[Chapter 6] 6.2 Panel

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| Chapter 6 Containers |

## 6.2 Panel

The `Panel` class provides a generic container within an existing display area. It is the simplest of all the containers. When you load an applet into Netscape Navigator or an appletviewer, you have a `Panel` to work with at the highest level.

A `Panel` has no physical appearance. It is just a rectangular display area. The default `LayoutManager` of `Panel` is `FlowLayout`; `FlowLayout` is described in FlowLayout.

### Panel Methods

Constructors

public Panel ()

  The first constructor creates a `Panel` with a `LayoutManager` of `FlowLayout`.

public Panel (LayoutManager layout)

  This constructor allows you to set the initial `LayoutManager` of the new `Panel` to `layout`. If `layout` is `null`, there is no `LayoutManager`, and you must shape and position the components within the `Panel` yourself.

Miscellaneous methods

public void addNotify ()

  The `addNotify()` method creates the `Panel` peer. If you override this method, first call `super.addNotify()`, then add your customizations for the new class. Then you can do everything you need with the information about the newly created peer.

### Panel Events

In Java 1.0, a `Panel` peer generates all the events that are generated by the `Component` class; it does not generate events that are specific to a particular type of component. That is, it generates key events, mouse events, and focus events; it doesn't generate action events or list events. If an event happens within a child component of a `Panel`, the target of the event is the child component, not the `Panel`. There's one exception to this rule: if a component uses the `LightweightPeer` (new to Java 1.1), it cannot be the target of an event.

With Java 1.1, events are delivered to whatever listener is associated with a contained component. The fact that the component is within a `Panel` has no relevance.

Container |  | Insets