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:

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   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 PTDocumentController
   let documentController = PTDocumentController()
   
   // The PTDocumentController 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)