/*
* FlowController.java
*
* Created on May 9, 2007, 6:29 PM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/
package com.totsp.gwittir.client.flow;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.DeferredCommand;
import java.util.HashMap;
import java.util.Iterator;
import com.google.gwt.user.client.History;
import com.google.gwt.user.client.ui.HasWidgets;
import com.google.gwt.user.client.ui.Panel;
import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.UIObject;
import com.google.gwt.user.client.ui.Widget;
import com.totsp.gwittir.client.ui.BoundWidget;
import com.totsp.gwittir.client.ui.HasWidget;
/** The FlowController class is used to register FlowContexts to Widget maps for
* page to page or wizard style application flows. See the package doc for details.
*
* @author <a href="mailto:cooper@screaming-penguin.com">Robert "kebernet" Cooper</a>
*/
public class FlowController {
static final HashMap<Object, FlowContext> contexts = new HashMap<Object, FlowContext>();
static HistoryManager manager = null;
static final ValueChangeHandler<String> hl = new ValueChangeHandler<String>() {
public void onValueChange(ValueChangeEvent<String> event) {
if(manager != null) {
manager.apply(event.getValue());
}
}
};
static {
DeferredCommand.addCommand( new Command(){
public void execute() {
History.addValueChangeHandler(hl);
}
});
}
/**
* Calls a new flow context name, from the sender context with the given object model.
* @param sender The lowest level widget to begin looking for the name
* @param name The activity name to look for
* @param model The model object to pass to the registered BoundWidget
* @return boolean indicating whether the call resulted in a state change.
*/
public static boolean call(Widget sender, String name, Object model) {
return call(sender, name, model, true);
}
/**
* Calls a new flow context name, from the sender context with the given object model.
* @param sender The lowest level widget to begin looking for the name
* @param name The activity name to look for
* @param model The model object to pass to the registered BoundWidget
* @return boolean indicating whether the call resulted in a state change.
*/
public static boolean call(Widget sender, String name, Object model, boolean fireEvents) {
Widget contextRoot = sender;
FlowContext context = (FlowContext) contexts.get(contextRoot);
while((context == null) && (contextRoot != null)) {
contextRoot = contextRoot.getParent();
context = (FlowContext) contexts.get(contextRoot);
}
if(context == null || !(contextRoot instanceof HasWidgets || contextRoot instanceof HasWidget )) {
throw new RuntimeException(
"Unknown destination name for this elements context.");
}
Object panel = contextRoot;
BoundWidget<?> widget = context.get(name);
if(widget == null) {
return call(contextRoot.getParent(), name, model, fireEvents);
}
if(((Widget)widget).isAttached() ){
((Widget)widget).removeFromParent();
}
if( model != null ){
widget.setModel(model);
}
BoundWidget<?> old = null;
if( panel instanceof SimplePanel ){
SimplePanel sp = (SimplePanel) panel;
if( sp.getWidget() instanceof BoundWidget ){
old = (BoundWidget<?>) sp.getWidget();
}
sp.setWidget( (Widget) widget );
} else if( panel instanceof HasWidget ){
HasWidget hw = (HasWidget) panel;
if( hw.getWidget() instanceof BoundWidget ){
old = (BoundWidget<?>) hw.getWidget();
}
hw.setWidget( (Widget) widget );
} else if( panel instanceof HasWidgets ){
HasWidgets hw = (HasWidgets) panel;
Iterator<Widget> it = hw.iterator();
while(it.hasNext()) {
Object next = it.next();
if(next instanceof BoundWidget) {
old = (BoundWidget<?>) next;
break;
}
}
hw.clear();
hw.add((Widget) widget );
}
FlowEvent event = context.createEvent(contextRoot, name, widget, old );
if(fireEvents){
context.fireEvent(event);
}
if(manager != null ){
manager.transition(event, fireEvents);
}
return true;
}
/**
* Finds the first managed widget/panel from a source widget that has a name
* mapped in its flow context
* @param widget The low-level widget to search from
* @param name The name to search a flow context for
* @return the Managed widget that matches first.
*/
public static Widget findContextWidget(Widget widget, String name) {
Widget contextRoot = widget;
FlowContext context = (FlowContext) contexts.get(contextRoot);
while((context == null || context.get(name) == null) && (contextRoot != null) ) {
contextRoot = contextRoot.getParent();
context = (FlowContext) contexts.get(contextRoot);
}
return contextRoot;
}
/**
* Find the FlowContext with a name mapping from the low level widget
* @param widget Widget to begin searching from
* @param name activity name to find
* @return a FlowContext or null.
*/
public static FlowContext findContext(Widget widget, String name){
Widget contextRoot = widget;
FlowContext context = (FlowContext) contexts.get(contextRoot);
while((context == null || context.get(name) == null) && (contextRoot != null) ) {
contextRoot = contextRoot.getParent();
context = (FlowContext) contexts.get(contextRoot);
}
return context;
}
/**
* Returns the current HistoryManager implementation
* @return the current HistoryManager implementation
*/
public static HistoryManager getHistoryManager() {
return FlowController.manager;
}
/**
* Registers a managed widget with the given FlowContext
* @param container the widget to manage
* @param context The FlowContext it maps to.
*/
public static void setFlowContext(HasWidgets container, FlowContext context) {
contexts.put(container, context);
}
/**
* Registers a managed widget with the given FlowContext
* @param container the widget to manage
* @param context The FlowContext it maps to.
*/
public static void setFlowContext(HasWidget container, FlowContext context) {
contexts.put(container, context);
}
/** Registers a history manager for the FlowController globally.
*
* @param manager A history manager implementation
*/
public static void setHistoryManager(HistoryManager manager) {
FlowController.manager = manager;
}
/** Unregisters a FlowContext for a manage widget
*
* @param container Container to unregister
* @return boolean if there was a change.
*/
public static boolean unsetFlowContext(Panel container) {
return contexts.remove(container) != null;
}
}