CODEWITHSUNDEEP
java
franvergara66
franvergara66

Reputation: 10784

Pass the name of a file to a void main, through a graphical interface in Java

i doing a program to calculate the critical path method from a DAG, program logic is perfect, but I have a problem trying to integrate a graphical user interface. The interface lets me through a JFileChooser to choose the input file for the program, but I do not know how to pass that parameter to the function "readfile", located in the main action.

Herés the code of the void main:

public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                JFrameConFondo jf = new EjemploJFrameConFondo();
                jf.setLocationRelativeTo(null);
                jf.setTitle("CPM");
                jf.setVisible(true);
                readfile(route);
               ////I need to pass a filename to the program which calculate the critical path,
            }
        });
    }
}

here's the code of the function "readfile":

public static void leer_archivo(String fileName){
        try{
       File archivo=new File(fileName);
       FileReader fr= new FileReader(archivo);
       BufferedReader br= new BufferedReader(fr);
       String linea;


       linea=br.readLine();
       c=Integer.parseInt(linea);
       for(int i=0;i<c;i++){
           CrearCaso(br, i+1);
       }
        }catch(Exception e){
        }
    }

I'm doing this action for the button on the interface for the file selection, and I want the name of that file in some way can be sent to void main to be able to use the function "readfile":

 private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton1ActionPerformed
         JFileChooser filechooser = new JFileChooser();
         int option = filechooser.showOpenDialog (this);
         if (option==JFileChooser.APPROVE_OPTION){
            cajaTexto.setText(filechooser.getSelectedFile().getPath());

        }

I hope someone can give me a hand with this, I'm stuck with this for a few days and I'm really new in the world Java. I did not put the whole code because there are several classes and several lines of code.

Upvotes: 1

Views: 143

Answers (2)

user1241335
user1241335

Reputation:

Ok, let me check if I understand your question properly...
You have a function readfile(String filename) that you want to call inside your main function.
You can get the path to the file using filechooser.getSelectedFile().getPath().
In this case you can export the selected path into a static variable of a public class.

So make a new class:

public class Globals
{
  private static String FilePath;
  public static String GetFilePath()
  {
    return FilePath;
  }
  public static void SetFilePath(String NewPath)
  {
    FilePath = NewPath;
  }
}

Set it with button using:

Globals.SetFilePath(filechooser.getSelectedFile().getPath());

And then use it so:

readfile(Globals.GetFilePath());

Notes*
This isn't necessarily the best solution available. It involves least changes to already exising source code though. Also, please excuse my Pascal notation, habit from C#.

Upvotes: 1

Moritz Petersen
Moritz Petersen

Reputation: 13057

You need to change your code in two places. I assume, that the button action is actually working. I assume, that your "main" class is called "MyProgram".

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton1ActionPerformed
     JFileChooser filechooser = new JFileChooser();
     int option = filechooser.showOpenDialog (this);
     if (option==JFileChooser.APPROVE_OPTION){
        String filename = filechooser.getSelectedFile().getPath();
        cajaTexto.setText(filename);
        // call main():
        MyProgram.main(new String[] { filename });
    }

public static void main(String args[]) {
            // assign file name
    final String route = args[0];
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                JFrameConFondo jf = new EjemploJFrameConFondo();
                jf.setLocationRelativeTo(null);
                jf.setTitle("CPM");
                jf.setVisible(true);
                readfile(route);
            }
        });
    }
}

Upvotes: 1

Related Questions