Android Library Project and its usage

"Android Library projects contain shareable Android source code and resources that you can reference in Android projects. This is useful when you have common code that you want to reuse. Library projects cannot be installed onto a device, however, they are pulled into the .apk file at build time." 

When creating a new Android project you can mark a project as ‘Library’ project. This will create a project that can be shared/used in multiple projects. You cannot run/install the library project stand alone instead you have to reuse it in Android project.

How to mark a project as library:

Create a new Android project that will use the library project. Library project can be added as reference as follows:

• Android Project > Properties > Android (left option) > Library (bottom right pane) > Add

  

                       

Click ‘Apply’ > ‘OK’

• To use the library class activities in android project, 'import' the library references where ever you are using library files.

• To launch the library activity you should have that activity listed in your Android project 'AndroidManifest.xml'.

• Don’t make files (Layouts, Classes, XML’s) with the same name in main and library projects. This can cause problems at run time. What I have noticed is that if you have same name layouts in both projects the library layout got overridden and parent layout will be used.

rizzz86

Manipulating PDF document using iText library

There are several libraries that can be used to manipulate a PDF document like PDFBox, iText, PDFClows etc. I also have to do some PDF manipulation stuff and I decided to go with iText. I choose iText because it supports low level PDF manipulation, its community is very strong, lots of helping hands are available and it is also open source and available in both Java and C#.

iText allows you to create a PDF doument, add content in it, update content and save it. I have tried following basic features so far and found it really interesting:

• With low level support one can add a text chunk, paragraph, phrase, link, chapter, section, image, set text color and other attributes into the document. 
• You can also create a table/grid inside a PDF document and play with each cell of the table.
• It is also easy to read an existing PDF document. You can retrieve existing information related to document and pages.
• Using iText one can also fill up an empty PDF template.
• It allows to set javascript in a PDF document to make a document interactive. Document can be also be navigated to a particular page. Creating bookmarks, annotations and triggering javascirpt from a button can also be done using iText.
• Document can also be password encrypted to allow/disallow certain actions that can be done the document.
• Whole PDF document can also be signed using a certificate to make the document secure.

There is also a book on how to play with PDFs using iText in Action. He is the author of iText in Action and is very supportive on stackoverflow. I also have some questions regarding iText on stackoverflow on this link.

rizzz86