![]() ![]() Many layout managers, however, simply place components based on the order they were added to their container. Some layout managers, such as GridBagLayout and SpringLayout, require elaborate setup procedures. The how-to section for each layout manager has details on what, if any, arguments you need to specify to the add method. Pane.add(aComponent, BorderLayout.PAGE_START) For example, BorderLayout requires that you specify the area to which the component should be added (using one of the constants defined in BorderLayout) using code like this: In fact, some layout managers do not even require you to add the component explicitly for example, GroupLayout. When you add components to a panel or content pane, the arguments you specify to the add method depend on the layout manager that the panel or content pane is using. It also does not adjust well to differences between users and systems, such as different font sizes and One drawback of absolute positioning is that it does not adjust well when the top-level container is resized. With this strategy, called absolute positioning, you must specify the size and position of every component within that container. By setting a container's layout property to null, you make the container use no layout manager. For example:Ĭontainer contentPane = frame.getContentPane() Īlthough we strongly recommend that you use layout managers, you can perform layout without them. You can set a panel's layout manager using the JPanel constructor. Again, you should use an appropriate tool to do this, rather than coding the manager by hand. Any real application will need to reset the layout manager. However, unless you are using JToolBar, the FlowLayout and BorderLayout managers are only useful for prototyping. ![]() If you do not like the default layout manager that a panel or content pane uses, you are free to change it to a different one. Content panes use BorderLayout by default. ![]() Each JPanel object is initialized to use a FlowLayout, unless you specify differently when creating the JPanel. This section discusses some of the common tasks related to using layout managers:Īs a rule, the only containers whose layout managers you need to worry about areĬontent panes. If you are interested in using JavaFX to create your GUI, see Otherwise, if you want to code by hand and do not want to use GroupLayout, then GridBagLayout is recommended as the next most flexible and powerful layout manager. If you are not interested in learning all the details of layout management, you might prefer to use the GroupLayout layout manager combined with a builder tool to lay out your GUI. Note: This lesson covers writing layout code by hand, which can be challenging. ![]()
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