Annotation RenderToBmp is not working

I have to show all annotations from current page in to listview.
I am trying to render annotation to bitmap object using RenderToBmp(bitmap). Method returns true after render but annotation is not rendered on bitmap.
Bitmap bitmap = Bitmap.createBitmap(100, 100, Config.ARGB_8888);
bitmap.eraseColor(0xFFFFFFFF);
annot.RenderToBmp(bitmap);
ivImage.setImageBitmap(bitmap);
PDF sdk : 3.4

I suggest you to try creating a bmp container like that below

float[] r = m_annot.GetRect();
int w = Math.abs((int) (r[3] - r[0]));
int h = Math.abs((int) (r[2] - r[1]));
Bitmap bitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
bitmap.eraseColor(0xFFFFFFFF);
m_annot.RenderToBmp(bitmap);

We've tried with a bunch of different annotations and wasn't experiencing the issue you're saying.