The FocusEvent class in java programming

The component-level focus event. There are two levels of focus change events: permanent and temporary. Permanent focus change events occur when focus is directly moved from one component to another, such as through calls to requestFocus() or as the user uses the Tab key to traverse components. Temporary focus change events occur when focus is temporarily gained or lost for a component as the indirect result of another operation, such as window deactivation or a scroll bar drag. In this case, the original focus state will automatically be restored once that operation is finished, or, for the case of window deactivation, when the window is reactivated. Both permanent and temporary focus events are delivered using the FOCUS_GAINED and FOCUS_LOST event ids; the levels may be distinguished in the event using the isTemporary() method

FocusEvent(Component, int)

Constructs a permanent-level FocusEvent object with the specified source component and type.

sssssFocusEvent(Component, int, boolean)

Constructs a FocusEvent object with the specified source component, type, and whether or not the focus event is a temporary level event.

Method Detail

isTemporary

public boolean isTemporary()

Identifies the focus change event as temporary or permanent.

Returns:

true if the focus change is temporary; false otherwise

getOppositeComponent

public Component getOppositeComponent()

Returns the other Component involved in this focus change.

 For a FOCUS_GAINED event, this is the Component that lost focus. For a
FOCUS_LOST event, this is the Component that gained focus. 

If this focus change occurs with a native application, with a Java application
in a different VM or context, or with no other Component, then null is
returned.

Returns:

the other Component involved in the focus change, or null

paramString

public String paramString()

Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.

Overrides:

paramString in class ComponentEvent

Returns:

a string identifying the event and its attributes