Creating a loop for column & row constraints with JavaFX

Question

For my highscore window I have 20 nodes inside a gridpane (20 labels). Now I want the gridpane to be as big as the window itself which is 450 x 450, and I was planning to do this by adding column & row constraints.

This is what I tried, but got a NullPointerException.

private ColumnConstraints[] columnConstraintses;
private RowConstraints[] rowConstraintses;

for (int i = 0 ; i < 10 ; i++) {
        columnConstraintses[i] = new ColumnConstraints(40);
        rowConstraintses[i] = new RowConstraints(40);
    }

score 1 · Accepted Answer · answered Mar 09 '17 at 14:16

1

if you define an array you have to initiate it and set a size.

private ColumnConstraints[] columnConstraintses = new ColumnConstraints[10];
private RowConstraints[] rowConstraintses = RowConstraints[10];

answered Mar 09 '17 at 14:16

nano_nano

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Thanks! I completely forgot that I had to write = new ... []; , and thought the array was already created with default size. – m4t5k4 Mar 09 '17 at 14:22

score 1 · Answer 2 · answered Mar 09 '17 at 14:17

1

you did not initialize your arrays, try this:

private ColumnConstraints[] columnConstraintses = new ColumnConstraints[10];
private RowConstraints[] rowConstraintses = new RowConstraints[10];

answered Mar 09 '17 at 14:17

Maarten Blokker

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Creating a loop for column & row constraints with JavaFX

2 Answers2