CODEWITHSUNDEEP
javagwt
Gandalf
Gandalf

Reputation: 13693

My first gwt app do not show the buttons

I am getting started on gwt and I can't understand why my app cannot show any buttons even though in my code I have indicated a button to be created.

My Entry point class is 

package com.france.webapp.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;

public class MyEntryPoint implements EntryPoint {

public MyEntryPoint(){
}

    @Override
    public void onModuleLoad() {
    Label label = new Label("Hello GWT !!!");
    Button button = new Button("Say something");

    button.addClickHandler(new ClickHandler() {
      @Override
      public void onClick(ClickEvent event) {
        Window.alert("Hello, again");
      }
    });

    RootPanel.get().add(label);
    RootPanel.get().add(button);
  }
}

I am on windows with the latest version of jdk and eclipse juno.My app runs and the html page is shown but with no button. I have tested it with the latest version of chrome and firefox 20 with the gwt development plugin.

Do i have to compile the project or will the Run As -> Web Application option be enough to display the buttons? My gwt.xml looks fine and I am following the tutorial at http://www.vogella.com/articles/GWT/article.html

This is my MyModule.gwt.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE module PUBLIC "-//Google Inc.//DTD Google Web Toolkit 2.5.1//EN" "http://google-web-toolkit.googlecode.com/svn/tags/2.5.1/distro-source/core/src/gwt-module.dtd">
<module>
    <inherits name="com.google.gwt.user.User" />
    <source path="client" />
    <entry-point class="com.france.webapp.client.MyEntryPoint"></entry-point>
</module>

My html.html file

<!doctype html>
<html>
  <head>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8">
    <title>html</title>
    <script type="text/javascript" language="javascript" src=".nocache.js"></script>
  </head>

  <body>
    <iframe src="javascript:''" id="__gwt_historyFrame" tabIndex='-1' style="position:absolute;width:0;height:0;border:0"></iframe>

  </body>
</html>

I have looked at the eclipse console and this is what it reads

[WARN] 404 - GET /.nocache.js (127.0.0.1) 1397 bytes
   Request headers
      Host: 127.0.0.1:8888
      Connection: keep-alive
      Accept: */*
      User-Agent: Mozilla/5.0 (Windows NT 5.1) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.64 Safari/537.31
      Accept-Encoding: gzip,deflate,sdch
      Accept-Language: en-US,en;q=0.8
      Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
      Referer: http://127.0.0.1:8888/html.html?gwt.codesvr=127.0.0.1:9997

Upvotes: 1

Views: 1349

Answers (1)

K Boden
K Boden

Reputation: 626

It is likely a problem with your html file. I ran your code successfully, try this as the contents of your html file under the war folder in your project:

<!doctype html>
<!-- The DOCTYPE declaration above will set the     -->
<!-- browser's rendering engine into                -->
<!-- "Standards Mode". Replacing this declaration   -->
<!-- with a "Quirks Mode" doctype is not supported. -->

<html>
  <head>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8">

    <!--                                                               -->
    <!-- Consider inlining CSS to reduce the number of requested files -->
    <!--                                                               -->
    <link type="text/css" rel="stylesheet" href="MyEntryPoint.css">

    <!--                                           -->
    <!-- Any title is fine                         -->
    <!--                                           -->
    <title>Web Application Starter Project</title>

    <!--                                           -->
    <!-- This script loads your compiled module.   -->
    <!-- If you add any GWT meta tags, they must   -->
    <!-- be added before this line.                -->
    <!--                                           -->
    <script type="text/javascript" language="javascript" src="myentrypoint/myentrypoint.nocache.js"></script>
  </head>
  <body>
  </body>
</html>

And make sure this is in your project xxx.gwt.xml under your com.france.webapp package:

<entry-point class='com.france.webapp.client.MyEntryPoint'/>

It does take a few seconds, sometimes 10 or more, for the widgets to load when running the app through Eclipse/jetty.

Upvotes: 1

Related Questions