This guide demonstrates how to display a PDF. To begin working with PDFTron SDK, you must have first added it to your project.

1. PDFTron must be initialized before using any PDFTron classes. This only needs to be done once. This is done as shown:

   For trial purposes PDFTron is available without the need for a license key, however a valid license key is required to use PDFTron in a production app. If you do not have a valid license key, please contact sales for a commercial license key.

   Your license key is confidential. Please make sure that it is not publicly available (e.g. in your public GitHub).

   PTPDFNet.initialize("<key-goes-here>")

2. At the top of your source file, import PDFNet and Tools.

   import PDFNet
   import Tools

3. The following shows how to create a document viewer, set the document to display, and present it on screen.

   // Create a PTDocumentViewController
   let documentController = PTDocumentViewController()
   
   // The PTDocumentViewController must be in a navigation controller before a document can be opened
   let navigationController = UINavigationController(rootViewController: documentController)
   
   // Open an existing local file URL.
   let fileURL: URL! = Bundle.main.url(forResource: "sample", withExtension: "pdf")
   
   documentController.openDocument(with: fileURL)
   
   // Show navigation (and document) controller.
   self.present(navigationController, animated: true, completion: nil)