Redacting PDFs in iOS Viewer

This guide covers how to redact a document via the built-in UI.

Creating Redactions via the User Interface

In addition to being able to create redactions programmatically, you can create and customize redactions via the UI PSPDFKit provides.

Adding a redaction to a document can be done by selecting the redaction tool on the annotation toolbar. This will enable the redaction mode and allow you to select the redaction area by either tapping on a word, dragging over some text, or dragging to create a rectangle over an arbitrary area. Depending on where the drag gesture started, either text selection or free-form selection is used until the gesture is complete. A redaction annotation will be created once you lift your finger.

Another way of creating a text redaction is by first selecting text and then tapping the redaction item on the menu. Note that when using the standard configuration, the redaction tool in the text selection menu is, by default, only shown in regular, horizontal-size class environments.

Once a redaction is added to the document, its properties and appearance can be customized via the annotation inspector.

Applying Redactions Via the User Interface

Once there are redactions in the document, a floating redaction info button is shown in the user interface view. Tapping this button reveals a UI for applying redactions in the document. Tapping the Redact Current Document button will overwrite the current document and remove the content in the area of the redaction annotations irreversibly. In the process of redacting the content, all redaction annotations are removed from the document. Additionally, any cached page images and indexed full-text search content will be removed so that none of the redacted content is referenced in any stale cache. The Redact Current Document button will only be visible if the current document is writable and not stored at a read-only location.

In case you want to keep the current document as is and only redact content in a new document, you can choose the Save Redacted Document As… option, which will allow you to pick a location where the new redacted document should be stored.

Note that there may be cases where this floating button is not always shown when opening a document with existing redactions, since this would require parsing the entire document upfront. It’s best to avoid this, since it can have some serious performance implications, especially with larger documents. You can manually trigger parsing the entire document by tapping the redaction tool in the annotation toolbar.

Previewing Redactions via the User Interface

Redactions can be previewed by tapping on the floating redaction info button. When flipping the Preview switch, all redaction annotations in a document will be rendered in their redacted state appearance (as opposed to the marked state that’s otherwise always shown by default). This can be done without having any content removed from the document; it’s just for previewing purposes, and the actual removal of the document content will only happen when using one of the redaction buttons.

Custom Redaction UI

If you want to customize the UI to preview and apply redactions, you can disable the floating redaction info button in the user interface view via shouldShowRedactionInfoButton. Then you can roll your own UI to indicate uncommitted redactions and handle previewing and applying redactions in your own way instead.

Redacting Graphic Objects Shared across Pages

Graphic objects — including images and vector graphics — can be reused across pages in a PDF. If a graphic object is redacted and reused, all instances of that graphic object will also be redacted.

This means that, for example, when you redact part of an image, the same part of the same image on another page will also be redacted. This is compatible with how Adobe Acrobat does it. A common example of this is if you have to redact a logo that is shown on each page.

Warning

Even if the images look exactly the same, they could be separate images and not be redacted the same. Always be careful and review the redacted document when you’re done.

Licensing

The following redaction features are part of the Redaction component that must be licensed separately. The following list describes the expected behavior if Redaction isn’t part of your license:

  • The redaction annotation toolbar button and text selection menu item will be hidden.

  • The floating redaction information button won’t be shown.

  • The annotation inspector for existing redaction annotations can’t be shown.

  • RedactionAnnotation can’t be created.

  • RenderOptions.drawRedactionsAsRedacted, applyRedactions(), and similar APIs won’t work or assert when used.