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 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)