Say you have created an instance of some GameComponent subclass and used Game.Components.Add(component) so that its Initialize and Update functions will be called by the framework. Now if component goes out of scope and has no existing references besides the Game.Components list, will it continue to be updated until I call Game.Component.Remove(component), or is it removed automatically?
In other words, when is the proper time and what is the proper way to remove a component from Game.Components?
Related
I would like one instance of a model in memory to serve as a template for creating other objects for performance reasons, so that duplicates look like the original object but otherwise share no common components with the object they are initialized from, as if they were loaded with Model.find(template_object.id). I've tried some of the available solutions but none seems to do what I need: .dup and .deep_dup will create a new object with nil id and .clone will make some of the fields common to both the initializer and the initialized.
Currently my API is giving out the original objects that I keep as class variables, but I discovered that it leads to obscure memory leaks when the code using the objects manipulates their associations - these are kept in memory indefinitely. I hope that by giving out copies the associations of the template objects will stay untouched and the leak will be gone.
This sounds like the use case for defining a class and just initializing instances. You can customize whatever properties you want shared in the MyClass#new method. Without knowing more about your needs I will add that if you must store a template in memory you could store it as a class variable perhaps MyClass##template but would need to hear more to opine further. 😄
What I found when browsing rails source is the .instantiate method:
MyModel.instantiate(#my_other_instance.attributes_before_type_cast.deep_dup)
I am using Lua to extend my C++ application. My application have some parts(ex: timer event, ui events) that can be extended by Lua, so for each part, I make a new state and load files and functions related to that part in it, so making a change to a part and reloading it wont affect the other parts.
Now I am in a situation that I need some general files to be shared among all other parts.
like for example : I am making a function for the timer events part, and there is a object defined in those general files i want to change its info in this function.
Now i am in the ui event part and I need when i access that object in the general file I want it to contain the changes that was made from the ui part.
So I thought about creating another state for those and like make an __index for the global table in the other state to search this state if they don't find some stuff in it:)) apparently I don't know how to make that.
I hope someone get what I mean and tell me how to make that?!
Lua states created with lua_newstate or lua_newstate are completely separated and cannot directly talk to each other: you need to copy data manually from one state to the other.
You can set an __index metamethod for the global table in one state to look for the data in the other one, but you'll have to do it in C or export a function to Lua that does that.
Suppose I register some instance in OpenRasta's dependency resolver using
resolver.AddDependencyInstance(IInterface, instance, DependencyLifetime.Singleton)
Now if I want to swap that instance later, say to reread fresh data from the db, is another call to resolver.AddDependencyInstance the right thing to do?
Checking the InternalDependencyResolver implementation, it seems to be fine. However I'm asking because the behavior is not defined (in openrasta's sources, where I checked), and the method prefix "Add" is suggestive of different behavior.
I wouldn't use Singleton if you have to swap the instance at some point.
Use DependencyLifetime.Transient and have a constructor injection in the class where you need the new instance
I am putting together a built-in script capability using the excellent Pascal DWScript. I have also add my own Delphi-side class definition (TDemo) to DWScript using:
dwsUnit.ExposeRTTI( TDemo.ClassInfo )
This just works and is a great way of quickly adding properties and methods.
I also wish to add an existing instance in a similar way, so I have created my instance FDemo of type TDemo and then performed:
dwsUnit.ExposeInstanceToUnit( 'Demo', 'TDemo', FDemo );
This looks a promising routine to call but I get an AV from an uninitialised unit table. I've also looked in the unit test code of the SVN source to see the use of this function but to no avail. Can anyone point me at what I should add / change?
ExposeInstanceToUnit has to be used from within the TdwsUnit table initialization, see RTTIExposeTests/ExposeInstancesAfterInitTable for some sample code. It allows directly exposing dynamic instances.
The other approach is to use the Instances collection of a TdwsUnit component, you get design-time support, and more controls over your instances and their lifetime.
Also keep in mind you have to make sure the instances you expose will properly behave even if the script misbehaves, f.i. when the user attempts to manually destroys an instance you exposed, and that instance shouldn't be destroyed. By default ExposeRTTI will map the destructors, so you may want to restrict that by specifying eoNoFreeOnCleanup.
edit: a last approach recently added is to use the TdwsRttiConnector, which basically allows exposing and connection to anything that's reachable through RTTI. That's very lightweight in terms of code to setup, but the downside is you don't get any form of compile-time checks.
I would like to do coloring in Eclipse without using the presentation reconciler. Therefore, first, I need to figure out how to associate a TextPresentation object with either my editor or document, but I am having difficulty finding out how to link it either of those. Normally, the CreatePresentation in the IPResentationReconciler interface would give the style range to the textpresentation, and from there Eclipse would know what to do with that presentation object. Is there some way to use a TextPresentation object without the use of PresentationReconciler? It would be nice if I could do coloring without the use of reconciler. Thank you.
I finally figured out how to achieve the coloring without the use of Reconcilers.
I discovered that first I needed a way to obtain a reference to my SourceViewer object, as I am extending TextEditor. I also discovered that I could implement the TextListener interface and add my own listener to the SourceViewer object. One must be careful, however, as calling the getSourceViewer() method can result in null if not called at the appropriate spot. Originally, I overwrote the init(...) function in my editor class and made the getSourceViewer() call, but it still resulted in null. After doing a bit of research, I discovered that I could properly obtain a reference to the SourceViewer object by overriding the createPartControl method. I first call super.createPartControl(...) and then make a call to getSourceViewer(). After I obtained that reference, I used that with my listener class I created and was able to do the coloring myself with the setTextColor method the SourceViewer object has. Hope this helps others in the same situation.