Interactive Annotations using Python

This article shows how to work with interactive annotations in PDF documents using Aspose.PDF for Python via .NET.

The example script demonstrates several common workflows:

  • add a link annotation to existing text
  • get link annotation rectangles from a page
  • delete link annotations
  • create navigation buttons
  • create a print button

This example searches the first page for the text fragment "file" and places a clickable link annotation over the matching text area. When the user clicks the annotation, the PDF opens the specified web address.

Load the document and find the target text

Create a Document object and use TextFragmentAbsorber to search for the text that will become interactive.

document = ap.Document(infile)
text_fragment_absorber = ap.text.TextFragmentAbsorber("file")

document.pages[1].accept(text_fragment_absorber)
phone_number_fragment = text_fragment_absorber.text_fragments[1]

Build a LinkAnnotation using the rectangle of the matched text fragment and assign a URI action to it.

link_annotation = ap.annotations.LinkAnnotation(
    document.pages[1], phone_number_fragment.rectangle
)
link_annotation.action = ap.annotations.GoToURIAction("https://www.aspose.com")

Add the annotation and save the PDF

Append the annotation to the page and save the updated file.

document.pages[1].annotations.append(link_annotation)
document.save(outfile)

Complete example

def link_add(infile, outfile):
    document = ap.Document(infile)
    text_fragment_absorber = ap.text.TextFragmentAbsorber("file")

    document.pages[1].accept(text_fragment_absorber)
    phone_number_fragment = text_fragment_absorber.text_fragments[1]

    link_annotation = ap.annotations.LinkAnnotation(
        document.pages[1], phone_number_fragment.rectangle
    )
    link_annotation.action = ap.annotations.GoToURIAction("https://www.aspose.com")

    document.pages[1].annotations.append(link_annotation)
    document.save(outfile)

To inspect existing interactive links, filter the annotations collection on the first page and keep only items whose type is LINK. The sample then prints the rectangle for each matching annotation.

document = ap.Document(infile)
link_annotations = [
    a
    for a in document.pages[1].annotations
    if (a.annotation_type == ap.annotations.AnnotationType.LINK)
]

Read the annotation rectangles

Loop through the filtered annotations and print the coordinates of each link area.

for link_annotation in link_annotations:
    print(link_annotation.rect)

Complete example

def link_get(infile, outfile):
    document = ap.Document(infile)
    link_annotations = [
        a
        for a in document.pages[1].annotations
        if (a.annotation_type == ap.annotations.AnnotationType.LINK)
    ]

    for link_annotation in link_annotations:
        print(link_annotation.rect)

This workflow removes all link annotations from the first page and saves the cleaned PDF as a new file.

document = ap.Document(infile)
link_annotations = [
    a
    for a in document.pages[1].annotations
    if (a.annotation_type == ap.annotations.AnnotationType.LINK)
]
for link_annotation in link_annotations:
    document.pages[1].annotations.delete(link_annotation)

Save the updated document

document.save(outfile)

Complete example

def link_delete(infile, outfile):
    document = ap.Document(infile)
    link_annotations = [
        a
        for a in document.pages[1].annotations
        if (a.annotation_type == ap.annotations.AnnotationType.LINK)
    ]

    for link_annotation in link_annotations:
        document.pages[1].annotations.delete(link_annotation)

    document.save(outfile)

Widget Annotation

Add Navigation Button

Navigation buttons are useful in multi-page PDFs when you want readers to move between pages without using the viewer interface. This sample adds Previous Page and Next Page buttons to each page.

Define button settings

Store the button captions, positions, and predefined actions in a simple configuration list.

button_config = [
    ("Previous Page", 120.0, ap.annotations.PredefinedAction.PREV_PAGE),
    ("Next Page", 230.0, ap.annotations.PredefinedAction.NEXT_PAGE),
]

Load the PDF and ensure multiple pages exist

The sample opens the source document and adds one more page so the navigation actions have at least two pages to work with.

document = ap.Document(infile)
document.pages.add()

Create the buttons on each page

For every page, create a ButtonField, set its text and colors, assign a predefined navigation action, and add it to the form.

for page in document.pages:
    for name, x_pos, action in button_config:
        rect = ap.Rectangle(x_pos, 10.0, x_pos + 100, 40.0, True)
        button = ap.forms.ButtonField(page, rect)
        button.partial_name = name
        button.value = name
        button.characteristics.border = ap.Color.red.to_rgb()
        button.characteristics.background = ap.Color.orange.to_rgb()
        button.actions.on_release_mouse_btn = ap.annotations.NamedAction(action)
        document.form.add(button)

Save the result

document.save(outfile)

Complete example

def navigation_buttons_add(infile, outfile):
    button_config = [
        ("Previous Page", 120.0, ap.annotations.PredefinedAction.PREV_PAGE),
        ("Next Page", 230.0, ap.annotations.PredefinedAction.NEXT_PAGE),
    ]

    document = ap.Document(infile)
    document.pages.add()

    for page in document.pages:
        for name, x_pos, action in button_config:
            rect = ap.Rectangle(x_pos, 10.0, x_pos + 100, 40.0, True)
            button = ap.forms.ButtonField(page, rect)
            button.partial_name = name
            button.value = name
            button.characteristics.border = ap.Color.red.to_rgb()
            button.characteristics.background = ap.Color.orange.to_rgb()
            button.actions.on_release_mouse_btn = ap.annotations.NamedAction(action)
            document.form.add(button)

    document.save(outfile)

Add Print Button

This example creates a new one-page PDF and places a print button near the top of the page. Clicking the button triggers the predefined print action in a compatible PDF viewer.

Create a new PDF and add a page

document = ap.Document()
page = document.pages.add()

Create and configure the button

Define the button rectangle, create the ButtonField, set its caption, and attach the print action.

rect = ap.Rectangle(72, 748, 164, 768, True)

print_button = ap.forms.ButtonField(page, rect)
print_button.alternate_name = "Print current document"
print_button.color = ap.Color.black
print_button.partial_name = "printBtn1"
print_button.value = "Print Document"
print_button.actions.on_release_mouse_btn = ap.annotations.NamedAction(
    ap.annotations.PredefinedAction.FILE_PRINT
)

Set border and background styles

The sample defines a solid border and applies custom colors to make the button visible in the document.

border = ap.annotations.Border(print_button)
border.style = ap.annotations.BorderStyle.SOLID
border.width = 2
print_button.border = border

print_button.characteristics.border = ap.Color.blue.to_rgb()
print_button.characteristics.background = ap.Color.light_blue.to_rgb()

Add the button and save the PDF

document.form.add(print_button)
document.save(outfile)

Complete example

def print_button_add(infile, outfile):
    document = ap.Document()
    page = document.pages.add()

    rect = ap.Rectangle(72, 748, 164, 768, True)

    print_button = ap.forms.ButtonField(page, rect)
    print_button.alternate_name = "Print current document"
    print_button.color = ap.Color.black
    print_button.partial_name = "printBtn1"
    print_button.value = "Print Document"
    print_button.actions.on_release_mouse_btn = ap.annotations.NamedAction(
        ap.annotations.PredefinedAction.FILE_PRINT
    )

    border = ap.annotations.Border(print_button)
    border.style = ap.annotations.BorderStyle.SOLID
    border.width = 2
    print_button.border = border

    print_button.characteristics.border = ap.Color.blue.to_rgb()
    print_button.characteristics.background = ap.Color.light_blue.to_rgb()

    document.form.add(print_button)
    document.save(outfile)