问题
I am creating am application that displays circles (of different colors) randomly within each cell of a gridPane.
What i want to do is create a "shuffle" button that changes the position of each circle randomly within the gridPane. However, I keep running into a slurry of problems.
Here is what i have so far. My two classes (have not added XML file):
Controller Class
public class viewController {
//My two Variables, a gridPane and a button
@FXML
private GridPane matrix;
@FXML
private Button shuffleBut;
//my eventHandler event that should (1) add circles to all the cells, and
(2) shuffle them amongst the cells in the gridPane.
void shuffle(ActionEvent e) {
Random r = new Random ();
int rowShuffle = r.next((4-0)+1);
int colShuffle = r.next((4-0)+1);
Circle newCircle = new Circle ();
matrix.add(newCircle, rowShuffle, colShuffle );
}
Main Class
public class Main extends Application {
@Override
public void start(Stage primaryStage) throws Exception {
// just load fxml file and display it in the stage:
Parent root = FXMLLoader.Load(getClass().getResource("mainUI.fxml"));
Scene scene = new Scene(root);
primaryStage.setScene(scene);
primaryStage.show();
}
// main method to support non-JavaFX-aware environments:
public static void main(String[] args) {
// starts the FX toolkit, instantiates this class,
// and calls start(...) on the FX Application thread:
launch(args);
}
回答1:
Here is an example that demos how to shuffle Circles
around in a GridPane
. If you add the Circles
to an ArrayList
, you can remove the Circles
from the GridPane
. Then you can shuffle the List
. Finally, you can add the shuffled list back to the GridPane
.
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Random;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Control;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;
/**
*
* @author blj0011
*/
public class JavaFXApplication314 extends Application
{
Random random = new Random();
int numberOfRows = 25;
int numberOfColumns = 25;
@Override
public void start(Stage primaryStage)
{
List<Circle> circles = new ArrayList();
for (int i = 0; i < numberOfColumns * numberOfRows; i++) {
circles.add(new Circle(10, getRandomColor()));
}
GridPane gridPane = new GridPane();
addCirclesToGridPane(gridPane, circles);
gridPane.setPadding(new Insets(20, 20, 20, 20));
Button btn = new Button();
btn.setText("Say 'Hello World'");
btn.setOnAction((ActionEvent event) -> {
Collections.shuffle(circles);//Shuffle the List of Circles.
for(int i = 0; i < numberOfColumns * numberOfRows; i++)
{
Circle c = circles.get(i);
GridPane.setColumnIndex(c, i % numberOfColumns);
GridPane.setRowIndex(c, i / numberOfColumns);
}
});
VBox vBox = new VBox(gridPane, new StackPane(btn));
vBox.setMaxSize(Control.USE_COMPUTED_SIZE, Control.USE_COMPUTED_SIZE);
StackPane root = new StackPane(vBox);
root.setMaxSize(Double.MAX_VALUE, Double.MAX_VALUE);
Scene scene = new Scene(root);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args)
{
launch(args);
}
public void addCirclesToGridPane(GridPane gridPane, List<Circle> circles)
{
for (int i = 0; i < numberOfColumns * numberOfRows; i++) {
gridPane.add(circles.get(i), i % numberOfColumns, i / numberOfColumns);
}
}
public Color getRandomColor()
{
int r = random.nextInt(255);
int g = random.nextInt(255);
int b = random.nextInt(255);
return Color.rgb(r, g, b);
}
}
来源:https://stackoverflow.com/questions/53708509/randomly-displaying-circles-within-gridpane-cells-in-javafx