How to get x value from the last index in PVector ArrayList?

kevo1414

Hi fellows! :-h

I am trying to get in console x value from the last index in PVector ArrayList? VIDEO

ArrayList locations = new ArrayList();

void setup() {
  size(640, 360);
  locations.add( new PVector (width/2, height/2) );
  
}
void draw() {
  background(0);
  println(locations);
}

void mousePressed() {
  locations.add( new PVector (mouseX, mouseY) );
}

With this code above I am getting in console for each PVector x, y and z values. If I change println(locations); into println(locations.get(locations.size()-1)); I am getting only x,y and z values from the LAST PVector.

Now my question is how can I get from the last PVector x value?

This line of code println(locations.get(locations.x.size()-1)); gives me an error message "The global variable x does not exist."

GoToLoop

println( locations.get(locations.size() - 1).x );

https://Processing.org/reference/dot.html

kevo1414

Thanks for the reference, however this code

println( locations.get(locations.size() - 1).x );

gives me the same error as

println(locations.get(locations.x.size()-1));

"The global variable x does not exist."

"x cannot be resolved or is not a field"

VIDEO

koogs

your arraylist isn't typed, so the compiler doesn't know what it contains.

you can either define your arraylist as containing pvectors

ArrayList<PVector> locations = new ArrayList<PVector>();

or you can tell it what you've extracted at the point of extraction

PVector last = (PVector)locations.get(locations.size() - 1);
println(last.x);

the former is preferable.

kevo1414

Thank you.

GoToLoop

It's a good idea to 1st read the reference about the feature you're trying to use: ;)
https://Processing.org/reference/ArrayList.html

import java.util.List;
final List<PVector> locations = new ArrayList<PVector>();

locations.add( new PVector (width>>1, height>>1) );
println( locations.get(locations.size() - 1).x );

exit();