Swing BoxLayout

BoxLayout allows multiple components to be laid out either vertically or horizontally. The components will not wrap so, for example, a vertical arrangement of components will stay vertically arranged when the frame is resized. Nesting multiple panels with different combinations of horizontal and vertical gives an effect similar to GridBagLayout, without the complexity. The BoxLayout manager is constructed with an axis parameter that specifies the type of layout that will be done. For all directions, components are arranged in the same order as they were added to the container.

BoxLayout attempts to arrange components at their preferred widths (for horizontal layout) or heights (for vertical layout). For a horizontal layout, if not all the components are the same height, BoxLayout attempts to make all the components as high as the highest component. If that's not possible for a particular component, then BoxLayout aligns that component vertically, according to the component's Y alignment. By default, a component has a Y alignment of 0.5, which means that the vertical center of the component should have the same Y coordinate as the vertical centers of other components with 0.5 Y alignment. Similarly, for a vertical layout, BoxLayout attempts to make all components in the column as wide as the widest component. If that fails, it aligns them horizontally according to their X alignments.

Main Features

  • Select BoxLayout from the Layouts palette and drop it on a JFrame or JPanel

  • Graphical feedback is provided for all drop and move interactions

 

  • Graphically show area occupied by struts and springs (glue)

  • Graphically resize struts and rigid areas via dragging

 

  • Direct-edit (hit space bar) struts and rigid areas to resize them

 

 

 

  • Widget alignment within the BoxLayout can be set using the Property Pane

  • Note that struts and rigid areas can be used as invisible spacer objects in other layouts as well

 

 

Graphical Feedback

  • When moving a widget or adding a new widget, the current drop point is highlighted in red

     
     
     
  • Resize struts and rigid areas by dragging or direct edit