Question

I am very new to Swing, and I’m trying to make a GUI.
Using Netbeans’ GUI creator thing, I managed to make something I liked. But it makes me feel bad that I used the editor for this, so now I am trying to make the same design using code.
Here is a picture of what I am trying to make:

Right now I am just focusing on creating the “Criteria” section (yes I know I spelled it wrong in the picture)
Here is what I currently have so far:

I’ve highlighted in red where I want to increase the margin:

• Between the right of the text boxes and left of the labels
• Between the top of the Criteria panel and the JFrame
• Between the left and right sides of the panel and the JFrame

I come from web development where increasing the margins is what I want to do. If this is incorrect terminology, please inform me.
Here is the code I am currently using:

public class Criteria extends JPanel {
    JLabel JobLabel = new JLabel();
    JLabel BoxLabel = new JLabel();
    JLabel PartLabel = new JLabel();
    JTextField JobInput = new JTextField();
    JTextField BoxInput = new JTextField();
    JTextField PartInput = new JTextField();

    public Criteria() {
        setLayout(new FlowLayout(FlowLayout.LEADING));
        setBorder(BorderFactory.createTitledBorder("Criteria"));
        JobLabel.setText("Job");
        JobLabel.setLabelFor(JobInput);
        BoxLabel.setText("Box");
        BoxLabel.setLabelFor(BoxInput);
        PartLabel.setText("Part");
        PartLabel.setLabelFor(PartInput);
        JobInput.setColumns(8);
        BoxInput.setColumns(8);
        PartInput.setColumns(8);
        add(JobLabel);
        add(JobInput);
        add(BoxLabel);
        add(BoxInput);
        add(PartLabel);
        add(PartInput);
    }
}

I don’t know how I would add margin to these components, so help would be very much appreciated. If I cannot achieve this effect with FlowLayout, then please tell me what I should use instead.

Answer 1

Swing tends to call margins or borders ‘gaps’. The FlowLayout class (along with a few other layout classes) allows you to set the horizontal and vertical gaps in its constructor, like so:

private static final int PADDING = 3;   // for example
...
    setLayout(new FlowLayout(FlowLayout.LEADING, PADDING, PADDING));

This would add padding between the labels and their text boxes, however, but you could wrap each pair in a JPanel (probably with a FlowLayout). I would make a custom component class for this.