Resize TabPane on runtime (JavaFX8)

Question

I have a window that looks like this:

What I want, is when user selects specific item from combobox at the bottom, additional labels and textfields appears between buttons and bottom textfield , so it will look something like this:

For this I'm using an additional grid pane with height=0:

And when I simply add rows to that grid from builder, tabPane is being resized automatically and I get what I need as it shown on second picture. But when I'm trying to do it in code, like this:

            ColumnConstraints col1 = new ColumnConstraints();
            ColumnConstraints col2 = new ColumnConstraints();
            ColumnConstraints col3 = new ColumnConstraints();
            ColumnConstraints col4 = new ColumnConstraints();
            ColumnConstraints col5 = new ColumnConstraints();
            ColumnConstraints col6 = new ColumnConstraints();

            myGrid.getColumnConstraints().addAll(col1,col2,col3,col4,col5,col6);

            myGrid.add(new Label("Label"), 0, 0);
            myGrid.add(new Label("Label"), 0, 1);
            myGrid.add(new Label("Label"), 0, 2);
            myGrid.add(new Label("Label"), 0, 3);
            myGrid.add(new Label("Label"), 0, 4);
            myGrid.add(new Label("Label"), 0, 5);

            myGrid.add(new TextField(), 1, 0);
            myGrid.add(new TextField(), 1, 1);
            myGrid.add(new TextField(), 1, 2);
            myGrid.add(new TextField(), 1, 3);
            myGrid.add(new TextField(), 1, 4);
            myGrid.add(new TextField(), 1, 5);

• In here myGrid - is that gridpane with height=0 at the begginin. And I'm having such screen, with tabpane not re-sized:

What am I doing wrong? Could someone explain please?

BTW - on all other elements like HBox and other everywhere pref Height = USE_COMPUTED_SIZE

Answer 1

What have you tried so far?

I believe calling myGrid.autosize(); after adding all children should solve your problem.

Answer 2

Well, for me as a solution ("dirty" solution) worked this:

// Height set manually
tabPane.getScene().getWindow().setHeight(700);

If someone knows how to set it's height dynamically (depending on GridPane height), please, respond.