The default layout of a JFrame (or more specifically in this case, the content pane of the frame) is a BorderLayout. When adding a component to a BordeLayout with no constraint, the Swing API will put the component in the CENTER. A BorderLayout can contain exactly one component in each of the 5 layout constraints. … Read more
Your use case, seems perfect for CardLayout. In card layout you can add multiple panels in the same place, but then show or hide, one panel at a time.
How to Use CardLayout With a new JFrame form, add a JPanel, a few JButtons to the form so it looks like this Your navigator pane should look like this. Notice I changed the variable names. You can do that by right clicking on the component from the navigator and selecting change variable name. Now … Read more
The content pane of a JFrame has a BorderLayout. If you place a component in a BL with no constraints it ends up in the CENTER. The center can only display one component. For an immediate effect, I suggest: f.add(top, BorderLayout.PAGE_START); f.add(mid); f.add(bot, BorderLayout.PAGE_END); Other points. Take out f.setSize(500, 500); and call pack() immediately before … Read more
Notes The chess board complete with columns on the left and above it is provided by a 9×9 GridLayout. The first cell of the grid layout is a label with no text. To simplify the game logic though, we maintain a separate 8×8 array of buttons. To allow keyboard functionality we use buttons for the … Read more
If you layer the layout managers correctly the screen will re-flow to different sizes for you, the idea is to use a single set of layout managers on ALL screen sizes. If you use null you will have to do each screen size yourself. Not only that but if the app can be windowed you … Read more
Use a 3×3 GridLayout For each of the 9 cells get a subimage: For every second component, add a label with the subimage. For every other component, add a JButton from which the space is removed. Use the subimage as icon, but you’ll need alternate icons to indicate focus, activation etc. This example puts a … Read more
Using various LayoutManagers one can provide spacing between various components. 1.) BorderLayout : Overloaded Constructor : BorderLayout(int horizontalGap, int verticalGap) Getter and setter methods For Horizontal Spacing : BorderLayout.getHgap() and BorderLayout.setHgap(int hgap) For Vertical Spacing : BorderLayout.getVgap() and BorderLayout.setVgap() 2.) FlowLayout : Overloaded Constructor : FlowLayout(int align, int hgap, int vgap) Getter and setter methods … Read more
Should I completely avoid the use of those methods? Yes for application code. The methods have been defined for a reason. So when should I use them? In which context? For what purposes? I don’t know, personally I think of it as an API design accident. Slightly forced by compound components having special ideas about … Read more
Nested/Combination Layout Example The Java Tutorial has comprehensive information on using layout managers. See the Laying Out Components Within a Container lesson for further details. One aspect of layouts that is not covered well by the tutorial is that of nested layouts, putting one layout inside another to get complex effects. The following code puts … Read more