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[on:]

Is it possible to make a class in a .pde file? Something like this processing example? http://webzone.k3.mah.se/projects/arduino-workshop/projects/arduino_meets_processing/instructions/accelero.html
When I make a new tab in which I make a class arduino say's: "error: 'OneWireLib' does not name a type" Here is "OneWireLib" the name of the .pde file and the class.
For now the class is virtually empty:

Code:

class OneWireLib
{
OneWireLib()
{
  int y =1;
}
void ConvertTemp()
{
  int x =1;
}
}

In my main program I call the class like this:

Code:

OneWireLib owl;

[Reply #1 on:]

I see a few things that might help:
- Make sure you put a semicolon ';' after the final '}' in the class declaration.
- you will need to make some things "public" if you access them from outside the class.  By default, members of a class are "private".
- You should declare variables as members of the class if they are part of the object.

Here is an example of what I mean:

Code:

class OneWireLib
{
public:
    OneWireLib()
    {
        int y =1;       // this 'y' will go away once the constructor returns (it is a local variable)
        somevar = 99;     // initialize class member variables here in the constructor
    }

    void ConvertTemp()
    {
         int x =1;
    }

    int GetSomeVar()    // example of method for using private data
    {
        return somevar;
    }

private:
     int somevar;      // put variables that are part of the object here
};        // <===  note semicolon here... terminates the class declaration

OneWireLib  onewire;     // declare an instance of the OneWireLib class

void setup()
{
    int x = onewire.GetSomeVar();     // example of calling a class method
}

[Reply #2 on:]

I tried you're example using a second tab and it doesn't work. This is the error:
error: 'OneWireLib' does not name a type In function 'void test()':


But, if I try it in one file it does work. What's the difference? I tried to #include the file but it is not found.

[Reply #3 on:]

Please post your code and I will see if I can help.

[Reply #4 on:]

The mainfile testclass.pde:

Code:

// #include "onewire.pde"

OneWireLib  onewire;     // declare an instance of the OneWireLib class

void setup()
{
    int x = onewire.GetSomeVar();     // example of calling a class method
}
void loop()
{
}

and the class file onewire.pde:

Code:

class OneWireLib
{
public:
    OneWireLib()
    {
        int y =1;       // this 'y' will go away once the constructor returns (it is a local variable)
        somevar = 99;     // initialize class member variables here in the constructor
    }

    void ConvertTemp()
    {
         int x =1;
    }

    int GetSomeVar()    // example of method for using private data
    {
        return somevar;
    }

private:
      int somevar;      // put variables that are part of the object here
};        // <===  note semicolon here... terminates the class declaration

the onewire.pde file is in the same directory as the testclass.pde file.
And again, all this code in one file does work.

[Reply #5 on:]

OK, now I understand.  I too have had problems trying to #include a header file in the same directory as my sketch.  Looks like Arduino does NOT put the sketch directory inside the C++ include path.  But it looks like maybe you are trying to make a reusable library.  Try taking a look at this:

http://www.arduino.cc/en/Main/Libraries

[Reply #6 on:]

I didn't start the thread for a reusable library. It was more to get my code more readable. So I figured that a class in another tab would be helpful. After reading this http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1167857708 thread I figured it would be easy to do.  

[Reply #7 on:]

If the #include statement uses "double quotes", the compiler will check the directory that the including file is in (i.e. the sketch directory).  You just need to add to your sketch a .h file with the appropriate contents, and place the #include statement at the top of the main sketch file, and you should be fine.

[Reply #8 on:]

But is this .h necessary? If you start a new tab the file will be saved as a .pde file. So, I expected that a #include  "onewire.pde" would work, but it doesn't.


Okay, I tried it. If I rename the onewire.pde to onewire.h and I use "#include "onewire.h" it works. And it gets better, if I save the file als foo.h it won't get the pde extension. But this might be something platform specific? (I am on OSX)
So, only one question left: why does .h work and .pde not?