Class declaration problem with constructor

Using Arduino Programming Questions
1

I want to calculate the days that passed in a year since a certain date. I made a class DayNumber.
i made this header file

#ifndef DayNumber_H_
#define DayNumber_H_


class DayNumber
{
	private:
		int _day1YearLoop[];
		int _day4YearLoop[];

	public:
		int Days1YearLoop;
		int Days4YearLoop;

	DayNumber(int setYear,int setMonth,int setDay);
	virtual ~DayNumber();

	bool checkLeapYear(int setYear);

};

#endif

i use eclipse. and i made this .cpp file.

#include "DayNumber.h"


DayNumber::DayNumber(int setYear,int setMonth,int setDay){

// it does not matter what it does it just give me the number of the day since 1 january of each year for a certain day.

	
}


DayNumber::~DayNumber(){
}


bool DayNumber::checkLeapYear(int setYear){
	if (setYear%4==0){
		return true;
	}
	else{
		return false;
	}
}

the problem is at the main.cpp. When i do:

void loop() {

	  DayNumber num1 = DayNumber(2715,10,23);

	  Serial.print("Days for one Year Loop(leap)\t");
	  Serial.print(num1.Days1YearLoop);
	  
	  delay (5000);
}

everything is ok. if i try to declare DayNumber num1; befroe everything. i mean before setup like this:

#include "Arduino.h"
#include "DayNumber.h"

DayNumber num1;

int main(void)
{
	init();
	setup();

	for (;;)
		loop();

	return 0;
}

void setup() {                

  Serial.begin(9600);
}

void loop() {

	  DayNumber num1 = DayNumber(2715,10,23);

	  Serial.print("Days for one Year Loop(leap)\t");
	  Serial.print(num1.Days1YearLoop);
	
	
	  delay (5000);
}

i get this error:
../src/main.cpp:8: error: no matching function for call to 'DayNumber::DayNumber()'
/Volumes/Lion 2/EclipseWorks/DayNumber/lib/DayNumber.h:22: note: candidates are: DayNumber::DayNumber(int, int, int)
/Volumes/Lion 2/EclipseWorks/DayNumber/lib/DayNumber.h:12: note: DayNumber::DayNumber(const DayNumber&)
make: *** [src/main.o] Error 1

line 22 at header is DayNumber(int setYear,int setMonth,int setDay);
and line 12 is class DayNumber{

so why is this happening? i did everything by the tutorial of from the site and i mean arduino for making libraries. I just wanted to define an "object" of this class to use it in loop.i have made an RTC (real time clock) and i am also using its library that does the same ( defines the object of RTC class before everything) and it does not give any problem. Can you give me a solution so i can declare the object without initialization and then call it inside loop and initialize it?

2

try that

DayNumber num1 = DayNumber(2715,10,23);

int main(void)
{
	init();
	setup();

	for (;;)
		loop();

	return 0;
}

Problem: way of declaration.

if you really like that way declaration DayNumber num1;

then add one more constructor.

DayNumber(int setYear,int setMonth,int setDay);
DayNumber();
3

The DayNumber class needs a constructor that takes no arguments, and a method that takes the arguments of interest, and returns the value of interest.

4

It should be possible to give default values to the arguments in the constructor and then it would at least pass compilation, but I doubt this is what you wanted either.
DayNumber(int setYear = 2715,int setMonth = 10,int setDay = 23);