How to remove all children components of a container?

Question

I have a swing application with a JPanel, which acts as a view port for my application. I want my application to remove all the components inside the view port when user clicks on a menu item or button and creates the new components inside it. I know how to remove a component from within a container, it is not clear which component is inside the view port currently, So I think I can't use below code:

viewport.remove(component);
viewport.revalidate();
viewport.repaint();

my questions:

1. How to remove all the components inside a container without knowing which component to remove?

2. Is this way of removing all the components and creating other components and inserting them to the view port correct?

Answer 1

The direct answer to your question is to simply call removeAll() on the container. The better answer though (since I think that your question is an example of an XY problem) is to use a CardLayout and simply swap components via this layout.