function CreateExtractionPage(const ACaption, ADescription: String; const OnExtractionProgress: TOnExtractionProgress): ExtractionWizardPage;
Creates a wizard page to extract 7-Zip archives and show progress.
Set OnExtractionProgress to a function to be informed of progress, or nil otherwise.
Unlike the other types of wizard pages, progress pages are not displayed as part of the normal page sequence (note that there is no AfterID parameter). A progress page can only be displayed programmatically by calling its Show method.
Call the Show method to activate and show the page. When you're finished with it, call the Hide method to revert to the previous page.
Always put the Hide call inside the finally part of a try..finally language construct, as demonstrated in CodeDownloadFiles.iss. Not calling Hide will result in the wizard being permanently stuck on the progress page.
To add a new archive to extract, call the Add method. Always call the Clear method before adding the first file.
To start the extraction, call the Extract method. An exception will be raised if there was an error. Otherwise, Extract returns the number of archives extracted.
Set the ShowArchiveInsteadFile property to True to show the name of the archive which is being extracted to the user instead of the names of the files inside the archive.
See Extract7ZipArchive for other considerations and the definition of TOnExtractionProgress.
See CodeDownloadFiles.iss for an example of CreateDownloadPage which works very similar to CreateExtractionPage.
TExtractionWizardPage
Extract7ZipArchive
CreateOutputProgressPage