Customize zoom options in the Flutter PDF viewer

Use the zoom API to control the zoom scale of a PDF page programmatically.

Zoom manually

Get NutrientController from the onControllerReady callback of NutrientDocumentView. Then use zoomToRect(pageIndex, rect) to zoom to an area of a page, and use getZoomScale(pageIndex) to read the current zoom level. Both methods support Android, iOS, and web. Refer to the Nutrient controller(opens in a new tab), zoom to rect(opens in a new tab), and get zoom scale(opens in a new tab) API references for details.

Zoom in to a page area

Use zoomToRect(pageIndex, Rect) to zoom in to a specific Rect on any page. For example, you can zoom to an annotation’s bounding box:

NutrientDocumentView(
  documentPath: documentPath,
  onControllerReady: (controller) async {
    final rect = Rect.fromLTWH(60.0, 700.0, 200.0, 80.0);
    await controller.zoomToRect(0, rect);
  },
)

Use getZoomScale to read the current zoom level of a page:

final scale = await controller.getZoomScale(0);

For more information about zooming, open zoom_to_rect_example in the Catalog app.

Disable zooming

To disable zooming, set maximumZoomScale to 1.0 on NutrientViewConfiguration before you create the view. Refer to the Nutrient view configuration(opens in a new tab) API reference for details.

NutrientDocumentView(
  documentPath: documentPath,
  configuration: const NutrientViewConfiguration(
    maximumZoomScale: 1.0,
  ),
)