To achieve proper alignment within a BoxLayout, it's crucial to ensure that all components share the same setAlignmentX(...) values. Typically, panels use 0.5f as the default value, while other components use 0.0f. Modifying these values can significantly impact the layout and alignment of your components.
Consider experimenting with BoxLayout.X_AXIS and BoxLayout.Y_AXIS to control the orientation of the layout. These properties determine whether the components are arranged horizontally or vertically.
To center all components within the layout, make sure that the alignmentX and alignmentY properties are set to the same value, typically 0.5. If you specify 0.5 for one axis and a different value for the other, the components will be misaligned.
Furthermore, keep in mind that the Page Axis property reverses the axes. Therefore, if you want to center components horizontally and vertically, you need to set alignmentX and alignmentY to the same value, such as 0.5, and select BoxLayout.Y_AXIS for the Page Axis property.