我创建了100个文本字段并将它们放入gridPane中。用户可以更改任何文本字段中的值。我需要能够注册该更改的值，以便我的按钮找到最大尺寸子方块将正常工作。因为文本字段是在循环中创建的，所以我不知道如何在任何单个文本字段中监听更改。
import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Paint;
import javafx.stage.Stage;
import static java.lang.Math.rint;
public class Exercise22_19 extends Application {
//declare a gridpane here so that methods have easy access
GridPane gp1;
int[][] valList;
@Override
public void start(Stage primaryStage) {
//stack pane to hold the gridpane; makes it easy to keep the grid
//centered in the stage
StackPane root = new StackPane();
///gridpane to hold the 10x10 matrix of textfields
gp1 = new GridPane();
gp1.setPadding(new Insets(5, 5, 5, 5));
//center the gridpane in the stackpane
gp1.setAlignment(Pos.CENTER);
root.getChildren().add(gp1);
setNumbers();
//refresh button: refills matrix with new values
Button refreshBt = new Button("Refresh");
//call the function to reset the values in the matrix when the refresh
//button is clicked
refreshBt.setOnAction(e -> setNumbers());
//findLargestBlock button finds the largest square block of 1's in the
//matrix
Button lrgBlkBt = new Button("Find Largest Button");
//call the function to find the largest square block of 1's when the
//find button is clicked
lrgBlkBt.setOnAction(e -> findBigBlock());
//makes a space between the last row of numbers and the buttons. Even
//though it is onle set on one button, it affects the entire row
GridPane.setMargin(refreshBt, new Insets(5, 5, 5, 5));
//add buttons to gridpane
//refresh spans 3 columns
gp1.add(refreshBt, 1, 10, 3, 1);
//find spans 6 columns
gp1.add(lrgBlkBt, 4, 10, 6, 1);
Scene scene = new Scene(root);
primaryStage.setTitle("Exercise 22_19 (Dynamic)");
primaryStage.setScene(scene);
primaryStage.show();
}
//set all textfield values in the matrix to 0 or 1
public void setNumbers() {
//gridpane does not have a method to access the value of a node in the
//gridpane, so I will store the values in an array.
valList = new int[10][10];
for (int i = 0; i < 10; i++) {
for (int k = 0; k < 10; k++) {
TextField tf = new TextField();
tf.setPrefWidth(25);
//set the value of the text field to 0 or 1
//create a random 0 or 1 integer
int val = (int)(rint(Math.random()));
//fill the array with the values
valList[i][k] = val;
String valStr = String.valueOf(val);
tf.setText(valStr);
//add text fields to gridpane
GridPane.setConstraints(tf, k, i);
gp1.getChildren().add(tf);
}
}
}
//find the largest square block of 1's in the matrix
public void findBigBlock() {
//size of square matrix
int n = 10;
//max tells the size of the largest square sub-maxtrix, e.g. if max==3,
//the largest sub-matrix is a 3x3 matrix
int max = 0;
int maxRow = 0;
int maxCol = 0;
//color for the textbox; red
Paint tfColor = Paint.valueOf("FF0000");
int[][] arr = new int[10][10];
//copy first row to new array
System.arraycopy(valList[0], 0, arr[0], 0, 10);
//copy first col to new array
for (int i = 0; i < n; i++) {
arr[i][0] = valList[i][0];
}
//determines the size and location of the maximum sub-square
for (int row = 1; row < n; row++) {
for (int col = 1; col < n; col++) {
if (valList[row][col] == 1) {
arr[row][col] =((Math.min(valList[row][col-1],
(Math.min(valList[row-1][col], valList[row-1][col-1])))) + 1);
if (arr[row][col] >= max) {
max = arr[row][col];
maxRow = row;
maxCol = col;
}
}
else
arr[row][col] = 0;
}
}
//replaces the normal textfields with red textfields for the maximum
//sub-square
for (int i = max; i > 0; i--) {
for (int j = maxRow; j > maxRow - max; j--) {
for (int k = maxCol; k > maxCol - max; k--) {
//create a nex textfield
TextField tf = new TextField();
tf.setPrefWidth(25);
//set color to red
tf.setStyle("-fx-control-inner-background: #"+tfColor.toString().substring(2));
tf.setText(String.valueOf(valList[j][k]));
//put the red textfield into the gridpane
GridPane.setConstraints(tf, k, j);
gp1.getChildren().add(tf);
}
}
}
}
public static void main(String[] args) {
Application.launch(args);
}
}
答案 0 :(得分：1)
这样的事情会适用于你的情况：
public void setNumbers() {
//gridpane does not have a method to access the value of a node in the
//gridpane, so I will store the values in an array.
valList = new int[10][10];
for (int i = 0; i < 10; i++) {
for (int k = 0; k < 10; k++) {
TextField tf = new TextField();
tf.setPrefWidth(25);
//set the value of the text field to 0 or 1
//create a random 0 or 1 integer
int val = (int)(rint(Math.random()));
//fill the array with the values
valList[i][k] = val;
String valStr = String.valueOf(val);
tf.setText(valStr);
//add text fields to gridpane
GridPane.setConstraints(tf, k, i);
gp1.getChildren().add(tf);
tf.textProperty().addListener((observable, oldValue, newValue) -> {
valList[GridPane.getRowIndex(tf)][GridPane.getColumnIndex(tf)] = Integer.parseInt(newValue);
});
}
}
}
请注意，您应该为so
等字段添加类型检查