I've been trying to get the acceleromter to work in cocos2d-x c++.
I tried to add this function to my scene which a lot of my Google search results said I should:
virtual void didAccelerate(Acceleration *acceleration);
That does however give me an error saying I'm overriding a final function.
Then I found how I could use the EventDispatcher thing for it.
auto accListener = EventListenerAcceleration::create(CC_CALLBACK_2(MainScene::accelerated, this));
getEventDispatcher()->addEventListenerWithSceneGraphPriority(accListener, this);
In both of these I had called this function earlier in my scene's init function:
setAccelerometerEnabled(true);
I'm all out of ideas and I need help. On the second "approach" it compiled, but my accelerated function was never called.
Thank you in advance!
I'm using Android so maybe I need to edit something in the AndroidManifest?
The guys at the cocos forums linked me to this:
Cocos docs
As you can see the correct way to go is to use the EventListener approach as described earlier. However you need to call
Device::setAccelerometerEnabled(true);
Calling
setAccelerometerEnabled(true);
From the scene's init doesn't work, you need to call the static method on 'Device'.
So here's how you do it.
Device::setAccelerometerEnabled(true);
auto accListener = EventListenerAcceleration::create(CC_CALLBACK_2(MainScene::accelerated, this));
getEventDispatcher()->addEventListenerWithSceneGraphPriority(accListener, this);
Where accelerated is takes these parameters:
void accelerated(Acceleration *acceleration, Event *event);
Of course this function can be called anything as the EventListener takes a function pointer.
Tritzium answered it right. Just wanted point out:
You wont get accelerator events in simulator, you need a device.
Related
I would like to have a window, in which a picture changes depending on what is happening during an infinite loop.
Imagine someone walking around and when he leaves a given track, the program should display an arrow towards the direction of the track. Therefore I have a program, which determines the distance between user and track, but I have no idea on how to update the image.
I use code::blocks with wxWidgets and think I have to use the wxStaticBitmap class. (If there is a better way, please tell me.)
I tried with:
while(true)
{
updatePosition();
if(userNotOnTrack)
{
if(trackRightOfUser)
{
StaticDirectionBitmap->SetBitmap("D:\\WindowsDgps\\WindowsDgpsGraphic\\arrow_right.png");
}
}
}
(Note that this snippet is mostly pseudocode, except the StaticDirectionBitmap part.)
On default the Bitmap has a "no_arrow" image. With this I get an error: error: no matching function for call to 'wxStaticBitmap::SetBitmap(const char [51])'|. I see from the documentation that this cannot work, but I have no idea what could.
If anyone knows how to handle this, I would be happy to hear. I remember a few years back, when I tried something similar in C# and failed completely because of thread safety... I hope it is not this hard in C++ with wxWidgets.
SetBitmap takes a wxBitmap parameter not a string. So the call should look something like:
SetBitmap(wxBitmap( "D:\\WindowsDgps\\WindowsDgpsGraphic\\arrow_right.png", wxBITMAP_TYPE_PNG) );
Make sure prior to making this call that the png handler has been added with a call like one of the following:
wxImage::AddHandler(new wxPNGHandler);
or
::wxInitAllImageHandlers();
The easiest place to do this is in the applications OnInit() method.
If you want update the static bitmap from a worker thread, you should throw a wxThreadEvent and then make the call to SetBitmap in the event handler. The sample here shows how to generate and handle these events.
In my scene I have a vector with multiple custom sprites. When I tap on one of them, I want an action to be fired on another element on the scene, can be another sprite in the vector, or another node. I have been researching the best way to do this, but I'm not quite sure how to implement it. The options are:
Add a touch listener to the scene, and verify if it was tapped inside the bounds of the sprite with rect. containsPoint(point). And after that, I have to get the sprite that was tapped to do the action I want. For me, it doesn't seems very clean to do it this way. And if two sprites are overlaped, I have to verify if the sprite is behind or in the front in order to retrieve the desired sprite. I followed this example: Touch Event example
Add a touch listener in the subclass of the sprite (my custom sprite). And add onTouchBegan and onTouchEnded inside it. But this way, I don't know how to modify an attribute of another sprite, or another element in the scene (Is it possible to use Delegates like Objective-C does?). I followed this example: Subclass Sprite Example
My main problem is that I don't understand very well how to make a node interact with another node in the scene. I have seen a lot of tutorials, but in all of them, when you interact with a node, it only changes its attributes, not other nodes' attributes.
Thanks in advance.
I shall propose "EventCustom" way :)
You can add in your touchBegan / touchEnded methods (wherever you put them... you got the point...) additional code for passing an EventCusto to the _eventDispatcher and get it announced to the world ;)
EventCustom *e = new EventCustom("MyAwesomeEvent");
e->setUserData(ptrMyFantasticData); //This function takes a void pointer. cheers :)
_eventDispatcher->dispatchEvent(e);
You may subclass the EventCustom class but that is hardly necessary. You can always hang an object to it with setUserData().
Now the objects which need to react to the event can listen to it by
_myCustomListener = EventListenerCustom::create(
"MyAwesomeEvent",
CC_CALLBACK_1(
ListeningClass::onMyAwesomeEvent,
this
)
);
_eventDispatcher->addEventListenerWithXXXXXPriority(_myCustomListener, XXX);
//ScreenGraphPriority / FixedPriority depends on situation. Either should work.
It's always a good practice to remove your listeners when you go off, so somewhere, perhaps in onExit(), where you removed touch listeners remove this listener too, as
_eventDispatcher->removeEventListener(_myCustomListener);
Going a bit off the track, a clarification:
CC_CALLBACK_X are a bit tricky names. The X indicates the no. of args the target function will get. Here, event dispatcher will pass 1 arg i.e. ptr to object of EventCustom you handed it, so we use CC_CALLBACK_1. The next arg - here "this" - is the object on which the method will be invoked.
In short, we may say that this callback is going to result into a function call this->onMyAwesomeEvent(e);
For CC_CALLBACK_2 onwards, we can specify additional args, 3rd arg onwards.
Coming back to the issue at hand, ListeningClass::onMyAwesomeEvent will look something like
void ListeningClass::onMyAwesomeEvent(EventCustom *e)
{
MyFantasticData *d = (MyFantasticData *) e->getUserData();
CCLOG("[ListeningClass::onMyAwesomeEvent] %d", d->getMyPreciousInt());
}
Hope it helps :)
Set your elements tags or names with setTag and setName. Then if element x is touched, get them with getChildByTag or getChildByName and do what you need to do.
With the second option you list above.
To make a node interact with another node in the scene you can add touch callback function to your custom sprite object like that:
https://github.com/Longpc/RTS/tree/master/Classes/base/dialogBase
and in main scene you can define function to handle this callback. So you can do every thing to unit in you scene
I'm trying to make a custom sprite, which could receive touch and handle the function as callback.
Okay, first step, receive the touch, easy, we can search it online everywhere.
The one I couldn't do is, I want to make it receive SOMETHING in the class the sprite is created, a function that will be called when the sprite is touched.
I was searching on internet and I think (not really sure) that SEL_Callfunc can do what I want, but I couldn't understand how this one work, so can you guys give me an example please?
For example, my custom class is BSprite, so when I create new object in HelloWorld.cpp, it should be
BSprite* sprite = BSprite::create("HelloWorld.png",HelloWorld::TouchCallback);
Thanks for reading :)
sprite->addTouchEventListener(CC_CALLBACK_0(HelloWorld::onTouchSprite, this));
void HelloWorld::onTouchSprite() {
}
Note: onTouchSprite method should not have any parameters
I connected C++ and QML via a mediator-class and have everything working in both directions but this one puzzles me.
This is how I connect the mediator-class:
// Initialize Mediator between QML and C++
QmlCppMediator m_qmlCppMediator;
QDeclarativeContext *context = viewer.rootContext();
context->setContextProperty("cppInterface", &m_qmlCppMediator);
How to fire off an ordinary Property-Animation from within C++ ?
Ok I can answer this myself already.
I went for an approach described here http://qt-project.org/doc/qt-4.8/qdeclarativeanimation.html
I bind the “state” of the object which I try to animate to a Q_PROPERTY in the C++ interface.
The different states are linked to transitions (in QML) which do the animate the object.
Rather an easy way would be to define a JavaScript function inside the QML file itself, lie this:
function startAnimation() {
animationID.running = true;
}
Now call this code from C++, simple!
My friend and I have each created parts of a GUI using Qt 4. They both work independently and I am trying to integrate his form with the my main window. As of now this is the code I am using to try and load his form:
//connect buttons and such
connect(exitbtn, SIGNAL(triggered()),this,SLOT(terminated()));
connect(add, SIGNAL(triggered()),this,SLOT(add_rec()));
void MainWindowImpl::add_rec()
{
//form quits as soon as it loads...?
DialogImpl dia;//name of his form
dia.show();
}
I have included his header file. The program compiles but when I hit the trigger his form loads up for maybe half a second and then closes. Does anyone know what I am doing wrong?
You have almost get it right. This is because the RAII of C++. If you allocate the Dialog on stack, it would be destructed as soon as the function return.
Assuming MainWindowImpl inherits publically from QWidget, you're looking for this:
void MainWindowImpl::add_rec()
{
// passing "this" to the constructor makes sure dialog will be cleaned up.
// Note that DialogImpl will need a constructor that takes a
// QObject* parent parameter.
DialogImpl* dialog = new DialogImpl(this);
dialog->show();
}
Look at the Qt documentation for examples of how the constructors should look.
Apparently QT4 only allows one instance of an object at a time, however pointers are another matter. Change both the main.cpp and what ever your main window to look something like this:
DialogImpl *dia=new DialogImpl;
dia->show();