Touchkit 4.1.0.alpha1 compilation error

compile widgetset errors ,How to solve that problem?

Compile with -strict or with -logLevel set to DEBUG or WARN to see all errors.
Tracing compile failure path for type ‘com.vaadin.addon.touchkit.gwt.client.vcom.navigation.NavigationManagerConnector’
[ERROR]
Errors in ‘jar:file:/C:/EclipseWorkspace/YH/Lib/vaadin-touchkit-cval-4.1.0.jar!/com/vaadin/addon/touchkit/gwt/client/vcom/navigation/NavigationManagerConnector.java’
[ERROR]
Line 110: The method getMessageHandler() is undefined for the type ApplicationConnection
[ERROR]
Line 115: The method getMessageHandler() is undefined for the type ApplicationConnection
[ERROR]
Hint: Check the inheritance chain from your module; it may not be inheriting a required module or a module may not be adding its source path entries properly
Computing all possible rebind results for ‘com.vaadin.client.ui.dd.VAcceptCriterionFactory’
Rebinding com.vaadin.client.ui.dd.VAcceptCriterionFactory
Invoking generator com.vaadin.server.widgetsetutils.AcceptCriteriaFactoryGenerator
Detecting available criteria …
creating mapping for com.vaadin.event.dd.acceptcriteria.AcceptAll
creating mapping for com.vaadin.event.dd.acceptcriteria.And
creating mapping for com.vaadin.event.dd.acceptcriteria.ContainsDataFlavor
creating mapping for com.vaadin.event.dd.acceptcriteria.SourceIs
creating mapping for com.vaadin.ui.AbstractSelect.TargetItemIs
creating mapping for com.vaadin.ui.AbstractSelect.AcceptItem
creating mapping for com.vaadin.ui.Table.TableDropCriterion
creating mapping for com.vaadin.ui.Tree.TreeDropCriterion
creating mapping for com.vaadin.event.dd.acceptcriteria.Not
creating mapping for com.vaadin.event.dd.acceptcriteria.Or
creating mapping for com.vaadin.event.dd.acceptcriteria.ServerSideCriterion
creating mapping for com.vaadin.event.dd.acceptcriteria.SourceIsTarget
creating mapping for com.vaadin.event.dd.acceptcriteria.TargetDetailIs
creating mapping for com.vaadin.ui.Tree.TargetInSubtree
Done. (0seconds)
Java HotSpot™ 64-Bit Server VM warning: ignoring option MaxPermSize=512M; support was removed in 8.0
Widgetset compilation failed

What Vaadin version are you using and how do you compile the widgetset? IIRC, TouchKit 4.1 requires a fairly recent version of Vaadin.

use Vaadin version 7.5.5 and Vaadin Plugin for Eclipse 3.0.0

Well, there’s your problem; TouchKit 4.1 requires Vaadin 7.6.0 or later. I also noticed that 4.1.0 (not alpha) has been out since January; you should be using that instead.