我们如何从 Javafx 的网格中返回一个按钮？

Question

I am trying to write a function that will return a button from the desired index of a GridPane. I am not getting the desired results. Here is my code

public Node getNodeFromGridPane(GridPane gridPane)
{
    int[] cord = new int[2];
    cord=getCord(count);
    int row=cord[0];
    int col=cord[1];
    System.out.println("Getting Label");
      for (Node node : gridPane.getChildren())
      {
        if (GridPane.getColumnIndex(node) == col && GridPane.getRowIndex(node) == row)
        {
            System.out.println("AAA");
          return node;
        }
      }
      return null;
}

Is there any other way to do this?

Answer 1

You are providing limited information. Why are you not getting the desired results?

I wrote the following code in Java, filling the gridpane with a few labels and one button.

  @Override
public void start(Stage primaryStage) throws Exception{
    primaryStage.setTitle("Hello World");
    GridPane gridPane = new GridPane();
    primaryStage.setScene(new Scene(gridPane, 300, 275));

    gridPane.setHgap(15);            // Improve readibility, can ignore
    gridPane.setVgap(15);            // Improve readibility, can ignore

    gridPane.add(new Label("c0r0"), 0,0);           // Add label on column 0, row 0
    gridPane.add(new Label("c0r1"), 0,1);           // Add label on column 0, row 1
    gridPane.add(new Label("c1r0"), 1, 0);          // Add label on column 1, row 0
    gridPane.add(new Label("c1r1"), 1,1);           // Add label on column 1, row 1
    gridPane.add(new Button("Button Test"), 2, 2);  // Add button on column 2, row 2

    int c, r;                                       // Column and row variable

    c=0; r=0;  // We want the Node on 0,0       
    System.out.println(((Label)findNodeByRowAndColumn(gridPane, c, r)).getText());
    c=0; r=1;  // We want the Node on 0,1
    System.out.println(((Label)findNodeByRowAndColumn(gridPane, c, r)).getText());
    c=1; r=0;  // We want the Node on 1,0
    System.out.println(((Label)findNodeByRowAndColumn(gridPane, c, r)).getText());
    c=1; r=1;  // We want the Node on 1,1
    System.out.println(((Label)findNodeByRowAndColumn(gridPane, c, r)).getText());
    c=2; r=2;  // We want the node on 2,2
    System.out.println(((Button)findNodeByRowAndColumn(gridPane, c, r)).getText());

    primaryStage.show();
}

public static Node findNodeByRowAndColumn(GridPane gridPane, int c, int r) {
    for(Node node : gridPane.getChildren()) {
        if (GridPane.getColumnIndex(node) == c && GridPane.getRowIndex(node) == r)
        {
            return node;
        }
    }
    return null;
}

What the GridPane looks like:

The programs output is:

c0r0 
c0r1
c1r0
c1r1
Button Test

This output is correct, based on the column and row indices which were passed.