Java：如何将动态数量的参数传递给方法

Question

I am writing a JavaFX app and I need to add n amount of TextField objects to a row in a GridPane using its addRow method. addRow accepts any number of arguments, but the amount of of TextField objects it receives is not hard coded. For example,

GridPane gp = new GridPane();
ArrayList<TextField> tf = new ArrayList<>();
for (int i = 0; i < user_entered_number; i++) {
    tf.add(new TextField());
}
gp.addRow(row_index, /* all elements in tf*/);

I wish to include all generated TextField objects in the GridPane row at row_index using the allRow method.

If this is even possible, how can I do it?

Answer 1

The GridPane.addRow(...) method takes an int (the row index) and a varargs of Node s. You can pass an array for a varargs parameter, so you can do

gp.addRow(row_index, tf.toArray(new Node[0]));

Alternatively, just create an array instead of a list in the first place:

GridPane gp = new GridPane();
TextField[] tf = new TextField[userEnteredNumber];
for (int i = 0; i < userEnteredNumber; i++) {
    tf[i] = new TextField();
}
gp.addRow(row_index, tf);

Answer 2

I am not sure if I understand your problem properly. Do you want to add all the elements from tf ArrayList as arguments in addRow() method?

addRow() mathod takes varargs as an argument. Did you try convert the ArrayList into array and then pass it to the method?

TextField[] arr = new TextField[tf.size()];
arr = tf.toArray(arr);