Agfdhyk

I am trying to get my list of images to display on a 5x5 grid. I cannot figure out what the issue is.

This is the assignment instructions:
Assignment:

Create image BINGO. Using the exercise 14.1 page 586 as a foundation: Write a program that randomly displays images on a Bingo card. This should be a 5X5 grid with the letters B I N G O across the top.

//package

package javafxapplication2;

//import

import javafx.application.Application;

import javafx.geometry.HPos;

import javafx.geometry.Pos;

import javafx.geometry.VPos;

import javafx.scene.Scene;

import javafx.scene.control.TextField;

import javafx.scene.layout.GridPane;

import javafx.stage.Stage;

import javafx.scene.image.ImageView;

import javafx.scene.image.Image;



/**

 *

 * @author travis.dutton

 */

public class JavaFXApplication2 extends Application {

  @Override // Override the start method in the Application class

  public void start(Stage primaryStage) {



    GridPane pane = new GridPane();

    pane.setAlignment(Pos.CENTER);

    pane.setHgap(5);

    pane.setVgap(5);



    ImageView flags;

    flags = new ImageView[25];



    flags[0] = new ImageView("images/1.png");

    flags[1] = new ImageView("images/2.jpg");

    flags[2] = new ImageView("images/3.gif");

    flags[3] = new ImageView("images/4.gif");

    flags[4] = new ImageView("images/5.jpg");

    flags[5] = new ImageView("images/6.png");

    flags[6] = new ImageView("images/7.gif");

    flags[7] = new ImageView("images/8.jpg");

    flags[8] = new ImageView("images/9.png");

    flags[9] = new ImageView("images/10.png");

    flags[10] = new ImageView("images/11.jpg");

    flags[11] = new ImageView("images/12.png");

    flags[12] = new ImageView("images/13.png");

    flags[13] = new ImageView("images/14.png");

    flags[14] = new ImageView("images/15.png");

    flags[15] = new ImageView("images/16.png");

    flags[16] = new ImageView("images/17.gif");

    flags[17] = new ImageView("images/18.gif");

    flags[18] = new ImageView("images/19.png");

    flags[19] = new ImageView("images/20.jpg");

    flags[20] = new ImageView("images/21.png");

    flags[21] = new ImageView("images/22.png");

    flags[22] = new ImageView("images/23.png");

//    flags[23] = new ImageView("images/24.gif");

//    flags[24] = new ImageView("images/25.png");



//    pane.add(flags[0], 0, 0);

//    pane.add(imageView2, 1, 0);

//    pane.add(imageView3, 0, 1);

//    pane.add(imageView4, 1, 1);



//  for(int i = 0; i < flags.length; i++){

//       

//       GridPane.setRowIndex(flags[i],1);

//       GridPane.setColumnIndex(flags[i],i);

//       pane.getChildren().add(flags[i]);

//    }



    for(int i = 0; i < 5; i++){

        for (int j = 0; j < 5; j++) {

            ImageView image = new ImageView();

            image.setColumnIndex(1);

            image.getChildren(String.valueOf(flags));

            pane.add(image, i, j);



        }

    }









       // Create a scene and place it in the stage

    Scene scene = new Scene(pane);

    primaryStage.setTitle("Exercise14_01"); // Set the stage title

    primaryStage.setScene(scene); // Place the scene in the stage

    primaryStage.show(); // Display the stage

  }







  /**

   * The main method is only needed for the IDE with limited

   * JavaFX support. Not needed for running from the command line.

   */

  public static void main(String args) {

    launch(args);//launch javafx

  }//end main

}//end of class

ImageView does not provide a getChildren method. (I don't know a JavaFX class that provides one that takes a String parameter btw). ImageViews are nodes and should be placed in the GridPane directly using the GridPane.add(Node, int, int) method.

You can use Collections.shuffle to generate the premutation:

String images = new String {

    "images/1.png",

    "images/2.jpg",

    ...

    "images/25.png"

};



// using a list with indices here to keep the original index order intact.

// (You could use a list of String and shuffle it otherwise)

List<Integer> permutation = IntStream.range(0, images.length).boxed().collect(Collectors.toCollection(ArrayList::new));

Collections.shuffle(permutation);



for(int i = 0, index = 0; i < 5; i++){

    for (int j = 1; j <= 5; j++) {

        ImageView image = new ImageView(images[permutation.get(index)]);

        pane.add(image, i, j);

        index++;

    }

}



// bingo accross the top (not sure if this is what was asked for)

pane.add(new Label("Bingo"), 0, 0, 5, 1);

If you want put random images to GridPane, like:

you have to do something like this:

    final ArrayList<ImageView> flags = new ArrayList<>();



    flags.add(new ImageView("images/1.png"));

    flags.add(new ImageView("images/2.png"));

    flags.add(new ImageView("images/3.png"));

    // add flags



     for (int columnIndex = 0; columnIndex < 5; i++) {

        for (int rowIndex = 0; rowIndex < 5; j++) {

            if(isNotBingoCell(columnIndex, rowIndex)) { //check that cell is not BINGO cell

                final int imageIndex = Objects.equals(flags.size(), 1)

                        ? 0

                        : ThreadLocalRandom.current().nextInt(0, flags.size() - 1);

                pane.add(flags.get(imageIndex), columnIndex, rowIndex);

                flags.remove(imageIndex);

                flags.trimToSize();

            }

        }

    }

, isNotBingoCell(...) implemintation:

    private boolean isNotBingoCell(int columnIndex, int rowIndex) {

        return !Objects.equals(columnIndex, rowIndex);

    }