Eclipse Rich Ajax Platform
Release 1.3

org.eclipse.rwt.lifecycle
Class WidgetUtil

java.lang.Object
  extended byorg.eclipse.rwt.lifecycle.WidgetUtil

public final class WidgetUtil
extends Object

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

Since:
1.0

Field Summary
static String CUSTOM_VARIANT
          Used to mark a widget as belonging to a custom variant using Widget.setData.
static String CUSTOM_WIDGET_ID
          Note: This constant is provisional and subject to change without further notice.
static String ENABLE_UI_TESTS
          Note: This constant is provisional and subject to change without further notice.
 
Method Summary
static Widget find(Composite root, String id)
          This method searches for a widget with the given id within the widget hierachy starting at root.
static IWidgetAdapter getAdapter(Widget widget)
          Returns the according IWidgetAdapter for a specified widget.
static 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 String getVariant(Widget widget)
          Returns the widget variant defined for the given widget using Widget.setData().
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

CUSTOM_VARIANT

public static final String CUSTOM_VARIANT
Used to mark a widget as belonging to a custom variant using Widget.setData. For more information on custom widget variants, see the RAP help on theming.

Since:
1.1
See Also:
Widget.setData(String,Object), Constant Field Values

CUSTOM_WIDGET_ID

public static final String CUSTOM_WIDGET_ID

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

By default, the widget-id returned by IWidgetAdapter.getId() is an automatically generated value that is session-wide unique. A custom id can be assigned by using the Widget#setData(String, Object) method and using this constant for the key argument and a string that denotes the new id as the data argument. In addition the system property denoted by ENABLE_UI_TESTS must be set to true.

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

It is the clients' responsibility to choose a unique id. Assigning an id that is used by another widget will lead to indeterministic behavior.

The following code would assign the id 'myId' to the widget:

   Widget widget = new ...
   widget.setData( WidgetUtil.CUSTOM_WIDGET_ID, "myId" );
 

Since:
1.1
See Also:
Widget.setData(String,Object), getId(Widget), ENABLE_UI_TESTS, Constant Field Values

ENABLE_UI_TESTS

public static final String ENABLE_UI_TESTS

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

If a system property with this name is set to true, the UI testing support is activated. For all widgets that are rendered to the client, the HTML id attribute is set.

In conjunction with CUSTOM_WIDGET_ID, each widget can be assigned a custom, more human-readable, identifier that is independant if the order in which widgets are created.

Since:
1.1
See Also:
CUSTOM_WIDGET_ID, Constant Field Values
Method Detail

getAdapter

public static IWidgetAdapter getAdapter(Widget widget)
Returns the according IWidgetAdapter for a specified widget.

Parameters:
widget - the widget
Returns:
the IWidgetAdapter instance

getId

public static 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 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,
                          String id)
This method searches for a widget with the given id within the widget hierachy 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

Eclipse Rich Ajax Platform
Release 1.3

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