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Trail: Creating a GUI with JFC/Swing
Lesson: User Interfaces that Swing: A Quick Start Guide

## Layout Management

> The following figure shows the GUIs of five programs, each of which displays five buttons. The buttons are identical, and the code for the programs is almost identical. So why do the GUIs look so different? Because they use different layout managers to control the size and the position of the buttons.

> The Java platform supplies five commonly used layout managers: `BorderLayout`, `BoxLayout`, `FlowLayout`, `GridBagLayout`, and `GridLayout`.

### Using Layout Managers

> By default, every container has a layout manager. All `JPanel` objects use a `FlowLayout` by default, whereas content panes (the main containers in `JApplet`, `JDialog`, and `JFrame` objects) use `BorderLayout` by default. As a rule, the only time you have to think about layout managers is when you create a `JPanel` or add components to a content pane. If you don't like the default layout manager that a panel or content pane uses, you can change it to a different one. Just invoke the container's `setLayout` method. For example, here's the code that makes a panel use `BorderLayout`:

> >     JPanel pane = new JPanel();
> >     pane.setLayout(new BorderLayout());

> When you add components to a panel or a content pane, the arguments you specify to the add method depend on the layout manager that the panel or content pane is using. So be sure to check the API documentation for the layout manager for details.

> Here's a quick summary of the various layout managers and where to find more information in The Java Tutorial and API documentation.

> `BorderLayout`
>   `BorderLayout` is the default layout manager for every content pane. The content pane is the main container in all frames, applets, and dialogs. A `BorderLayout` has five areas available to hold components: north, south, east, west, and center. All extra space is placed in the center area.

>   Tutorial: How to Use BorderLayout | API documentation: `BorderLayout`

> `BoxLayout`
>   The BoxLayout class puts components in a single row or column. This class respects the components' requested maximum sizes and also lets you align components.

>   Tutorial: How to Use BoxLayout | API documentation: `BoxLayout`

> `FlowLayout`
>   FlowLayout is the default layout manager for every JPanel. This layout manager simply lays out components from left to right, starting new rows, if necessary.

>   Tutorial: How to Use FlowLayout | API documentation: `FlowLayout`

> `GridLayout`
>   GridLayout simply makes a bunch of components equal in size and displays them in the requested number of rows and columns.

>   Tutorial: How to Use GridLayout | API documentation: `GridLayout`

> `GridBagLayout`
>   GridBagLayout is the most sophisticated, flexible layout manager the Java platform provides. This layout manager aligns components by placing them within a grid of cells, allowing some components to span more than one cell. The rows in the grid aren't necessarily all the same height; similarly, grid columns can have different widths.

>   Tutorial: How to Use GridBagLayout | API documentation: `GridBagLayout`

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