Compare files with overlay

Apryse SDK allows you to compare files visually using overlays.

Android

Overlay PDFs to find differences in Xamarin.Android

This tutorial only applies to Xamarin.Android. See Xamarin.iOS equivalent here .

You can visually compare pages. This resolution independent comparison allows you to quickly spot differences between pages.

There are two main ways to integrate the out-of-box UI components in your application:

1. Standalone activity
2. Comparison options dialog

Standalone activity

The DiffActivity is a standalone component that handles from picking two files to generating the comparison result.

1. Define the activity

** Storage Permission **

Please follow the latest Android best practices and guidelines outlined here

<activity android:name="com.pdftron.pdf.controls.DiffActivity" android:configChanges="keyboardHidden|orientation|screenSize|screenLayout|smallestScreenSize" android:theme="@style/PDFTronAppTheme" android:windowSoftInputMode="adjustPan" />

1. Show the activity

DiffActivity.Open(this);

Comparison options dialog

If you have your own viewer already and only want to show the comparison options in your application, the DiffOptionsDialogFragment can be used.

public void Show(Context context, FragmentManager fragmentManager, List<Android.Net.Uri> files)
{
    var fragment = pdftron.PDF.Dialog.Diffing.DiffOptionsDialogFragment.NewInstance(
        files[0], files[1]
    );
    fragment.SetStyle((int)DialogFragmentStyle.Normal, Resource.Style.PDFTronAppTheme);
    fragment.DiffOptionsConfirmed += (sender, e) =>
    {
        CompareFiles(context, files, e.Color1, e.Color2, e.BlendMode);
    };
    fragment.Show(fragmentManager, "diff_options_dialog");
}

where compareFile is:

private void CompareFiles(Context context, List<Android.Net.Uri> files, int color1, int color2, int blendMode)
{
    Android.Net.Uri uri = pdftron.PDF.Dialog.Diffing.DiffUtils.CompareFilesImpl(context, files, color1, color2, blendMode);
    // do something with the output
}

AsyncTask pattern can be used instead of Disposable pattern if desired.

iOS

Overlay PDFs to find differences in Xamarin.iOS

This tutorial only applies to Xamarin.iOS. See Xamarin.Android equivalent here .

The Apryse SDK provides powerful file comparison functionality. An example of this capability is shown below by comparing two PDF pages and highlighting the difference between them in red.

File 1	File 2	Difference

Show a file comparison view controller

The PTDiffViewController class shows a control to select two documents and create a new file showing the visual difference between them with customizable colors.

The file comparison control is part of the Tools library, so make sure you have added the Tools library to your project.

// Initialize a file comparison view controller.
var diffController = new PTDiffViewController();

diffController.DidCreateDiffFileAtURL += (sender, e) =>
{
    // Handle created diff file.
};

var navigationController = new UINavigationController(diffController);
if (!UserInterfaceIdiomIsPhone)
{
    navigationController.ModalPresentationStyle = UIModalPresentationStyle.Popover;

    navigationController.PopoverPresentationController.SourceView = btn;
    navigationController.PopoverPresentationController.SourceRect = btn.Bounds;
}

this.PresentViewController(navigationController, true, null);

The diff view controller must be pushed onto a navigation controller's stack before being shown.

Retrieving the file comparison output.

The PTDiffViewController creates an output file showing the visual difference between the two documents in a temporary directory and returns an NSURL with the file's location via a delegate method. To save and display the file, you must conform to the PTDiffViewControllerDelegate protocol.

File comparison sample code

The following sample code demonstrates how to use PDFNet to generate a document displaying the visual difference between two PDF pages:

// Xamarin sample code coming soon