Customizing PDF measurement tool in Android

By default, creating and editing measurement annotations in the drop-in components DocumentActivity and PdfViewCtrlTabHostFragment2 are automatically enabled unless disabled using ToolManagerBuilder. You can learn more about configuring ToolManager here .

To create a measurement annotations, tap and hold on an area of the PDF without any text or annotations to bring up the long-press quick menu. Then find a group called Measure in the overflow menu.

There are three measurement tools:

• Distance: RulerCreate
• Perimeter: PerimeterMeasureCreate
• Area: AreaMeasureCreate

Snapping is useful when you want to precisely place annotations in documents by snapping them to lines & objects. The point snapping API can be used to easily place annotations to the exact location.

This is disabled by default and can be enabled as follows:

mToolManager.SetSnappingEnabledForMeasurementTools(true);

The Calibrate menu option for measurement annotations allows you to determine a PDF's scale, enabling accurate measurements.