Rotate a page

There are two options to rotate a page. First is using a UI component that can rotate at 90 degree angles. Second is an API guide to programmatically rotate a page.

UI component

Rotate document pages in Android

The RotateDialogFragment allows users to rotate pages of the opened document by 90, 180 and 270 degrees. It also displays a thumbnail of the current page at the selected rotation angle.

Show rotate page dialog

To show a rotate pages dialog in your activity, create a new instance of RotateDialogFragment by calling newInstance() and setting the PDFViewCtrl:

Java

private PDFViewCtrl mPdfViewCtrl;
// ...
public void showRotateDialog(FragmentManager fragmentManager) {
    RotateDialogFragment.newInstance()
                        .setPdfViewCtrl(mPdfViewCtrl)
                        .show(fragmentManager, "rotate_pages_dialog");
}

Kotlin

private var mPdfViewCtrl: PDFViewCtrl? = null
// ...
fun showRotateDialog(fragmentManager: FragmentManager) {
    RotateDialogFragment.newInstance()
                        .setPdfViewCtrl(mPdfViewCtrl)
                        .show(fragmentManager, "rotate_pages_dialog")
}

API guide

API to programmatically rotate pages in Android

To rotate a page in a PDF document.

Java

PDFDoc doc = new PDFDoc(filename);

// Rotate the first page 90 degrees clockwise.
Page page = doc.getPage(1);
int originalRotation = page.getRotation();
int rotation;
switch (originalRotation)
{
  case Page.e_0:   rotation = Page.e_90;  break;
  case Page.e_90:  rotation = Page.e_180; break;
  case Page.e_180: rotation = Page.e_270; break;
  case Page.e_270: rotation = Page.e_0;   break;
  default:         rotation = Page.e_0;   break;
}
page.setRotation(rotation);

Kotlin

val doc = PDFDoc(filename)

// Rotate the first page 90 degrees clockwise.
val page = doc.getPage(1)
val originalRotation = page.getRotation()
val rotation = when (originalRotation)
{
  Page.e_0    -> Page.e_90
  Page.e_90   -> Page.e_180
  Page.e_180  -> Page.e_270
  Page.e_270  -> Page.e_0
  else        -> Page.e_0
}
page.setRotation(rotation)

About rotating pages

A page can be rotated clockwise, by 90 degrees, when displayed or printed. The Page.GetRotation() method returns the Page.Rotate enum specifying the current rotation. Similarly, Page.SetRotation() sets the current rotation.