Tutorial - Implementing a Splash Screen

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What is a Splash Screen?

A splash screen is a form that is displayed when an application is first starting to inform the user that the program is actually doing something even though you can not see this. Like connecting to database, creating many forms, etc. The most basic splash screen is just an image that appears in the centre of the screen when the application is loading and then disappears when it has loaded.

Why use a Splash Screen?

A Splash Screen adds a professional touch to an application without adding an excessive amount of work, for shareware programs it is also a good place to remind users to register the package.

How To

The first stage is to produce the form that you wish to display. You can have anything that you like on this, with the norm being an image and some text underneath it, indicating what stage of loading the application is at. Create a new form, and change the following properties:

Property Value Description
Name SplashV This can be any name that you like, but for the purpose of this tutorial it is easier if we have a name to refer to.
Position poScreenCenter So the splash screen appears in the centre of the screen at start up
BorderStyle bsNone We do not wish the user to be able to move or close the splash screen

Next add a Label to the form aligned alBottom, and change its caption property to 'My Application Loading' or whatever you prefer Also add an image to the form and align this alClient. Change the picture property of the image to whatever image you wish displayed. Now is a good time to resize the form, so that the image and caption fit in as you want them. If necessary you can change the autosize property of the image to true, so that your image fills the entire form (apart from the caption area) but make sure the image still looks good when it has been re sized.

You are now at the stage where you want to be adding the splash screen to your application. Add the SplashV form as you would any other (Add to project from the file menu) You now need to modify the dpr file so that the form is not auto created. This is done by removing the command

  Application.CreateForm(TSplashV,SplashV);

from the dpr file of your application. Next you have to modify the dpr file so that SpashV is created and then displayed, and also before the application runs the splash screen is hidden and destroyed. This is done by adding the following lines straight after the begin of the dpr file:

(* Create the splash Screen *) 
SplashV := TSplashV.Create(Application); 
(* Show the splash Screen *) 
SplashV.show;
(* Update the splash Screen so that all components on it are 
   visible *) 
SplashV.update;

Finally before the application.run statement in the dpr file add the following:

(* Hide the splash screen from the user *)
SplashV.hide;
(* Free any resources that it used*)
SplashV.free;

If you wish to modify the splash screen to inform the user of the progress of the application loading, add the following sort of lines in the relevant section of the dpr file:

(* Change the caption to indicate connecting to the database *) 
SplashV.label1.caption:=' Connecting to the Database;
(* Update the splash Screen so that all components on it are 
   visible and up to date *) 
SplashV.update;

Conclusion

You should now have an application complete with splash screen, I will leave it to you to modify this to suit your needs e.g. checking if the user has registered you package and displaying a message accordingly, changing the image if your application takes a long time to start up, etc.

Hint

Whilst debugging you may find the splash screen obscures you code if you are stepping through it at start up. This can be resolved by adding a parameter to your program to indicate not to show the splash screen

e.g. 
if not(ParamStr(1) = 'ns') then
begin
(* Code to display splash screen here *)
end;

NB Make sure that you do not access the splash screen later if it has not been created

 


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