Question

You can direct the installer to perform actions before a page is shown by using a <preShowPageActionList> section. The following example presents the user with information that stored in a registry key under Windows and in an environment variable under Linux.

<infoParameter>
        <preShowPageActionList>
          <registryGet>
         <variable>some_info</variable>
             <key>HKEY_LOCAL_MACHINE\SOFTWARE</key>
            <name>MYAPP</name>
            <ruleList>
              <compareText>
               <text>${platform_name}</text>
               <logic>equals</logic>
               <value>windows</value>
              </compareText>
            </ruleList>
         </registryGet>
         <setInstallerVariable>
           <name>some_info</name>
           <value>${env(SOMEINFO)}</value>
           <ruleList>
              <compareText>
               <text>${platform_name}</text>
               <logic>equals</logic>
               <value>linux</value>
              </compareText>
           </ruleList>
          </setInstallerVariable>
        </preShowPageActionList>
        <name>display_info</name>
        <title>License File Information</title>
        <explanation>This screen shows important information about licensing issues</explanation>
        <value>Important Information! Setup has detected the following : ${some_info}.
      In the following screen you will be asked to confirm the information or enter a new (...)</value>
</infoParameter>