I am switching scenes when my character wins or loses the game. I get a message saying a pointer being freed was not allocated.
Sometimes, the game does not crash and it goes back to the game view. But sometimes the game crashes in the main on this line:
int retVal = UIApplicationMain(argc, argv, nil, #"AppController");
the error being "bad access";
I switch to the end screen using the CCdirector:
cocos2d::CCDirector::sharedDirector()->replaceScene(GameWon::scene());
Then in the GameWon.cpp I create a new game scene to start a new game:
cocos2d::CCDirector::sharedDirector()->replaceScene(Controller::scene());
No idea what causes this problem. The weird thing is that, it doesn't always crash on the simulator. Any tips?
edit
So I found out what the problem is, I just don't know why it's a problem. Apparently the destructor of my Controller is called when I create a new scene. In this destructor I free my model object:
Controller::~Controller()
{
free(pModel);
}
When I don't free the model object it works like a charm. However, in the init of my constructor I do this:
pModel = Model::create();
So I'm not sure why the pModel would be a pointer that is being freed, but not allocated?
My guess is that you did not retain retain your pModel object. Create function usually autoreleases the object and if you do not retain it, it will be deleted by the time you call "free(pModel)" in the destructor.
you need not to free your pModel object manually in the destructor as in the create function the object being created is added to the autorelease pool . So what happens here is that first when the autorelease pool drains it automatically deallocates the memory allocated to the pModel . And when the controller's destructor is called free(pModel); tries to free the memory which is already freed.
When you replace scene, The destructor of previous scene is called. If you free the object created with create() function of cocos, as it’s already added in autorelease pool managed by cocos, pool tries to release (delete) already deleted(in destructor using free) pointer. so, Don’t use manual delete to cocos objects created using create functions.
Related
I have an interface that represents a pointer to a struct object after it has been initialized. I want to get access to the Value of the object that the interface references rather than the pointer so that I can pass it by value to a function as the interface type.
Here is an example of my issue: https://play.golang.org/p/_3vKThlj-V
I want to be able to pass val by value to the function EvalTest in my main function so that I can overwrite the pointer to the TestStruct object in another thread without causing pointer dereference issues in another thread.
The problem is that I'm running several thousand go routines against my interface object, but every 50 go routine calls I have to re-initialize my pointer due to a constraint of the system I'm integrating with. This seems to be leading to an inconsistent state where the new struct initialization is not completely finished when the go routines attempt to access it again. So the reason I wanted to pass it by value was so that I don't have to worry about the pointer being swapped out.
Any thoughts on this?
This was solved by utilizing a channel for my integration api connection and passing a new pointer down the channel whenever it was successfully initialized. There were also some other optimizations that I was able to use to ensure that I was only replacing the pointer in the event of a successful connection. Here is an example of what I used that I got from Paul K in the Go slack channel.
https://play.golang.org/p/AmbsfQOzol
I am building a WinRT App, that uses proximity, and WiFi direct for peer to peer communication. As a result, when the app terminates, and then resumes I need it to start fresh (the connections will be closed, and can't be reopened without user interaction). The problem is that the Prism MvvmAppBase class that I am inheriting my app from is doing something that is causing it to try to resume from a saved state (that does not exist) and the app ends up on the last screen shown, but there is no ViewModel backing it, and so depending on the view, it will just sit unresponsive, or crash.
I am looking at this guide for guidance, and it says that unless there is a way to start fresh, but I cannot seem to find how to actually do that. http://msdn.microsoft.com/en-us/library/windows/apps/xx130647.aspx
I have been hacking around in the App.cs file to try and get it to work. There is really nothing at all in the App.cs file now except for the unity container and prism bootstrapping, and a call to NavigationService.Suspending() in the Suspending event handler.
The bootstrapping looks like this, but it is never called when the app is resumed from Termination.
protected override async void OnLaunchApplication(LaunchActivatedEventArgs args)
{
await BootStrapper.Config(_container);
await BootStrapper.RegisterPrismInstances(_container, NavigationService, SessionStateService, FlyoutService);
NavigationService.Navigate("Main", null);
}
If anyone has dealt with this before, and can point me in the right direction, I would really appreciate it.
When a Prism WinRT app is re-launched after being Terminated Prism will try to restore the application state, the Frame's navigation stack and the Frame's state before being terminated (which will navigate to the last opened page and try to restore any properties in the view model that are marked with the RestorableState attribute.)
By looking at the MvvmAppBase's source code it seems that there are a couple of things you could try to prevent Prism for saving / restoring the application state:
Create a default constructor in your App class that would clear the handlers of the Suspending event. The default constructor of the MvvmAppBase registers to this event and saves the state when it's raised.
Override the OnLaunched method of the base class. In it, after executing the base method, check if the previous executing state is Terminated. If so, you could clear the navigation history of the NavigationService and navigate to your start up page. The saving and restoring operations will still execute though, so any registered service will still be restored to its previous state. (This cannot be done in the OnLaunchApplication as it's not invoked if the application's state was successfully restored.)
Also, you could also try to completely remove this functionality from the MvvmAppBase class. However, most of its methods related to saving / restoring the application state are private, so you might as well drop the MvvAppBase, copy its entire code in your App class and edit it accordingly.
I have not tried any of the approaches listed above so I'm unaware if they could generate any problem, but they might help you as a starting point.
I have an object (MovieClip) on stage at some frame, and at the next frame, even though the object is visually removed, it is still there (it has an internal function that generates something on stage periodically, and the stage objects are being generated). I know I can simply stop the action while leaving the frame, but the object will eat up memory and maybe even CPU time for some background actions (and this is a AIR to iOS project so I care about memory and performance). How can I get rid of the object entirely? I expect everything to be removed when I navigate to another frame if it's a designer-placed object (if the object is not generated by ActionScript) and this is the case, but it only gets visually removed.
Thanks,
Can.
Just null your object reference and it's listeners.
...
myMovieClip.removeListeners();//class function
myMovieClip.parent.removeChild(myMovieClip);
myMovieclip = null;
...
I'm working with Progress 10.1c
I have a class that contains both static and non-static methods.
The class is defined with USE-WIDGET-POOL. In the destructor I say "DELETE WIDGET-POOL".
I create an instance of my class, and call a method. The method itself uses one of the static methods of the class. So if I understand it correctly, I will now have the instance of my class in its own unnamed pool, and a separate unnamed widget pool for the static members of the class.
So far so good. But I'm busy debugging and I'm making changes to the code. I recompile and run my test again. Now my non-static members work, but all the static members come from the older version of my class, that is still stored in the pool for static members, which is scoped to the session. In other words, the "DELETE WIDGET-POOL" in my destructor deleted the pool for the instance of the class, but the pool for the static members is still there.
The only way I can get it to load the new version of my class is to log off my session, and log on again. This is quite a mission in our environment. Every time I make a change, I have to stop and start my development environment.
I tried to walk the list of objects in my session, but could not find what I'm looking for. There's a good chance I'm starting at the wrong object, or I'm missing some knowledge of pools and objects in Progress.
Is there any way for me to target that unnamed pool and delete the static "instance" of my class, without destroying my session every time?
This turned out to be doable with very little coding. I can use the statement DELETE OBJECT THIS-OBJECT to delete the instance executing that statement. So if it's in a static method, it is the static instance that gets deleted.
METHOD STATIC VOID Reload () :
DELETE OBJECT THIS-OBJECT.
END METHOD.
So now when I have a new version of the class, I just use MyClass:Reload(). No need to end my session.
Thanks to Tim Kuehn for pointing me in the right direction with his suggestion of using a static method to delete the named widget-pool.
I have created this example to demonstrate how I got it to work. Below is a simple class with 3 static methods:
/* File : rtt/cls/demo.cls */
USING Progress.Lang.*.
ROUTINE-LEVEL ON ERROR UNDO, THROW.
CLASS rtt.cls.demo USE-WIDGET-POOL :
METHOD STATIC CHARACTER SayHello() :
RETURN "Good-bye".
END METHOD.
METHOD STATIC VOID ShowMessage() :
MESSAGE "This is the message." VIEW-AS ALERT-BOX.
END METHOD.
METHOD STATIC VOID Reload() :
DELETE OBJECT this-object.
END METHOD.
END CLASS.
I don't know how other people's environments are set up, but in my environment I have to log on to our system to be able to compile and run programs, in other words, I have an active session.
So I compile the file:
COMPILE VALUE(SEARCH("rtt/cls/demo.cls")) SAVE.
And then I run the following bit in Procedure Editor to test it:
USING rtt.cls.*.
demo:ShowMessage().
MESSAGE demo:SayHello().
When I run this, I get a message box that says "This is the message.", followed by a message box that says "Good-bye". Exactly as one would expect.
But there's a bug, it's supposed to say "Hello", not "Good-Bye", so I edit my class (I'm only showing the two methods I'm changing:
METHOD STATIC CHARACTER SayHello() :
RETURN "Hello".
END METHOD.
METHOD STATIC VOID ShowMessage() :
MESSAGE "That was the message." VIEW-AS ALERT-BOX.
END METHOD.
I save my changes, compile it as before, and I run the test again. What messages do you expect to see? I expect to see "This is the message." and "Good-bye", same as before. That's logical, because there is a hidden widget-pool in my current session, and it has an instance of my class loaded (from my first test). It will keep on using this instance until the instance or the pool is destroyed. So I shut down my development environment, log off and then log on again to start up a new session. So far everything is working exactly as expected.
Now I run my test again, and sure enough, I get my new version: the messages are "That was the message" and "Hello".
But now I'm told to add an exclamation after the word "Hello". so I change it:
METHOD STATIC CHARACTER SayHello() :
RETURN "Hello!".
END METHOD.
I save it and compile it. When I run the test, obviously I will get the older version that says "Hello" without the exclamation. I have to restart my session again before my changes become active. I really don't want to do that again. So I change my test as follows:
USING rtt.cls.*.
demo:Reload().
demo:ShowMessage().
MESSAGE demo:SayHello().
I run it and voilà, I get my latest changes. I change the message from "That was the message" to "It works!". I save, compile and run my test. What do I see? I see "It works!". No more restarting my session between edits. My solution works perfectly for me.
I tried all sorts of stuff, but I cannot get it to generate the error "Cannot Reference THIS-OBJECT or SUPER from a static member (15071)".
Static class elements last for the duration of the ABL session, and the only way to 'unload' them is to have a database connection go down (ie, the db server is shut down). This unloads everything, clears the client code, and leaves you in the 4GL editor.
Beyond that, the only other possible way is to create a named widget pool for the static class, then call a (static) method to delete that. I have no idea if this would work or not.
"Static members that are scoped to the class type. This unnamed widget pool is implicitly
deleted only when the ABL session in which the widget pool is created terminates."
http://documentation.progress.com/output/OpenEdge102b/pdfs/dvoop/dvoop.pdf
page 5-9
In this case make you something wrong. You should use the static members only for methods or properties, which are realy static and must be not deleted or reinitialised when is deleted the instance of class.
when you will use it anyway, you should define your own static widget-pool with name and any static dynamic objects create in this widget-pool. then can you in Reload() write:
METHOD STATIC VOID Reload () :
DELETE WIDGET-POOL XYZ.
CREATE WIDGET-POOL XYZ.
END METHOD.
other way is to use a singelton class, where are defined this 'static' objects. then anytime, when you will, you can delete the instance of this singelton and make some new fresh.
Let suppose I create a class, and in this class I declare a method that will run a loop.
My question is what will be behavior of loop, if I dispose the object of class and condition of loop is yet true - will loop execute or terminate.
Usually the object (variable) is managed by a single thread. So you may not be able dispose of easily because the thread is still running in the loop. If you mult-thread and you call in a method that modifies this variable (your object) on the a different thread you may crash your program. If your loop in a UI thread which has a message pump (sta thread) and you call a method directly from another thread then you app will crash as this is not allowed.
All in all what do you want to do ? Mark Byers's condition "The code keeps running" is the most possiable outcome of this I think. But you have a bug either way - don't attempt to drive a car and then just jump out of it without stopping.