PDF highlight annotation blend mode menu in Swift for iOS

1
//
2
//  Copyright © 2019-2026 PSPDFKit GmbH. All rights reserved.
3
//
4
//  The Nutrient sample applications are licensed with a modified BSD license.
5
//  Please see License for details. This notice may not be removed from this file.
6
//
7

8
import PSPDFKit
9
import PSPDFKitUI
10

11
class BlendModeMenuForMarkupAnnotationsExample: Example {
12

13
    override init() {
14
        super.init()
15

16
        title = "Show Blend Mode menu item when selecting a highlight annotation"
17
        contentDescription = "Shows how to add the Blend Mode menu item in the highlight annotation selection menu."
18
        category = .annotations
19
        priority = 204
20
    }
21

22
    override func invoke(with delegate: ExampleRunnerDelegate) -> UIViewController {
23
        let document = AssetLoader.writableDocument(for: .welcome, overrideIfExists: false)
24
        document.annotationSaveMode = .embedded
25

26
        // Add highlight annotation if there isn't one already.
27
        let pageIndex: PageIndex = 0
28
        let highlights = document.annotationsForPage(at: pageIndex, type: .highlight)
29
        if highlights.isEmpty {
30
            let textParser = document.textParserForPage(at: pageIndex)!
31
            for word in textParser.words where word.stringValue == "PSPDFKit" {
32
                guard let range = Range<Int>(word.range) else {
33
                    continue
34
                }
35
                let highlightAnnotation = HighlightAnnotation.textOverlayAnnotation(with: [Glyph](textParser.glyphs[range]))!
36
                highlightAnnotation.color = .yellow
37
                highlightAnnotation.pageIndex = pageIndex
38
                document.add(annotations: [highlightAnnotation])
39
            }
40
        }
41
        let controller = BlendModeMenuForMarkupsViewController(document: document) {
42
            // Configure the properties for highlight annotations to show the blend mode menu item.
43
            var annotationProperties = $0.propertiesForAnnotations
44
            annotationProperties[.highlight] = [[.blendMode, .color, .alpha]] as [[AnnotationStyle.Key]]
45
            $0.propertiesForAnnotations = annotationProperties
46
        }
47
        return controller
48
    }
49
}
50

51
private class BlendModeMenuForMarkupsViewController: PDFViewController {
52
    override func viewDidAppear(_ animated: Bool) {
53
        super.viewDidAppear(animated)
54
        // Select the highlight annotation to show the Inspector menu.
55
        let pageView = self.pageViewForPage(at: 0)
56
        guard let highlightAnnotation = self.document?.annotationsForPage(at: pageIndex, type: .highlight).first else { return }
57
        pageView?.select(annotations: [highlightAnnotation], presentMenu: true, animated: true)
58
    }
59
}