Hello World!

Compiling

To compile the example:

• Launch EiffelStudio.
• Click Add project
• Browse to $ISE_EIFFEL\examples\wel\hello\.
• Choose hello.ecf
• Choose the location where the project will be compiled, by default the same directory containing the configuration file.
• Click OK.

Running

After you launch the sample, You should see a window displayed as illustrated above. You will have full control over the window, and the program will quit when you close the window.

Under the Hood

MAIN_WINDOW inherits WEL_FRAME_WINDOW. In this example, we have redefined on_paint as shown below: on_paint (paint_dc: WEL_PAINT_DC; invalid_rect: WEL_RECT) --Draw a centered text do paint_dc.draw_centered_text("Hello, World!", client_rect) end

Note: If you look at MAIN_WINDOW, you will see that it contains many features. However, nearly all of these are features are inherited from WEL_FRAME_WINDOW.

This sample contains the following classes:

• HELLO_DEMO
• MAIN_WINDOW

See Also:
Tutorial Step3
Common message hooks