Hi,
I’m trying out the introduction to Vaadin 7 w/ Eclipse and Tomcat video tutorial at https://vaadin.com/learn.
I am having problems occuring at 6:12 in the video where the docList.addvalueChangeListener is added
and changes the docView.setPropertyDataSource. This is to allow the content of the html file to display in the right panel.
Basically on line 36 of DocUI, I get a ClassCastException saying the ComboBox cannot be cast to java.io.File.
I was able to do the previous example (populating the file list and creating the split view) without any problem.
I am using Vaadim 7.0.2, Java 1.6.0_27, Tomcat 6.0.36, & Eclipse Juno.
Any help would be appreciated.
Thank you,
Tim
DocUI.java and stack trace listed below:
Here is my DocUI:
package com.example.documentmanager;
import java.io.File;
import com.vaadin.data.Property.ValueChangeEvent;
import com.vaadin.data.Property.ValueChangeListener;
import com.vaadin.data.util.FilesystemContainer;
import com.vaadin.data.util.TextFileProperty;
import com.vaadin.server.VaadinRequest;
import com.vaadin.shared.ui.label.ContentMode;
import com.vaadin.ui.Button;
import com.vaadin.ui.Button.ClickEvent;
import com.vaadin.ui.ComboBox;
import com.vaadin.ui.HorizontalSplitPanel;
import com.vaadin.ui.Label;
import com.vaadin.ui.UI;
import com.vaadin.ui.VerticalLayout;
@SuppressWarnings(“serial”)
public class DocUI extends UI {
FilesystemContainer docs = new FilesystemContainer(new File("D:/test"));
ComboBox docList = new ComboBox("Documents", docs);
Label docView = new Label("", ContentMode.HTML);
@Override
protected void init(VaadinRequest request) {
HorizontalSplitPanel split = new HorizontalSplitPanel();
setContent(split);
split.addComponent(docList);
split.addComponent(docView);
docList.addValueChangeListener( new ValueChangeListener() {
public void valueChange(ValueChangeEvent event) {
docView.setPropertyDataSource(new TextFileProperty((File) event.getProperty()));
}
});
docList.setImmediate(true);
}
}
and stack trace:
com.vaadin.event.ListenerMethod$MethodException: Invocation of method valueChange in com.example.documentmanager.DocUI$1 failed.
at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:528)
at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:167)
at com.vaadin.server.AbstractClientConnector.fireEvent(AbstractClientConnector.java:984)
at com.vaadin.ui.AbstractField.fireValueChange(AbstractField.java:1099)
at com.vaadin.ui.AbstractField.setValue(AbstractField.java:534)
at com.vaadin.ui.AbstractSelect.setValue(AbstractSelect.java:702)
at com.vaadin.ui.ComboBox.changeVariables(ComboBox.java:664)
at com.vaadin.server.AbstractCommunicationManager.changeVariables(AbstractCommunicationManager.java:1889)
at com.vaadin.server.AbstractCommunicationManager.handleBurst(AbstractCommunicationManager.java:1693)
at com.vaadin.server.AbstractCommunicationManager.handleVariables(AbstractCommunicationManager.java:1566)
at com.vaadin.server.AbstractCommunicationManager.handleUidlRequest(AbstractCommunicationManager.java:582)
at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:315)
at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:201)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.ClassCastException: com.vaadin.ui.ComboBox cannot be cast to java.io.File
at com.example.documentmanager.DocUI$1.valueChange(DocUI.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:508)
… 25 more