Processing PApplet call in nested classes - nested

Question

I'm using Processing 3 to make a GUI for a servo controller instead of using a pre-made library. It's based on having a packaging class organize several subclasses which use registerMethod mouse events to operate (as opposed to the simpler use of mousePressed() in the main sketch). What I'm getting hung up on is the PApplet naming/terms for each class to ensure that they can function both inside a subclass as well as on their own when called from the main. In my example the package is just a single button, as well as a direct button call for comparison. I do know that most current Java-users consider Applet use outdated, but since I'm just using the Processing IDE, I'd like to understand this concept better as well as try to avoid using something more complicated (but maybe less confusing) like an Interface.
PackServ tryMe;
Butt bOne;
void setup() {
size(200, 150);
tryMe = new PackServ(this);
bOne = new Butt(this);
}
void draw() {
background (250);
tryMe.Add(20, 10, 50);
line(100,10,100,100);
fill(130,255,170);
rect(120,10,50,60,5);
bOne.Add("B2", 145,35,25);
stroke(20); textSize(14); fill(25);
text("single", 130,100);
text("package", 20,100);
}
public class PackServ extends PApplet {
PApplet SerApp;
Butt Butt1, Butt2;
String theName;
int pkX, pkY, pkW;
PackServ(PApplet pa) {
this.SerApp = pa;
theName = "The Slider";
pkX = 20;
pkY = 20;
pkW = 100;
}
void Add(int _x, int _y, int _w) {
pkX = _x; pkY = _y; pkW = _w;
Butt1 = new Butt (this);
drawIt();
}
void drawIt() {
SerApp.fill(200);
SerApp.strokeWeight(1);
SerApp.rect(pkX, pkY, pkW, 60, 5);
Butt1.Add("B1", pkX+25, pkY+25, 25);
}
}
public class Butt
{
PApplet butApp;
int theX, theY, theW, theH, bRad;
boolean pressed = false;
color n;
color h = color(240, 210, 10);
color f = color (40, 90, 190);
color a = color (240, 20, 20);
int oBb, li;
String theLabel;
Butt (PApplet butApplet) {
this.butApp = butApplet;
butApp.registerMethod("mouseEvent",this);
n = f;
}
void Add(String _myName, int x, int y, int siz) {
theLabel = _myName;
theX = x;
theY = y;
bRad = siz;
fill(75);
textSize(9);
buttonLook();
}
boolean overB(int mx, int my) {
if (dist (mx, my, theX, theY) <= bRad) {
return true;
} else {
return false;
}
}
void buttonLook() {
if (overB(mouseX, mouseY) && pressed) {
n = a;
oBb = 3; li = 100;
} else if (overB(mouseX, mouseY)) {
text(theLabel, theX-10, theY+25);
n = h;
} else {
n = f; oBb=1; li=25;
}
strokeWeight(oBb);
stroke(li);
fill(n);
ellipse(theX, theY, bRad, bRad);
}
void mouseEvent(MouseEvent e) {
pressed = false;
int mx = e.getX(), my = e.getY();
switch (e.getAction()) {
case MouseEvent.PRESS:
pressed = overB(mx, my);
break;
}
}
}

Answer 1

I'm not totally sure what you're asking, so let me try to answer a few different things that you seem a bit confused about.
I do know that most current Java-users consider Applet use outdated
Please note that other than its name, PApplet has nothing to do with applets. Historically a PApplet was an applet, but as of Processing 3 that's no longer the case. PApplet is its own thing and has nothing to do with applets.
Let's take a closer look at this code:
public class PackServ extends PApplet {
PApplet SerApp;
PackServ(PApplet pa) {
this.SerApp = pa;
...
It doesn't make a ton of sense to extend PApplet and also take a PApplet argument into the constructor. This means that you now have two PApplet instances, which is almost never what you want to do.
Instead, my guess is you probably want to get rid of the extends PApplet part and only use Processing's classes using your serApp variable.
I believe that's the crux of your confusion: the PApplet class offers a bunch of handy functions like draw() and ellipse(), basically most variables and functions in the Processing reference. So you do need an instance of PApplet, but that instance is created for you when you use the Processing editor. You don't need to create your own instance by extending the PApplet class.