How to develop a Gantt Chart Userview Menu

In this tutorial, we will following the guideline of developing a plugin to develop our Gantt Chart Userview Menu plugin. Please also refer to the very first tutorial How to develop a Bean Shell Hash Variable for more details steps.

1. What is the problem?

I want to display collected form data in a gantt chart view. I can choose to use Jasper Reports Userview Menu to achieve it but It does not look nice and lack of interactive control. Then, I found this Jquery Gantt Chart library developed by Tait Brown under MIT license which look nicer and work better than viewing a gantt chart using Jasper Report. I want to use it to display my collected form data.

2. What is your idea to solve the problem?

We can develop a Userview Menu Plugin to use the Jquery Gantt Chart library to display the collected form data.

3. What is the input needed for your plugin?

To develop a Gantt Chart Userview Menu plugin, we can consider to provide the following as input.

1. Data Binder : We can reuse datalist binder to retrieve data
2. Data Mapping : Map the retrieve data from datalist binder to the data format of the library
3. Formatting options : Options to format and customise the gantt chart. 

4. What is the output and expected outcome of your plugin?

By referring to the library demo, we can quickly come out a static HTML page like the picture below. As this is a Joget plugin tutorial, we will not go into the detail on coding the static HTML page. You can refer to static.zip.

5. Is there any resources/API that can be reuse?

To develop the PDF Download Datalist Action plugin, we can reuse the methods in FormPdfUtil to generate a form as PDF. We can also refer to the source code of the Datalist Form Data Delete Action plugin as well. Other than that, we can refer to the Export Form Email Tool on what kind of plugin properties options we can provide in the plugin as the Export Form Email Tool are using the methods in FormPdfUtil as well.

6. Prepare your development environment

We need to always have our Joget Workflow Source Code ready and builded by following this guideline. 

The following of this tutorial is prepared with a Macbook Pro and Joget Source Code version 5.0.0. Please refer to Guideline of developing a plugin for other platform command.

Let said our folder directory as following. 

- Home
  - joget
    - plugins
    - jw-community
      -5.0.0

The "plugins" directory is the folder we will create and store all our plugins and the "jw-community" directory is where the Joget Workflow Source code stored.

Run the following command to create a maven project in "plugins" directory.

cd joget/plugins/
~/joget/jw-community/5.0.0/wflow-plugin-archetype/create-plugin.sh org.joget.tutorial gantt_chart_menu 5.0.0

Then, the shell script will ask us to key in a version for your plugin and ask us for confirmation before generate the maven project.

Define value for property 'version':  1.0-SNAPSHOT: : 5.0.0
[INFO] Using property: package = org.joget.tutorial
Confirm properties configuration:
groupId: org.joget.tutorial
artifactId: gantt_chart_menu
version: 5.0.0
package: org.joget.tutorial
Y: : y

We should get "BUILD SUCCESS" message shown in our terminal and a "gantt_cahrt_menu" folder created in "plugins" folder.

Open the maven project with your favour IDE. I will be using NetBeans.  

7. Just code it!

a. Extending the abstract class of a plugin type

Create a "GanttChartMenu" class under "org.joget.tutorial" package. Then, extend the class with org.joget.apps.userview.model.UserviewMenu abstract class. Please refer to Userview Menu Plugin.

b. Implement all the abstract methods

As usual, we have to implement all the abstract methods. We will using AppPluginUtil.getMessage method to support i18n and using constant variable MESSAGE_PATH for message resource bundle directory.

package org.joget.tutorial;
 
import org.joget.apps.app.service.AppPluginUtil;
import org.joget.apps.userview.model.UserviewMenu;
 
public class GanttChartMenu extends UserviewMenu {
    
    private final static String MESSAGE_PATH = "messages/GanttChartMenu";
 
    public String getName() {
        return "Gantt Chart Menu";
    }
    public String getVersion() {
        return "5.0.0";
    }
    
    public String getClassName() {
        return getClass().getName();
    }
    
    public String getLabel() {
        //support i18n
        return AppPluginUtil.getMessage("org.joget.tutorial.GanttChartMenu.pluginLabel", getClassName(), MESSAGE_PATH);
    }
    
    public String getDescription() {
        //support i18n
        return AppPluginUtil.getMessage("org.joget.tutorial.GanttChartMenu.pluginDesc", getClassName(), MESSAGE_PATH);
    }
 
    public String getPropertyOptions() {
        return AppUtil.readPluginResource(getClassName(), "/properties/ganttChartMenu.json", null, true, MESSAGE_PATH);
    }
 
    @Override
    public String getCategory() {
        return "Marketplace";
    }
    @Override
    public String getIcon() {
        //sorry, i am reuse the icon of other plugin here
        return "/plugin/org.joget.apps.userview.lib.HtmlPage/images/grid_icon.gif";
    }
    
    @Override
    public boolean isHomePageSupported() {
        return true; // Can use as first page of the userview
    }
    
    @Override
    public String getDecoratedMenu() {
        return null; // using default
    }
    @Override
    public String getRenderPage() {
        throw new UnsupportedOperationException("Not supported yet."); 
    }
}

Then, we have to do a UI for admin user to provide inputs for our plugin. In getPropertyOptions method, we already specify our Plugin Properties Options definition file is locate at "/properties/ganttChartMenu.json". Let us create a directory "resources/properties" under "gantt_chart_menu/src/main" directory. After create the directory, create a file named "ganttChartMenu.json" in the "properties" folder.

In the properties definition options file, we will need to provide options as below. Please note that we can use "@@message.key@@" syntax to support i18n in our properties options.

After done the properties option to collect input, we can work on the main method of the plugin which is getRenderPage method.

c. Manage the dependency libraries of your plugin

Our plugin is using javax.servlet.http.HttpServletRequest and javax.servlet.http.HttpServletResponse class, so we will need to add jsp-api library to our POM file.

<!-- Change plugin specific dependencies here -->
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jsp-api</artifactId>
    <version>2.0</version>
</dependency>
<!-- End change plugin specific dependencies here -->

d. Make your plugin internationalization (i18n) ready

We are using i18n message key in getLabel and getDescription method. We also used i18n message key in our properties options definition as well. So, we will need to create a message resource bundle properties file for our plugin.

Create directory "resources/messages" under "gantt_chart_menu/src/main" directory. Then, create a "GanttChartMenu.properties" file in the folder. In the properties file, let add all the message keys and its label as below.

e. Register your plugin to Felix Framework

We will have to register our plugin class in Activator class (Auto generated in the same class package) to tell Felix Framework that this is a plugin.

    public void start(BundleContext context) {
        registrationList = new ArrayList<ServiceRegistration>();
        //Register plugin here
        registrationList.add(context.registerService(GanttChartMenu.class.getName(), new GanttChartMenu(), null));
    }

f. Build it and testing 

Let build our plugin. Once the building process is done, we will found a "gantt_chart_menu-5.0.0.jar" file is created under "gantt_chart_menu/target" directory.

Then, let upload the plugin jar to Manage Plugins. After upload the jar file, double check the plugin is uploaded and activated correctly.

8. Take a step further, share it or sell it

You can download the source code from .

To download the ready-to-use plugin jar, please find it in http://marketplace.joget.org/.