Methods not visible in self made library

Answers

• jeremydouglass

  November 2016

  "is not visible"

  Did you make it public?

  Rule of thumb -- if you are used to writing in Processing, get used to writing public in front of almost everything in your Java library.
• jeremydouglass

  November 2016

  Ack -- sorry, you said it was public already, I somehow missed that part.

  Cut a test copy of your library down to a single empty class with that constructor. Do you get the same error? If so, share the code here.
• MrLumme

  November 2016 edited November 2016

  So, I removed all other classes from the .jar file than the QuickInteraction.class. I tested it again as before but added one of the missing classes, just but be sure:

  import quickInteraction.*;
  Button b = new Button();
  QuickInteraction qi = new QuickInteraction(this);
  

  As expected it gave a "The class Button does not exist" and the "The constructor QuickInteraction(PApplet) is not visible".

  This is the only class in the library:

  package quickInteraction;
  
  import processing.core.PApplet;
  
  public class QuickInteraction {
  
           public static final byte RECT = 0;
           // Lots of public static final bytes used as library constants
           public static final byte PROCENT = 14;
  
           public static PApplet parent;
  
           public QuickInteraction(PApplet parent) {
                QuickInteraction.parent = parent;
           }
  }
  
• quark

  November 2016 edited November 2016

  So, I removed all other classes from the .jar file than the quickInteraction.class.

  Java is case sensitive so I would have expected it to be QuickInteraction.class

  Also I assume you are building the library in Eclipse rather than just copying the class file into the sketch?
• koogs

  November 2016

  (hint: for posting blocks of code, highlight them and hit ctrl-o. don't rely on the backticks)
• GoToLoop

  November 2016

  public static PApplet parent;

  Field parent shouldn't be static! Sometimes folks go w/ multi-windows sketches. :ar!
• MrLumme

  November 2016 edited November 2016

  quark, it was a typo with the lower case letter, have fixed it in the previous comment. And yes, I am coding it in eclipse, and exporting the jar file from there.

  koogs, did not know, thanks.

  GoToLoop, the rest of the library depends on it being static, but I do find the multiple window aspect appealing. I'll change it once I find a good way to do so.
• GoToLoop

  November 2016 edited November 2016

  • Fix is just as easy as remove keyword static from field parent.
  • Unless you are indeed accessing parent as QuickInteraction.parent throughout your code.
  • If so, you're gonna need to replace QuickInteraction by an instance variable of it: qi.parent.
  • BtW, I find parent's too big for something that's gonna be used a lot.
  • I'd simply call it p or pa instead. :\">
  • Ah! I'd also declare it as final. >-)
• quark

  November 2016

  I agree having the parent as static is not needed but if you remove it you need to modify the constructor :-</p>

  package quickInteraction;
  
  import processing.core.PApplet;
  
  public class QuickInteraction {
  
           public static final byte RECT = 0;
           // Lots of public static final bytes used as library constants
           public static final byte PROCENT = 14;
  
           public PApplet parent;
  
           public QuickInteraction(PApplet parent) {
                this.parent = parent;
           }
  }
  

  As to replacing parent with p that is a matter of choice, although it saves typing having more descriptive variable names helps debugging large code bases and Eclipse does have auto complete. :)

  Having said all that I can see no reason why your sketch cannot find the constructor provided QuickInteraction is a top-level class i.e. defined in its own file 'QuickInteraction.java'
• MrLumme

  November 2016

  I am exactly accessing it as QuickInteraction.parent throughout the code so that every time for example a new button is made, it does not need it as a parameter.

  I would also have wanted it as a final but I as far I know finals have to be given a value immediately, and as such, I would not be able to set it in the constructor. Is this wrong?
• MrLumme

  November 2016

  But on the topic of it not working, could it be something other than the jar file? If I remember correctly in C++ you need a header file to define what methods you have in the library. But to my knowledge something like that is not needed in java nor processing, right?
• GoToLoop

  November 2016 edited November 2016

  ... as far I know finals have to be given a value immediately, and as such, I would not be able to set it in the constructor. Is this wrong?

  It is wrong... :-\" Field initialization can be delayed till class' constructor. \m/
  And for local variables, regardless they're final or not, they can be delayed just before they're 1st accessed. ~O)
• MrLumme

  November 2016

  And just to cover that front too, I just write the file structure:

  quickInteraction/
      library/
          quickInteraction.jar
      src/
          quickInteraction/
              QuickInteraction.java
      library.properties
      readme.txt
  

  And inside the .jar:

  quickInteraction.jar/
      META-INF/
          MANIFEST.MF
      quickInteraction/
          QuickInteraction.class
  
• quark

  November 2016

  There are no header files in Java or Processing.

  What is the name of the file (???.java) that has the code for the QuickInteraction class?
• jeremydouglass

  November 2016 edited November 2016

  File structure shows class folder does not match Java file name - q vs Q again. Seems like a recurring problem to check for. Methods are lowerCamelCase, classes are TitleCase -- and files match the classes they contain.
• MrLumme

  November 2016 edited November 2016

  What is the name of the file (???.java) that has the code for the QuickInteraction class?

  It is QuickInteraction.java

  I have also renamed all files and folders called quickInteractionto QuickInteraction just to be sure.

  The constructor, however, are not visible.
• GoToLoop

  November 2016 edited November 2016

  The "quickInteraction.jar" is still all lowerCamelCase! Rename it to: "QuickInteraction.jar".
  Try to recompile everything as well. And make sure the final result is: "QuickInteraction.jar".
• quark

  November 2016

  QuickInteraction qi = new QuickInteraction(this);

  Are you executing this statement inside the main sketch code or from inside another class?
• MrLumme

  November 2016

  Inside the sketch.
• quark

  November 2016 Answer ✓

  Create a new sketch and try and instantiate the QuickIteration object and if it doesn't work post the sketch code and the error message here
• MrLumme

  November 2016

  I tried to recompile it again this morning and now it works. I think it might have been a mix of a non-public constructor, letter casing and perhaps that I renamed the .jar to upper case by hand, not by eclipse.

  Thank you all for your help :)