org.eclipse.rap.rwt.lifecycle
Class WidgetUtil

java.lang.Object
  org.eclipse.rap.rwt.lifecycle.WidgetUtil

public final class WidgetUtil
extends java.lang.Object

This is a helper class to obtain different aspects for a widget related to the handling of widgets in RAP.

Since:

2.0

Field Summary

static java.lang.String	CUSTOM_VARIANT Deprecated. Use RWT.CUSTOM_VARIANT instead
static java.lang.String	CUSTOM_WIDGET_ID Note: This constant is provisional and subject to change without further notice.
static java.lang.String	ENABLE_UI_TESTS Deprecated. The system property has been moved to the internal class RWTProperties. Please look up the name in the documentation of CUSTOM_WIDGET_ID.

Method Summary

static Widget	find(Composite root, java.lang.String id) This method searches for a widget with the given id within the widget hierarchy starting at root.
static WidgetAdapter	getAdapter(Widget widget) Returns the according WidgetAdapter for a specified widget.
static java.lang.String	getId(Widget widget) Returns the id of the given widget that is used to identify the widget on the client.
static AbstractWidgetLCA	getLCA(Widget widget) Returns the AbstractWidgetLCA instance for this widget.
static java.lang.String	getVariant(Widget widget) Returns the widget variant defined for the given widget using Widget.setData().
static void	registerDataKeys(java.lang.String... keys) Adds keys to the list of keys of widget data that are synchronized with the client.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

CUSTOM_VARIANT

@Deprecated
public static final java.lang.String CUSTOM_VARIANT

Deprecated. Use RWT.CUSTOM_VARIANT instead

See Also:

Constant Field Values

CUSTOM_WIDGET_ID

public static final java.lang.String CUSTOM_WIDGET_ID

Note: This constant is provisional and subject to change without further notice.

This constant can be used to apply a custom widget id to a widget. By default, the framework applies a unique widget id to every widget. This id is used to identify the widget in the client/server protocol. For UI tests, it can be helpful to replace these generated ids with custom ids in order to make the ids more human-readable and more stable against changes in the UI. The following snippet applies a custom widget id to a widget:

 widget.setData( WidgetUtil.CUSTOM_WIDGET_ID, "myCustomId" )
 

The support for custom widget ids must be explicitly enabled by setting the system property org.eclipse.rap.rwt.enableUITests to true. If activated, the default web client will also set the HTML id attribute for every widget that are rendered to the client to the widget id.

A custom widget id must be unique within the user session. It is the clients' responsibility to choose a unique id. Assigning an id that is used by another widget will lead to indeterministic behavior.

A custom widget id must only contain characters that are valid according to the W3C recommendation for id and name attributes.

See Also:

Widget.setData(String,Object), getId(Widget), Constant Field Values

ENABLE_UI_TESTS

@Deprecated
public static final java.lang.String ENABLE_UI_TESTS

Deprecated. The system property has been moved to the internal class RWTProperties. Please look up the name in the documentation of CUSTOM_WIDGET_ID.

See Also:

CUSTOM_WIDGET_ID

Method Detail

getAdapter

public static WidgetAdapter getAdapter(Widget widget)

Returns the according WidgetAdapter for a specified widget.

Parameters:

widget - the widget

Returns:

the WidgetAdapter instance

getId

public static java.lang.String getId(Widget widget)

Returns the id of the given widget that is used to identify the widget on the client.

Parameters:

widget - the widget to obtain the id for, must not be null

Returns:

the id for the given widget

getVariant

public static java.lang.String getVariant(Widget widget)

Returns the widget variant defined for the given widget using Widget.setData().

Parameters:

widget - the widget whose variant is requested

Returns:

the variant or null if no variant has been specified for the given widget

getLCA

public static AbstractWidgetLCA getLCA(Widget widget)

Returns the AbstractWidgetLCA instance for this widget.

Parameters:

widget - the widget to obtain the life cycle adapter from

Returns:

the life cycle adapter for the given widget

find

public static Widget find(Composite root,
                          java.lang.String id)

This method searches for a widget with the given id within the widget hierarchy starting at root.

Parameters:

root - the root widget where to start the search

id - the id of the widget to search for

Returns:

the widget or null if there was no widget found with the given id within the widget hierarchy

registerDataKeys

public static void registerDataKeys(java.lang.String... keys)

Adds keys to the list of keys of widget data that are synchronized with the client. It is save to add the same key twice, there are no side-effects. The method has to be called from the UI thread and affects the entire UI-session. The data is only transferred from server to client, not back.

Note: This method is considered provisional and may change again until the final release.

Parameters:

keys - The keys to add to the list.

Since:

2.2

See Also:

Widget.setData(String, Object)