HelloWorld: +A simple GUI application with a single view

Design and implementation

This application consists +of 4 classes:

Application class derived +from CEikApplication.
Document class derived +from CEikDocument.
AppUi class derived +from CEikAppUi.
AppView class derived +from CCoeControl.

E32Main() marks the entry point to the example. +It calls EikStart::RunApplication() to create a new application +instance. The UI framework then calls CExampleApplication::AppDllUid() to +obtain the application's UID. The UID returned must match the second value +defined in the project definition file.

Once the application is created, +the UI framework calls CExampleApplication::CreateDocumentL() to +create an instance of the document class. CreateDocumentL() internally +calls the constructor of the document class and passes the supplied reference +to the constructor initialisation list. The document has no real work to do +in this simple GUI application.

As soon as the document has been created +the UI framework creates an instance of the application UI (appUI). The appUI +class is an instance of a CEikAppUi -derived class and +this class takes care of user interaction.

AppUI creation uses two +phase construction where first CExampleDocument::CreateAppUiL() is +called and then the framework calls the second phase constructor of the appUI +class. CExampleAppUi::ConstructL() creates and owns the view. +User commands are handled by the CExampleAppUi::HandleCommandL() method.

The +app view class is used to draw the view. The view in this example consists +of a simple outline rectangle with text drawn in the middle.

The example +contains a resource file HelloWorld.rss which defines +resource information. This includes a menubar with four menu items, an icon +and caption.

HelloWorld.hrh defines the menu +command IDs and HelloWorld.pkg file is the source file +used for installation file (SIS file) generation.

Building and configuring

Steps to build the example:

You can build the example +from your IDE or the command line.

If you use an IDE, import the bld.inf file +of the example into your IDE, and use the build command of the IDE.

If +you use the command line, open a command prompt, and set the current directory +to the source code directory of the example. You can then build the example +with the SBSv1 build tools with the following commands:

bldmake +bldfiles

abld build

How to use bldmake and How to use abld describe +how to use the SBSv1 build tools.
For the emulator, the +example builds an executable called helloworld.exe in +the epoc32\release\winscw\<udeb or urel>\ folder.