Wirelexsoft the visual IDE company

RPC Design in VistaFei: A Tutorial

Introduction

This tutorial shows how to design and use RPC designed in VistaFei.

It uses a simple application as an example. A login Dialog performs a Remote Call Procedure to authenticate user based on some hard-coded username and password.

The VistaFei project for this tutorial may be found here.

Assumptions

The reader is assumed familiar with creating and using Design Sheets in VistaFei.

The Application

The application consists of one UI Design Sheet (demo.GWTApp) which is also the entry point to the application, and one RPC Design Sheet demo.RPC. These two Design Sheets will be under the WXDesignFolder under project.

The demo.GWTApp contains a vertical panel with components to simulate a login screen.

The RPC is a simple authentication process

Generate Code

We can now generate code for these two Design Sheets, by either clicking on the G Tool in the Tool Bar or right clicking on Project then Wirelexsoft ->Generate Code.

After you generate code you get following source files.

Business Logic of Application

The demo.Java will create the necessary Login screen. The Code Generator will generate all needed code for this purpose.

The set of Classes generated for the RPC will have stubs, rather than full code, because we haven't specified how the authentication will be carried out yet.

There are two tasks for the developer.

1- Populate the Classes generated for the RPC based on the kind of service required,

2- Create the Business Logic for the Operation, i.e. create user-defined Java Classes to contain the Business Logic.

Populating Classes for RPC

In this example, the backend authentication is simulated, i.e. not real. The RPC Classes are populated to achieve this purpose. Screenshot below shows contents for Class shown in the screenshot above. For other Classes, you may find them in the Project Code.

User Defined Classes

For this application we created three Java Classes to allow for the Business Logic -we created a user-defined package com.wirelexsoft.rpc.client.login.

LoginController.java
LoginMapping.java
LoginShell.java

The screenshot below shows the code for one of these Classes. The others may be inspected in the Project Code.

Application Entry Point

demo.java is the Application Entry Point. We need to add code there to complete the application, as follows. Open demo.java and perform the following:

Step 1

Add the code below

// TODO 1
import com.wirelexsoft.rpc.client.login.*;

Step 2

Add Loginshell to

public class demo extends AbsolutePanel implements EntryPoint,ChangeListener,ClickListener,LoginShell{

Step 3

Add the code below

// TODO 3
private LoginController controller = new LoginController();
private LoginMapping mapping = new LoginMapping();

Step 4

Add the code below

// TODO 4
public void inBound() {
  btLogin.setEnabled(mapping.isEnabled());
  lbStatus.setText(mapping.getStatus());
}

public void outBound() {
  mapping.setUsername(txtUserName.getText());
  mapping.setPassword(txtPassword.getText());
}

public LoginMapping getMapping() {
  return mapping;
}

Building and Launching your application

When you build and launch your application you should get the following

End of Tutorial