Frequently Asked Questions about launch conditions

How do I stop the installation if a file was not found?

First you should create a File Search in the Search page. After that, the property of the search can be used as a custom launch condition. For example, if the property of the search is RESULT_PROPERTY, the launch condition can look like this:

RESULT_PROPERTY

The above condition is evaluate to "true" (the installation continues) when the search found the file. Please note that this approach can also be applied for registry entries, folders, INI files and Components.

How do I stop the installation if an older product was found?

For this you can use the OLDPRODUCTS property in the Custom Launch Conditions tab of the "Prerequisites" page. The OLDPRODUCTS property is set when an older product is found, so the launch condition would look like this:

(NOT OLDPRODUCTS)

The above condition is evaluated to "true" (the installation continues) when no older versions of the package was found.

How do I pass the values of ScreenX and ScreenY from Wizard Dialogs Stage to Install Execution Stage?

You can follow these steps:

  • go to the Install Parameters page and create two public properties, SCREEN_X and SCREEN_Y, initialised with 0
  • go to the Custom Actions page
  • here you will add two "Set installer property" custom actions before "Searches" action group in the Wizard Dialogs Stage; these are used to save the values of the ScreenX and ScreenY properties in the SCREEN_X AND SCREEN_Y properties
  • add another two "Set installer property" custom actions before "Searches" action group in the Install Execution Stage; these are used to restore the ScreenX and ScreenY properties values from SCREEN_X and SCREEN_Y properties

For example, the custom action which saves the value of the private property ScreenX can be configured like this:

Property Name:   SCREEN_X
Formatted text: [ScreenX]

The custom action which restores the value of the private property ScreenX can be configured like this:

Property Name:   ScreenX
Formatted text: [SCREEN_X]