org.eclipse.rwt.lifecycle
Interface IWidgetLifeCycleAdapter

All Superinterfaces:

ILifeCycleAdapter

All Known Implementing Classes:

AbstractWidgetLCA

public interface IWidgetLifeCycleAdapter
extends ILifeCycleAdapter

A stateless callback handler used by RWT to synchronize the client-side and server-side state of a widget. Each widget type should provide its own implementation of this interface.

Since:

1.0

See Also:

AbstractWidgetLCA, WidgetLCAUtil

Method Summary

void	preserveValues(Widget widget) Preserves the current state of the widget in order to be able to keep track of changes.
void	readData(Widget widget) Reads request parameters and applies the state changes that are indicated by the client to the widget.
void	render(Widget widget) Writes JavaScript code to the response that renders the changes that has been made to the widget.

Method Detail

preserveValues

void preserveValues(Widget widget)

Preserves the current state of the widget in order to be able to keep track of changes. This method is called after the Read Data phase but before the Process Action phase of the request life cycle. Thus, the client and server state is in sync. By preserving the current state of the widget, it is later possible to identify the properties that have been modified during the processing of the request.

Implementors can use the method IWidgetAdapter.preserve(String, Object). As a rule of thumb, every property that is written in render must be preserved in this method.

Parameters:

widget - the widget, the properties of which are preserved

readData

void readData(Widget widget)

Reads request parameters and applies the state changes that are indicated by the client to the widget. This method is called during the Read Data phase of the request life cycle.

Parameters:

widget - the widget to be processed

render

void render(Widget widget)
            throws java.io.IOException

Writes JavaScript code to the response that renders the changes that has been made to the widget.

Parameters:

widget - the widget to render changes for

Throws:

java.io.IOException