setBorder on JTextField does not work ? or does it?

问题

The code is like this:

JTextField txt = new JTextField();
txt.setBorder(BorderFactory.createMatteBorder(2,2,2,2,Color.red));

However the text field is ignoring my call to setBorder. No changes whatsoever.

I were to replace it with a JLabel (for instance)

JLabel txt = new JLabel();
txt.setBorder(BorderFactory.createMatteBorder(2,2,2,2,Color.red));

I would see the red border.

Can anybody tell me why? Or even better explain to me how to add a border in the JTextField?

回答1:

Check out this explanation/recommendation from the Java API

In general, when you want to set a border on a standard Swing component other than JPanel or JLabel, we recommend that you put the component in a JPanel and set the border on the JPanel.

So... you should nest your JTextField in a JPanel or JLabel, and put the border on the JPanel or JLabel. Voila!

来源：https://stackoverflow.com/questions/2281539/setborder-on-jtextfield-does-not-work-or-does-it