## Package com.google.gwt.user.client.ui

Widgets, Panels, and other user-interface classes.

See:
Description

Interface Summary
ChangeListener: Event listener interface for 'change' events.
ClickListener: Event listener interface for click events.
DisclosureHandler: Event handler interface for `DisclosureEvent`.
DisclosurePanelImages: An `ImageBundle` that provides images for `DisclosurePanel`.
FiresDisclosureEvents: A widget that implements this interface fires the events defined by the `DisclosureHandler` interface.
FiresFormEvents: A widget that implements this interface fires the events defined by the `FormHandler` interface.
FiresSuggestionEvents: A widget that implements this interface fires the events defined by the `SuggestionHandler` interface.
FocusListener: Event listener for focus events.
FormHandler: Handler interface for form submit events.
HasAlignment: A widget that implements this interface has an intrinsic alignment which can be manipulated using these methods and constants.
HasCaption: A widget that implements this interface has a caption which can be set and retrieved using these methods.
HasFocus: A widget that implements this interface can receive keyboard focus.
HasHorizontalAlignment: Characteristic interface which indicates that a widget can be aligned horizontally.
HasHTML: An object that implements this interface contains text, which can be set and retrieved using these methods.
HasKeyPreview: A class that implements this interface receives a preview of keyboard events before they are passed to the focused widget.
HasName: A widget that implements this interface has a 'name' associated with it, allowing it to be used with `FormPanel`.
HasText: An object that implements this interface contains text, which can be set and retrieved using these methods.
HasVerticalAlignment: Characteristic interface which indicates that a widget has an associated vertical alignment.
HasWidgets: A widget that implements this interface contains `widgets` and can enumerate them.
HasWordWrap: A widget that implements this interface has a 'word-wrap' property that can be manipulated using these methods.
HorizontalSplitPanelImages: An `ImageBundle` that provides images for `HorizontalSplitPanel`.
ImageBundle: A tag interface that is used in the generation of image bundles.
IndexedPanel: A panel that imposes an explicit ordering on its children.
KeyboardListener: Event listener interface for keyboard events.
LoadListener: Event listener interface for 'load' events.
MouseListener: Event listener interface for mouse events.
MouseWheelListener: Event listener interface for mouse wheel events.
PopupListener: Event listener interface for popup events.
PopupPanel.PositionCallback: A callback that is used to set the position of a `PopupPanel` right before it is shown.
RichTextArea.BasicFormatter: This interface is used to access basic formatting options, when available.
RichTextArea.ExtendedFormatter: This interface is used to access full formatting options, when available.
ScrollListener: Event listener interface for scroll events.
SourcesChangeEvents: A widget that implements this interface sources the events defined by the `ChangeListener` interface.
SourcesClickEvents: A widget that implements this interface sources the events defined by the `ClickListener` interface.
SourcesFocusEvents: A widget that implements this interface sources the events defined by the `FocusListener` interface.
SourcesKeyboardEvents: A widget that implements this interface sources the events defined by the `KeyboardListener` interface.
SourcesLoadEvents: A widget that implements this interface sources the events defined by the `LoadListener` interface.
SourcesMouseEvents: A widget that implements this interface sources the events defined by the `MouseListener` interface.
SourcesMouseWheelEvents: A widget that implements this interface sources the events defined by the `MouseWheelListener` interface.
SourcesPopupEvents: A widget that implements this interface sources the events defined by the `PopupListener` interface.
SourcesScrollEvents: A widget that implements this interface sources the events defined by the `ScrollListener` interface.
SourcesTabEvents: A widget that implements this interface sources the events defined by the `TabListener` interface.
SourcesTableEvents: A widget that implements this interface sources the events defined by the `TableListener` interface.
SourcesTreeEvents: A widget that implements this interface sources the events defined by the `TreeListener` interface.
SuggestionHandler: Event handler interface for `SuggestionEvent`.
SuggestOracle.Callback: Callback for `SuggestOracle`.
SuggestOracle.Suggestion: Suggestion supplied by the `SuggestOracle`.
TableListener: Event listener interface for table events.
TabListener: Event listener interface for tab events, used primarily by `TabBar` and `TabPanel`.
TreeImages: An `ImageBundle` that provides images for `Tree`.
TreeListener: Event listener interface for tree events.
VerticalSplitPanelImages: An `ImageBundle` that provides images for `HorizontalSplitPanel`.

Class Summary
AbsolutePanel: An absolute panel positions all of its children absolutely, allowing them to overlap.
AbstractImagePrototype: An opaque representation of a particular image such that the image can be accessed either as an HTML fragment or as an `Image` object.
Button: A standard push-button widget.
ButtonBase: Abstract base class for `Button`, `CheckBox`, `RadioButton`.
CellPanel: A panel whose child widgets are contained within the cells of a table.
ChangeListenerCollection: A helper class for implementers of the SourcesChangeEvents interface.
CheckBox: A standard check box widget (also serves as a base class for `RadioButton`.
ClickListenerCollection: A helper class for implementers of the SourcesClickEvents interface.
ComplexPanel: Abstract base class for panels that can contain multiple child widgets.
Composite: A type of widget that can wrap another widget, hiding the wrapped widget's methods.
CustomButton: Custom Button is a base button class with built in support for a set number of button faces.
DeckPanel: A panel that displays all of its child widgets in a 'deck', where only one can be visible at a time.
DelegatingChangeListenerCollection: `ChangeListenerCollection` used to correctly hook up listeners which need to listen to events from another source.
DelegatingClickListenerCollection: `ClickListenerCollection` used to correctly hook up listeners which need to listen to events from another source.
DelegatingFocusListenerCollection: `FocusListenerCollection` used to correctly hook up listeners which need to listen to events from another source.
DelegatingKeyboardListenerCollection: `KeyboardListenerCollection` used to correctly hook up event listeners to the composite's wrapped widget.
DialogBox: A form of popup that has a caption area at the top and can be dragged by the user.
DisclosureEvent: Event object containing information about `DisclosurePanel` changes.
DisclosurePanel: A widget that consists of a header and a content panel that discloses the content when a user clicks on the header.
DockPanel: A panel that lays its child widgets out "docked" at its outer edges, and allows its last widget to take up the remaining space in its center.
DockPanel.DockLayoutConstant: DockPanel layout constant, used in `DockPanel.add(Widget, DockPanel.DockLayoutConstant)`.
FileUpload: A widget that wraps the HTML <input type='file'> element.
FlexTable: A flexible table that creates cells on demand.
FlowPanel: A panel that formats its child widgets using the default HTML layout behavior.
FocusListenerAdapter: An adapter to simplify focus event listeners that do not need all events defined on the FocusListener interface.
FocusListenerCollection: A helper class for implementers of the `SourcesFocusEvents` interface.
FocusPanel: A simple panel that makes its contents focusable, and adds the ability to catch mouse and keyboard events.
FocusWidget: Abstract base class for most widgets that can receive keyboard focus.
FormHandlerCollection: Helper class for widgets that accept `FormHandlers`.
FormPanel: A panel that wraps its contents in an HTML <FORM> element.
FormSubmitCompleteEvent: Event object containing information about form submission events.
FormSubmitEvent: Event object containing information about form submission events.
Frame: A widget that wraps an IFRAME element, which can contain an arbitrary web site.
Grid: A rectangular grid that can contain text, html, or a child `Widget` within its cells.
HasHorizontalAlignment.HorizontalAlignmentConstant: Horizontal alignment constant.
HasVerticalAlignment.VerticalAlignmentConstant: Horizontal alignment constant.
Hidden: Represents a hidden field in an HTML form.
HorizontalPanel: A panel that lays all of its widgets out in a single horizontal column.
HorizontalSplitPanel: A panel that arranges two widgets in a single horizontal row and allows the user to interactively change the proportion of the width dedicated to each of the two widgets.
HTML: A widget that can contain arbitrary HTML.
HTMLPanel: A panel that contains HTML, and which can attach child widgets to identified elements within that HTML.
HTMLTable: HTMLTable contains the common table algorithms for `Grid` and `FlexTable`.
Hyperlink: A widget that serves as an "internal" hyperlink.
Image: A widget that displays the image at a given URL.
KeyboardListenerAdapter: An adapter to simplify keyboard event listeners that do not need all events defined on the KeyboardListener interface.
KeyboardListenerCollection: A helper class for implementers of the SourcesKeyboardEvents interface.
Label: A widget that contains arbitrary text, not interpreted as HTML.
ListBox: A widget that presents a list of choices to the user, either as a list box or as a drop-down list.
LoadListenerCollection: A helper class for implementers of the SourcesLoadEvents interface.
MenuBar: A standard menu bar widget.
MenuItem: A widget that can be placed in a `MenuBar`.
MouseListenerAdapter: An adapter to simplify mouse event listeners that do not need all events defined on the MouseListener interface.
MouseListenerCollection: A helper class for implementers of the SourcesMouseEvents interface.
MouseWheelListenerCollection: A helper class for implementers of the SourcesMouseWheelEvents interface.
MouseWheelVelocity: Encapsulates the direction and velocity of mouse wheel events.
MultiWordSuggestOracle: The default `SuggestOracle`.
MultiWordSuggestOracle.MultiWordSuggestion: Suggestion class for `MultiWordSuggestOracle`.
NamedFrame: A `Frame` that has a 'name' associated with it.
Panel: Abstract base class for all panels, which are widgets that can contain other widgets.
PasswordTextBox: A text box that visually masks its input to prevent eavesdropping.
PopupListenerCollection: A helper class for implementers of the SourcesPopupEvents interface.
PopupPanel: A panel that can "pop up" over other widgets.
PushButton: A normal push button with custom styling.
RadioButton: A mutually-exclusive selection radio button widget.
RichTextArea: A rich text editor that allows complex styling and formatting.
RichTextArea.FontSize: Font size enumeration.
RichTextArea.Justification: Justification enumeration.
RootPanel: The panel to which all other widgets must ultimately be added.
ScrollListenerCollection: A helper class for implementers of the SourcesScrollEvents interface.
ScrollPanel: A simple panel that wraps its contents in a scrollable area.
SimplePanel: Abstract base class for panels that contain only one widget.
StackPanel: A panel that stacks its children vertically, displaying only one at a time, with a header for each child which the user can click to display.
SuggestBox: A `SuggestBox` is a text box or text area which displays a pre-configured set of selections that match the user's input.
SuggestionEvent: Event object containing information about the selection of a `SuggestOracle.Suggestion` displayed by a `SuggestBox`.
SuggestOracle: A `SuggestOracle` can be used to create suggestions associated with a specific query string.
SuggestOracle.Request: A `SuggestOracle` request.
SuggestOracle.Response: `SuggestOracle` response.
TabBar: A horizontal bar of folder-style tabs, most commonly used as part of a `TabPanel`.
TableListenerCollection: A helper class for implementers of the `SourcesTableEvents` interface.
TabListenerCollection: A helper class for implementers of the `SourcesTabEvents` interface.
TabPanel: A panel that represents a tabbed set of pages, each of which contains another widget.
TextArea: A text box that allows multiple lines of text to be entered.
TextBox: A standard single-line text box.
TextBoxBase: Abstract base class for all text entry widgets.
TextBoxBase.TextAlignConstant: Text alignment constant, used in `TextBoxBase.setTextAlignment(TextBoxBase.TextAlignConstant)`.
ToggleButton: A `ToggleButton` is a stylish stateful button which allows the user to toggle between `up` and `down` states.
Tree: A standard hierarchical tree widget.
TreeItem: An item that can be contained within a `Tree`.
TreeListenerCollection: A helper class for implementers of the SourcesClickEvents interface.
UIObject: The superclass for all user-interface objects.
VerticalPanel: A panel that lays all of its widgets out in a single vertical column.
VerticalSplitPanel: A panel that arranges two widgets in a single vertical column and allows the user to interactively change the proportion of the height dedicated to each of the two widgets.
Widget: The base class for the majority of user-interface objects.
WidgetCollection: A simple collection of widgets to be used by `panels` and `composites`.

## Package com.google.gwt.user.client.ui Description

Widgets, Panels, and other user-interface classes. This package contains all of the high-level user-interface Widgets, along with panels and event interfaces. These classes form the bulk of the client-side libraries used by GWT applications.