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androidscrollcoordinate-systemspdftronpdfnet

Set PDFViewCtrl scroll to an absolute position in the document

I'm using the Android version of PDFNet 6.5.0.

I need to set the vertical scroll of the PDFViewCtrl to an absolute point in the pdf, expressed in PDF Canvas coordinates.

For example, say that I want to zoom to the middle of the second page.

I could get the y coordinate, in PDF Canvas position like:

int y = doc.getPage(1).getPageHeight() + (doc.getPage(2).getPageHeight() / 2)

How could I scroll to the y position?

I'm trying to do it with PDFViewCtrl#setVScrollPos(), but I don't know how to convert y to a valid parameter for this method.

Solution

  • Have you tried to use PDFViewCtrl#scrollTo(int, int)?

    i.e. first convert points from PDF space to canvas space(PDFViewCtrl#convPagePtToCanvasPt), then scrollTo the position.