if the someMystery instance is of some more concrete class than Mystery, because it is decided in runtime, not in compile time, so your next bet would be to run the program in debug and see what object goes into someMystery, although you are not guaranteed to get the same type of object every time.
PS. My answer is based entirely on my java understanding of the topic, can't say if it is valid for scala also.
This might not be exactly the answer you were hoping to get.
However, quoting yourself,
If you have a deeply nested hierarchy, tracking can be hard.
Have you considered using composition over inheritance? Perhaps this would remove the need for the feature you are looking for.
Deeply nested hierarchy doesn't sound good. I understand your pain about that.
When you override vals or defs there is a little circle next to the line number that shows where it is from even when it is from nested hierarchy. Hovering over vals with the command key down also shows you a little tooltip where it is from.
Does this help?
https://youtu.be/r3D9axSlBo8
if you want class, field or method to be visible, you need to implement them as public. If it was your question.
I am making a graphically simple 3D game in C++ using DirectX. The main problem I am having is with how to structure some things efficiently. Right now I know my goal for certain areas but not how to ideally perform them.
For instance, right now I am storing all meshes and textures in an Asset class with enumerated definitions pointing to each asset. All meshes and textures are loaded when the game starts by creating an Asset object and initializing it. From there I load meshes and textures to objects by assigning the pointer given by the Asset object. Is this the best way to go about this?
A harder topic is that of items. For the sake of argument I am going to say we are dealing with scenery. Right now my scenery needs the following:
A name
A mesh
Textures (optional)
Flags (such as Destructible, Flammable, etc.)
Status (such as Burning, Locked, Cursed, etc.)
Abilities (things the object actually does, such as becoming damaged when burning)
The first 5 things on this list are simply variables. But abilities are bothering me. The first 5 can all exist in one item class. But what I do not know how to do is somehow attach abilities to the object.
For example; I want the object to have the "Fire Nova" ability. At the start of each turn, the object damages anything near it.
For me, this means each object would need a "Trigger_Phase_TurnStart()" or some similarly named method and would then need a new "Fire Nova" class with its own unique action for that trigger and its own extra variables (Damage, Range, etc). So now I have the base object class and a new Fire Nova class that inherits from it.
But now what if I needed an object that has Fire Nova and Frost Nova and also Slowing Aura and other such abilities. Basically I need a way to add triggered effects to an object without needing a new object class for each of them.
So by the end I would be able to have say:
(pseudo code of the object's components)
name = Elemental Orb
mesh = "Mesh_Sphere"
textures[] = "Tex_Ice", "Tex_Fire"
flags = OF_Destructible
status = SF_Cursed | SF_Burning
abilities[] = Fire_Nova, Frost_Nova, Slowing_Aura
And this orb would simply be the object class with all these attributes. The object would then activate each stored ability's trigger at the appropriate turn phase for any actions to perform.
Right now I am thinking I might need to make a class for each ability possessing every turn-phase or action trigger (inherited from a base ability class) and have them perform the appropriate action when the object calls them from it's array of abilities. Would this be the best way to do this?
As a separate issue. Some flags would require additional variables that would otherwise be unnecessary. For example, Destructible would mean the object would have health whereas without the flag it wouldn't need it, or an Openable item would need an array of contents. What would be a good way to ration these variables to when they are needed? I do not need every wall to have health and an empty contents array for example.
Finally. Assuming the bullet-listed attributes above are all an item needs, how might you suggest I best store them? To clarify, I would like to be able to write:
CreateItem(ITEM_CHAIR);
and have this return the created object with name, mesh, textures, flags, status and abilities. What structure might be suitable for achieving such an end effect?
To summarise:
Does my current Asset storage seem feasible?
What is the best way to create abilities to attach to the object class without making numerous separate object classes?
Is there a way to limit the variables (or at least memory usage) when the associated flag is not present?
What structure or format would be best for storing fixed item definitions?
Sorry if this is a little long winded. If you cannot answer all the questions then an answer to one would still be appreciated. Question two is probably the largest priority for me right now.
Thanks for your time :)
I want only answer question 2 and it looks like you need a decorator pattern. In OOP a decorator pattern is useful when you have many ingredients and wants to decorate an object, for example a pizza. Unfortunately you need to create for each ingredient a separate class hence I think you have the right approach. The good thing is that with the decorator pattern you can wrap the object over and over with abilites classes and call only one method at the end to do all the stuff.
I would like to know if there is a function that when i give it an ASTNode object (the ASTNode can be a class, method or a field in a CompilationUnit) as an argument it can show this object in a view (Tree view or Table view). If there isn't any such function, is there another way or workaround of doing it?
Thanks for your help.
You may be able to use the ASTView plugin
It's not clear if you are referring to Java or just something else. I'm assuming you need a Java tool. I'm not sure what exactly you expect to see in the "view".
Do check out nWire. It may be what you are looking for. Given any component in your code (like Class, field, etc.) it can show all possible associations to other components.