useAlternativeFitScaleAsMinScale property
If true, the minimum scale is set to the calculated PdfViewerController.alternativeFitScale.
If the minimum scale is small value, it makes many pages visible inside the view and it finally renders many pages at once. It may make the viewer to be slow or even crash due to high memory consumption. So, it is recommended to set this to false if you want to show PDF documents with many pages.
Implementation
final bool useAlternativeFitScaleAsMinScale;