Modifying a text file in Android

[a_random_cat]

HI. Im making an app to control some LEDs, and it works with bluetooth so it needs to be able to allow the user to change the MAC direction of the controller. the thing is that there are 2 problems; When Converting the String lines into a normal string with .toString(); it returns something like this: [Ljava.lang.String;@1b4163d. And the second problem, when I write saveStrings(“mac.txt”, lines);, it doesnt change anything. here is the code:

PImage img1;
PImage img2;
PImage img3;
PImage img4;
PImage img5;
PImage img6;
PImage img7;
PImage img8;
PImage img9;
PImage img10;
PImage img11;
String typing = "";
String saved = "";
boolean sett = false;
import java.io.File;
int si = 0;
int igri = 0;
String elstr="";
boolean keyboard = false;
boolean interm = false;
boolean error = false;
import ketai.net.bluetooth.*;
import android.os.Bundle;
String device_name = "ESP32";
String device_mac = "";
KetaiBluetooth bt;
void setup() {
  String[] lines = loadStrings("mac.txt");
  device_mac = lines.toString();
  img1 = loadImage("img1.png");
  img2 = loadImage("img2.png");
  img3 = loadImage("img3.png");
  img4 = loadImage("img4.png");
  img5 = loadImage("img5.png");
  img6 = loadImage("img6.png");
  img7 = loadImage("img7.png");
  img8 = loadImage("img8.png");
  img9 = loadImage("img9.png");
  img10 = loadImage("img10.png");
  img11 = loadImage("img11.png");
  fullScreen();
  orientation(LANDSCAPE); 
  noStroke();
  fill(0);
  bt = new KetaiBluetooth(this);
  bt.getPairedDeviceNames();
  bt.start();
  bt.connectToDeviceByName(device_name);
  String awewo = lines.toString();
  boolean porque = awewo.contains(":");
  print(lines);
  print(porque);
  print(awewo);
}
/*String str = "igri";
      byte[] data = str.getBytes();
      bt.writeToDeviceName(device_name, data);
      delay(1000);
      background(255,0,0);
      image(led1, 670, 100,130,100);
*/

void draw(){
  if(!sett){
  drawmenu();}
  else{setting();}
  int indent = 25;
  if(mousePressed){
  si = mouseX;
  igri = mouseY;
  print(si," ",igri);
  matense(si,igri);
}
  }
void drawmenu(){
  if(error){
    background(255,0,0);
    text("No hay una direccion MAC puesta!",100,300);
    setting();
  }
  else{
  fill(255,255,255);
  background(75,59,59);
  textSize(60);
text("Control", 70, 70);
text("Paleta de colores", 500, 70);
text("Extras", 1200, 70);
  image(img1,100,80,130,130);
  image(img2,100,230,130,130);
  if(interm){
    image(img7,100,370,130,130);
  image(img8,100,510,130,130);
  }
  else{
  image(img3,100,370,130,130);
  image(img4,100,510,130,130);
  }
  image(img5,1200,80,130,130);
  image(img6,1200,230,130,130);
  image(img9,1200,370,130,130);
  image(img10,1200,510,130,130);
  image(img11,1400,30,100,100);
  fill(255,0,0);
  rect(350,80,130,130);
  fill(0,255,0);
  rect(350,230,130,130);
  fill(0,0,255);
  rect(350,370,130,130);
  fill(255,255,255);
  rect(350,510,130,130);
  //a
  fill(247,105,10);
  rect(490,80,130,130);
  fill(31,240,81);
  rect(490,230,130,130);
  fill(31,85,240);
  rect(490,370,130,130);

  //b
  fill(240,167,31);
  rect(630,80,130,130);
  fill(31,172,240);
  rect(630,230,130,130);
  fill(165,23,116);
  rect(630,370,130,130);
  //c
  fill(255,175,0);
  rect(775,80,130,130);
  fill(8,188,206);
  rect(775,230,130,130);
  fill(232,12,133);
  rect(775,370,130,130);

  //d
  fill(234,255,15);
  rect(915,80,130,130);
  fill(9,107,180);
  rect(915,230,130,130);
  fill(255,3,167);
  rect(915,370,130,130);
}
}

void matense(int x, int y){
  String str = "";
  if(x>=100 && x<=230){
  if(y>=80 && y<=220){str="a";}
  if(y>=230 && y<=360){str="b";}
  if(y>=370 && y<=500){if(interm){str="5";}else{str="c";}}
  if(y>=510 && y<=640){if(interm){str="7";}else{str="d";}}
}
  if(x>=490 && x<=620){
    interm = false;
  if(y>=80 && y<=220){str="e";}
  if(y>=230 && y<=360){str="f";}
  if(y>=370 && y<=500){str="g";}
  if(y>=510 && y<=640){str="h";}
}
  if(x>=630 && x<=760){
    interm = false;
  if(y>=80 && y<=220){str="i";}
  if(y>=230 && y<=360){str="j";}
  if(y>=370 && y<=500){str="k";}
  if(y>=510 && y<=640){str="l";}
}
  if(x>=775 && x<=905){
    interm = false;
  if(y>=80 && y<=220){str="m";}
  if(y>=230 && y<=360){str="n";}
  if(y>=370 && y<=500){str="o";}
  if(y>=510 && y<=640){str="p";}
}
  if(x>=915 && x<=1045){
    interm = false;
  if(y>=80 && y<=220){str="q";}
  if(y>=230 && y<=360){str="r";}
  if(y>=370 && y<=500){str="s";}
  if(y>=510 && y<=640){str="t";}
}
  if(x>=350 && x<=480){
    interm = false;
  if(y>=80 && y<=220){str="v";}
  if(y>=230 && y<=360){str="w";}
  if(y>=370 && y<=500){str="x";}
  if(y>=510 && y<=640){str="y";}
}
  if(x>=1200 && x<=1330){
    interm = true;
  if(y>=80 && y<=220){str="2";}
  if(y>=230 && y<=360){str="3";}
  if(y>=370 && y<=500){str="4";}
  if(y>=510 && y<=640){str="8";}
}
if(x>=1400 && x<=1500){
if(y>=30 && y<=130){
  sett = true;
}}
print(str);

      byte[] data = str.getBytes();
      bt.writeToDeviceName(device_name, data);
      delay(100);
}
void setting(){
  int indent = 25;
  fill(0,0,255);
  rect(230,80,815,560);
  fill(255,255,255);
  fill(255,255,0);
  rect(250,200,50,50);
  fill(0,255,0);
  rect(250,150,50,50);
  fill(255,0,0);
  rect(995,150,50,50);
  text("Configuracion",230,140);
  textSize(40);
  fill(0,255,0);
  text("Introduce la nueva Direccion MAC en \n minuscula para conectarse al ESP32. \n La MAC puede ser vista en el \n menu de la pantalla en 'CON' ",230,470);
  textSize(60);
  fill(255,255,255);
  text("Atras",900,600);
  text("Nueva mac: "+ saved,230,400);
  text("<-- Abrir teclado",300,250);
  text("<-- Borrar          Guardar -->",300,200);
  textSize(60);
  text("MAC:" + typing,230,300);
    if(mousePressed){
  si = mouseX;
  igri = mouseY;
}
if(mouseX >= 995 && mouseX <= 1040 && mouseY >= 150 && mouseY <= 200){
  String[] lines = loadStrings("mac.txt");
if(lines.length>1)
  lines[1] = saved;
  saveStrings("mac.txt", lines);
  print("Guardado: "+saved);
}
if (mouseX >= 250 && mouseX <= 300){
  if(mouseY >= 200 && mouseY <= 250){
    if (!keyboard) {
    openKeyboard();
    keyboard = true;   
  }
  }
  if(mouseY >= 150 && mouseY <= 200){
    typing = "";
    saved = "";
    mouseY = mouseY + 100;
  }
}
else {
    closeKeyboard();
    keyboard = false;
  }
if(si>=900&&si<=1045){
  if(igri>=580&&igri<=600){
    sett=false;
  }
}

}

void keyPressed() {
  // If the return key is pressed, save the String and clear it
  if (key == '\n' ) {
    String my_new_str = typing.replace(",", ":");
    saved = my_new_str;
    // A String can be cleared by setting it equal to ""
    typing = ""; 
  } else {
    // Otherwise, concatenate the String
    // Each character typed by the user is added to the end of the String variable.
    typing = typing + key; 
  }
}

[jafal]

Hi

Make simple sketch to make sure that you can save and load from folder

[mnse]

Hi @a_random_cat,

This shows the string representation of your array (What!?) …

@a_random_cat

String awewo = lines.toString();

Use this:

join() / Reference

Cheers
— mnse

PS: do it like @jafal suggested. Write small code to test the single steps…
PPS: And think about refactoring your code …

Code refactoring

[glv]

Hello @a_random_cat,

This will help us help you:

Guidelines—Asking Questions

Summary (TL;DR) Ask complete questions to get better answers! Be specific. For example: I want to load an image. I tried using createImg() , and I expected the image to be on canvas, but what happened instead was the image showing up below the canvas. Isolate your problem and work in small steps. Share only the code directly related to your problem if it is part of a bigger project, and if something isn’t working, try the smallest code that could do the thing you want. Can we run your code …

Working example to extract string from array:

String [] lines = loadStrings("mac.txt");

printArray(lines);
println();

String awewo = lines[0].toString();
println(awewo);

println();

mac.txt file contents:

aa:bb:cc:dd:ee
https://www.processing.org
https://discourse.processing.org/t/guidelines-asking-questions/2147
https://stackoverflow.com/help/minimal-reproducible-example
500.7
12

Console output on Processing JAVA:

References:
https://processing.org/reference/loadStrings_.html
https://stackoverflow.com/help/minimal-reproducible-example < This is in the Guidelines

:)

[a_random_cat]

As you suggested, I write a simple code to check that I could save files.

void setup(){
  String[] lines = loadStrings("mac.txt");
  print(lines[0]);
  String words = "jenfokhugihrufgtr";
String[] list = split(words, ' ');

// Writes the strings to a file, each on a separate line
saveStrings("mac.txt", list);
String[] non = loadStrings("mac.txt");
  print(non[0]);
}
void draw(){
}

I executed it in java and it worked, but I executed it in android and it didn’t work. Maybe the “data” folder is only read?

[a_random_cat]

I just did a small research and, yes, the data folder is only read, so is there a way to use the normal phone storage to save my text file there?