Set cache fails and succeeds randomly

I am trying to save a bitmap to a pdf page. SetCache is failing but sometimes succeeds. Is there a specific order I need to call setCache? What is setcache calling to make sure it succeeds?

Global was messing with the cache, it works.

thanks

I thought i fixed it, but the problem is still happening. Setcache returns false and I cannot save a bitmap annotation. Adding the annotation with addbitmapannotation returns true, but the annotation count is 0.

do not share 1 file as cache file to 2 document objects.
it is important. and invoke Document.close() to release cache file.

I do not share files. I open multiple documents in a view pager. The only sharing is Global. Each has its own PDFReader and Document, but i have found that sometimes calling setcache would fail, but if i closed and reopened the app, setcache would succeed. I always invoke document.close when the view pager destroys the fragment the pdfreader is in.

I am using

mDocument.SetCache(Global.tmp_path + "/" + String.valueOf(mPageNumber) + "/temp.dat");

This is working mDocument.SetCache(Global.tmp_path + "/" + String.valueOf(mPageNumber) + "temp.dat");

Im assuming setcache does not create directories, though maybe it should.