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PDF Annotations

Annotations

When developing your own custom UI, you may wish to support the creation of annotations, including drawing, adding notes and highlighting text on a PDF document.

Draw Mode

Turning on drawing is as simple as setting the annotating mode to MuPDFDKAnnotatingMode_Draw against your MuPDFDKBasicDocumentViewController instance. To turn off drawing mode just set the annotating mode to MuPDFDKAnnotatingMode_None against your MuPDFDKBasicDocumentViewController instance.

The following code toggles draw mode on and off and might serve as the handler for one of the buttons in your UI.

if basicDocVc.annotatingMode == MuPDFDKAnnotatingMode_Draw {
    basicDocVc.annotatingMode = MuPDFDKAnnotatingMode_None
} else {
    basicDocVc.annotatingMode = MuPDFDKAnnotatingMode_Draw
}

When Draw Mode is enabled, the user can draw an ink annotation with the selected line thickness and color. When Draw Mode is then disabled, the annotation is saved to the document.

Line Thickness

To set & get line thickness, access the inkAnnotationThickness value as a CGFloat.

basicDocVc.inkAnnotationThickness = 10

Line Color

To set & get line color, access the inkAnnotationColor value as a UIColor.

basicDocVc.inkAnnotationColor = .green

Note Mode

To turn on note mode set the annotating mode to MuPDFDKAnnotatingMode_Note against your MuPDFDKBasicDocumentViewController instance. To save the note set the annotating mode to MuPDFDKAnnotatingMode_None.

basicDocVc.annotatingMode = MuPDFDKAnnotatingMode_Note

Highlighting

To turn on highlighting set the annotating mode to MuPDFDKAnnotatingMode_HighlightTextSelect against your MuPDFDKBasicDocumentViewController instance. When in text-highlighting mode, the document view will allow the user to create a text highlight by dragging across text, whereupon the mode will revert back to MuPDFDKAnnotatingMode_None, leaving a newly created annotation selected. The selected annotation will show drag handles which the user can use to adjust it.

basicDocVc.annotatingMode = MuPDFDKAnnotatingMode_HighlightTextSelect

Note

Highlight mode will only affect the actively selected text before the mode is activated.

De-selecting Annotations

Essentially all annotations are treated the same as simply selections once they have been selected by a user. This selection can then be cleared (de-selected) by calling the clearSelection() method against the MuPDFDKDoc instance within MuPDFDKBasicDocumentViewController.

let myDoc:MuPDFDKDoc? = basicDocVc?.session.doc as! MuPDFDKDoc
myDoc?.clearSelection()

Without an annotation being currently selected, calling clearSelection() will have no effect.

Deleting Annotations

Selections can be removed (deleted) by calling the deleteSelectedAnnotation() method against the MuPDFDKDoc instance within MuPDFDKBasicDocumentViewController.

func deleteDocumentSelection() {
    let myDoc:MuPDFDKDoc? = basicDocVc?.session.doc as! MuPDFDKDoc
    myDoc?.deleteSelectedAnnotation()
}

Without an annotation being currently selected, calling deleteSelectedAnnotation() will have no effect.

Author

To set the author name for subsequent annotation creations, an application developer should set the documentAuthor property to the required string value within the MuPDFDKDoc instance.

func setAuthor(name:String) {
    let myDoc:MuPDFDKDoc? = basicDocVc?.session.doc as! MuPDFDKDoc
    myDoc?.documentAuthor = name
}

Targetting document areas

Sometimes in order to focus an annotation, or to suggest an area to annotate, a developer may wish to highlight areas in a document and/or jump to a specific area of interest in a document. There are two API calls available to assist with this.

Outlining an area

To draw outlines on a document page use outlineArea.

basicDocVc.session.doc.outlineArea(<rect>, onPage: <page>)

Showing an area

To show an area on a document page use showArea.

basicDocVc.showArea(<rect>, onPage: <page>)

This software is provided AS-IS with no warranty, either express or implied. This software is distributed under license and may not be copied, modified or distributed except as expressly authorized under the terms of that license. Refer to licensing information at artifex.com or contact Artifex Software Inc., 39 Mesa Street, Suite 108A, San Francisco CA 94129, United States for further information.

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