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I am trying to humbly port "FastLED + ESP8266 Web Server" by Jason Coon: https://github.com/jasoncoon/esp8266-fastled-webserver to ESPAsyncWebServer, with a few extra goodies...
My project is located here https://github.com/kelexel/esp8266-fastled-async-webserver-2.0/
My main work on this project is to wrap everything into nice Classes, and try to afford some kind of modularity.
EDIT: As many pointed out in the comments bellow, what I try to accomplish is clearly wrongly illustrated. All I am looking for are ideas, code sample, docs, references, on what should be done, so I can learn and improve...
I am totally new to C++, so please, be indulgent..
What I am trying to accomplish is obtain what I, neophyte, can only explain as a collection of objects, each objects having a String name and method pattern. Said pattern should be a method of the ESPLedDriver.cpp Class
The issue resides in the fact that in ESPLedDriver.h and ESPLedDriver.cpp, I try to create a Struct that references ESPLedDriver::
I made a snippet of the code to illustrate the issue:
ESPLedDriver.cpp
void ESPLedDriver::colorwaves()
{
// ...
}
void ESPLedDriver::palettetest()
{
// ...
}
void ESPLedDriver::setPatterns()
{
// const uint8_t patternCount;
_patterns = {
// ERROR: src/ESPLedDriver.cpp:225:3: error: cannot convert 'ESPLedDriver::colorwaves' from type 'void (ESPLedDriver::)()' to type 'ESPLedDriver::Pattern {aka void (*)()}'
{ colorwaves, "Color Waves" },
// ERROR: src/ESPLedDriver.cpp:225:3: error: cannot convert 'ESPLedDriver::palettetest' from type 'void (ESPLedDriver::)()' to type 'ESPLedDriver::Pattern {aka void (*)()}'
{ this->palettetest, "Palette Test" },
};
}
ESPLedDriver.h
#include "FastLED.h"
class ESPLedDriver
{
public:
ESPLedDriver();
// ...
private:
void setPatterns();
typedef void (*Pattern)();
typedef Pattern PatternList[];
typedef struct {
Pattern pattern;
String name;
} PatternAndName;
typedef PatternAndName PatternAndNameList[];
/* Patterns */
void colorwaves();
void palettetest();
PatternAndNameList _patterns;
uint8_t _patternCount;
}
(Or if you prefer, as a gist:
https://gist.github.com/kelexel/ab5687cf83e376c709e49fbfbcfc100b )
If all of the objects are string and pattern, you can model them as an abstract base class:
class String_Pattern
{
public:
virtual void pattern_method(ESPLedDriver& driver_to_use) = 0;
private:
std::string text;
};
Note that this design requires passing the driver to the string pattern object. Think of this giving the object a driver to use.
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I implemented a new class (ProtoType) in my header file. Which looks like this:
class ProtoType : public Test
{
public:
uint32_t test();
};
class RealProtoType : public Real
{
public:
uint32_t real();
};
Then in C++ file I made this
uint32_t ProtoType::test()
{
return 5;
}
uint32_t RealProtoType::real()
{
uint32_t holder = ProtoType::test();
}
Then I get this error when compiling
error: cannot call member function ‘uint32_t ProtoType::test()’
without object uint32_t ProtoType::test();
But I still fail, how can I resolve this?
Since ProtoType::test() is a non-static member function you need an object of type ProtoType to call the function upon:
uint32_t RealProtoType::real()
{
ProtoType foo;
uint32_t holder = foo.test();
return 42;
}
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I am reading a sample code that uses C++ and classes, I am new on C++ classes I can work with basics similar to this http://www.cplusplus.com/doc/tutorial/classes/, but I cant understand what the code below does mean or the color it is using visual studio c++
thanks
I am sorry if it is a fool question
It creates an object named some by instantiating the class some.
Then it calls the member function ToVector() on the object some and pass the result of the call to the function named function.
class is blue because it is a keyword of the C++ language.
The first some is green because it is the name of a class.
The second some is black because it is a variable.
And function and ToVector are red because the are functions.
Now this is ugly code because you "hide" the class some by reusing the same name for your variable. Also you do not need to put the word class here.
Here is a more complete and nicer version:
#include <vector>
class Some
{
public:
std::vector<int> ToVector()
{
return std::vector<int>(); //return an empty vector
}
};
int f(std::vector<int> v)
{
return 0;
}
int main(int, char**)
{
Some some; // Was "class some some"
return f(some.ToVector());
}
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I have a struct defined in a header file. Then I have a singleton class where I am trying to use the struct. When I call ResetVars() from another class I get an access violation when it hits the line that says test.numResponses = "TEST". I am assuming this has something to do with initialization but I haven't been able to solve it. I am new to c++ and I have no idea how to get around this. Thanks for any help.
struct.h
typedef struct POLL_DATA
{
std::string numResponses;
std::string type;
std::string question;
} POLL_DATA;
ControlPolls.h
class ControlPolls
{
private:
static bool instanceFlag;
static ControlExitPolls *controlSingle;
ControlExitPolls();
POLL_DATA test;
public:
static ControlExitPolls* getInstance();
void ResetVars();
};
ControlPolls.cpp
#include "ControlPolls.h"
bool ControlPolls::instanceFlag = false;
ControlPolls* ControlPolls::controlSingle = NULL;
//Private Constructor
ControlExitPolls::ControlExitPolls()
{
};
//Get instance
ControlPolls* ControlPolls::getInstance()
{
if(!instanceFlag)
{
controlSingle = &ControlPolls();
instanceFlag = true;
return controlSingle;
}
else
{
return controlSingle;
}
}
void ControlExitPolls::ResetVars()
{
test.numResponses = "TEST";
}
callingClass.cpp
ControlPolls *controlSingleton;
controlSingleton = ControlPolls::getInstance();
controlSingleton->getInstance()->ResetVars();
You've been struck by C++'s Most Vexing Parse, a compiler rule that says anything that could be a function declaration is a function declaration. The culprit is this line:
POLL_DATA testPoll();
testPoll is treated as the declaration of a function with return type POLL_DATA. Try removing the brackets, or writing simply POLL_DATA testPoll; which implicitly calls the compiler-generated default constructor.
Another larger problem is that testPoll is a member of A, but you've hidden it and declared a local variable in your constructor, A::A(). I suggest you remove the constructor altogether because the implicit constructor will suffice.
Some more notes on your code:
You've declared your class a but refer to it later as A.
You've written an implementation of a constructor for A without declaring it like a proper forward declaration.
Also, typedef struct is not needed in C++. It is sufficient and encouraged to write:
struct POLLDATA {
...
};
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Still getting my head around C++ as I'm new to it, but I'm trying to extend some existing code I've got that is expecting me to make use of the std::vector.
The following is declared in the header (shortened for simplicity):
class WindowManager
{
private:
std::vector<Item*> m_itemlist;
}
My problem is how I'm meant to access this from the .cpp? I'd like to use it to have an array of Item type but I don't understand how to actually get to the point where I can add a newly instantiated Item, let's say button, to the array?
A bit of a rudimentary question but I've not had much luck with tutorials that cover std::vector.
If possible avoid using vector of pointers to Item. Use vector of Item directly.
class WindowManager
{
void addItem(Item const& item) { m_itemlist.push_back(item); }
private:
std::vector<Item> m_itemlist;
};
int main()
{
WindowManager wm;
Item i;
wm.addItem(i);
}
To add an item you could use a member function like this:
class WindowManager
{
private:
std::vector<Item *> m_itemlist;
public:
void addItem(Item *newItem);
}
in window_manager.cpp:
void WindowManager::addItem(Item *newItem)
{
m_itemlist.push_back(newItem);
}
see std::vector::push_back()
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I have a class that looks like this,
class A
{
std::shared_ptr<Type> ret;
public:
A()
{
ret=std::shared_ptr<Type>(new Type);
}
std::shared_ptr<Type> GetTypeA(){return ret;}
A (const A&a)
{
....
ret=a.ret;
}
};
class Type
{
A aa;
public:
Type(A*a):aa(*a){}
};
Somewhere in the client code, I call the method GetTypeA like this
void func(A*pA)
{
...
std::shared_ptr<Type> spT=pA->GetTypeA();
...
}
Debugging shows me that spT=empty after the call. But inside pA, ret value is NOT empty.
I notice some mistakes in your code :
A()
{
ret=std::shared_ptr<Type>(new Type);
}
"new Type" means you call default constructor for Type (Type::Type()), and you didn't write it in your sample. Try "new Type(*this)" to use your own constructor.
But to do this you need to change your Type class to:
class Type
{
A* aa; // Use a pointer
public:
Type::Type(A&a) :aa(&a){} // Use references
};
The problem is it's not resolving the "recursive aspect", depend your needs, I would use a static reference to A in the Type class...