How do I add a margin outside the border of a component in Swing?

问题

I use multiple components that has a border painted. Is there any easy way to add a margin to the component so that the borders aren't painted so close to eachother?

回答1:

This is typically done using your layout manager. For example, if you are using GridBagLayout, you would set insets on the GridBagConstraint object to the desired value.

Another option is to use the Box object and add a horizontal or vertical struct. See javadoc for Box.createVerticalStrut( int width ) and the similar createHorizontalStrut.

回答2:

Another way to get what you want is to:

get the current Border of your component
if null, set an EmptyBorder for your component
if not null, create a new CompoundBorder (with an EmptyBorder and the current Border of the component) and set it for the component

In code, that should look like that (sorry I haven't tested it):

Border current = component.getBorder();
Border empty = new EmptyBorder(top, left, bottom right);
if (current == null)
{
    component.setBorder(empty);
}
else
{
    component.setBorder(new CompoundBorder(empty, current));
}

Where:

component is the Swing component to which you want to add a margin
top, left, bottom, right are the pixels amounts you want to add around your component

Note that this method might have an impact (size, alignment) on the form layout, depending on the LayoutManager you are using. But I think it is worth trying.

来源：https://stackoverflow.com/questions/2883291/how-do-i-add-a-margin-outside-the-border-of-a-component-in-swing

标签

java

swing

border

margin