Thread: Cardlayout Question

I am experimenting with Cardlayout and have hit a snag. I hope I can explain this so it is understandable.

I have three (for now) JPanels that are added to the Cardlayout and I can switch between them using menu items and buttons on the Toolbar of the JFrame. These JPanels are classes created using NetBeans GUI designer (each panel is a different Class). The contents of the Panels (cards) are set by the constructor of the Panel; for example a text field in the panel has the value set at time of panel construction.

MY QUESTION is how do I set values when a panel (card) is displayed? These panels will eventually be database record data entry & edit screens. So, when a card is displayed it will need to access a database and populate fields from the result set.

Can I create a method of the Panel that gets control when the Panel becomes active (top card, visible, etc.)? I tried adding a ComponentListener for when a panel is shown, but that didn't work (get control). Can I call a method of the Panel's Class in the button action that switches panels (cards)? If so, how? I can't seem to find the right code to access a public method of the Panel class from the Class of the main Frame.

Hope you understand what I'm asking and can help.
Thanks, Jim

There are many ways you could go about doing this. Load the data upon instantiation of the JPanels, load when you change the CardLayout (in an actionListener), add additional actionListeners to the buttons/menu items which fire a controller to load the data. The most straightforward approach would be just to load the data when you instantiate the JPanels, pass the data to each JPanel which is then responsible for placing the info in the correct place.