Develop Reference

Protect tab/range in Google Sheet via Drive API for Java

I have an application that creates Google spreadsheets through Java code. I have looked through the permissions section in Google Drive API and I'm going to give edit access to anyone with the link.
In certain sheets I need to make only one tab 'view only', i.e. protect that tab. Is it possible to do this via Drive API?
Is it possible to give a name to the current version of the file via Drive API?

Give Java application access to specific Google Spreadsheet

How do I give access to one specific Google Spreadsheet to a Java (or Clojure) application?
Read only access is fine. My idea is to keep data in a Spreadsheet that I and some collaborators can edit, instead of in a database. Is Oauth2 needed in this case, or is there an easier way to accomplish this?

Your post intrigues me, simply because I have been using Google Spreadsheet as my "simple centralized database" that I can query against from all my machines. That said, my approach was very rudimentary (written in ~2009) because I only read the published CSV link and I don't do any write on the spreadsheet from my app.
After googling around, it seems like this is doable. Have you checked out this link? https://developers.google.com/google-apps/spreadsheets/ It seems like you can use OAuth to grant/check access before performing read/write on the spreadsheet. And they have examples in both Java and .Net to accomplish that.

Android Open and Save String to/from Google Drive SDK

I have read allot about Google drive integration and I want to save STRING into Google drive and also to retrieve, I have used this demo but it is giving me errors.
please anyone provide me demo for my requirement

First, let's clear the confusion here. Your original question refers to a demo that uses the original RESTful API (aka DriveSDKv2), where Simple Plan mentions a different API, the new Google Drive Android API (GDAA).
The GDAA, does not have the full functionality at the moment, but it can be combined with the DriveSDKv2 to supplement what's missing (delete, description, indexable, ...). On the other hand, the GDAA takes care of all synchronization, offline and caching issues. You just create, retrieve, update the files as if they were local and the magic of up/down synchronization is left to GDAA. And the missing functionality is promised soon.
If you decide to dive into GDAA, there are 3 demos available on Github at the moment:
quick start
full-blown demo
trivial example with wrapper class to create, retrieve files/folders
Both demo and trivial examples have the create functionality with a text written to a file. If you pull any of them and step through, you'll get the idea.

How to open and edit a file(doc,pdf,excel etc) in browser window using zk?

I have a application which is created on ZK Framework , i want to give user a functionality where user can open a saved file in edit mode and then again saved the changed in database can any one know which API can help me to do this?

You could use Google Apps to do so and set Google Docs to edit your DOC, PDF or even XLS extension files. For more help on setting it up, feel free to ask again. :)

The problem you're posing doesn't have a simple answer, unfortunately.
There are two general approaches you could take..
The low hanging fruit is to provide an interface for the user to download a file and upload it after they make edits using whichever editing software they choose / is appropriate.
The other approach would be to provide a GUI to edit files. Regardless of the web framework you are using, this is a daunting task to say the least. As #userRandom mentioned, this is a large part of what Google Drive (formerly Google Docs) is attempting to solve.. but even Google's solution is not perfect and very much a work in progress.
I would strongly suggest evaluating the scope of your project before proceeding.
If you choose to move forward, consider a simple solution that works for .txt files. Then, consider how you might handle .doc files. Then, PDF files, XLS files, etc.
Folks here will be able to answer specific questions.

Share a piece of data between several Android apps

I am writing an SDK for Android that will be used by many different apps. Each app needs to know if there is a previous installation of another app that uses the SDK; the first one will create a random id (a cookie) and store it, all later apps have to read it and reuse it. Note that the cookie will be created anew for every device.
I have searched for a long time for the answer; please read thoroughly before answering because I have read lots of different StackOverflow answers and have scoured the internet reading random blogs; I have tried a lot of things but none worked (I will save you the links).
A ContentProvider is definitely overkill. Also it needs to intrude an app's AndroidManifest.xml, something I am trying to avoid.
Likewise for a service: needs to be defined in the AndroidManifest.xml, which I do not control and do not want to require changes to.
Using external storage would perhaps be an option, but I don't want to require additional permissions.
Using SharedPreferences directly with getSharedPreferences() does not work because apps can only access their own preferences.
I can get a common preferences object using createPackageContext(package, MODE).getSharedPreferences(). This would work beautifully if I had a main package and many clients of the data, but in fact I don't know the package of the app that will be installed first -- it can be any of them. I don't even have a list of package names to search. Passing a package name which has not been installed fails.
Following the approach above, I have tried to piggyback on some standard Android app which I can count on, and store my preferences there -- say:
createPackageContext(
"com.android.browser",
Context.CONTEXT_RESTRICTED)
.getSharedPreferences(
"GLOBAL_PREFS",
Context.MODE_WORLD_READABLE);
but it does not work: the error reads
Couldn't create directory for SharedPreferences file
/data/data/com.android.browser/shared_prefs/GLOBAL_PREFS.xml
So, to recap: I need to store a piece of data (a short string) in some standard location, so that any other app can go there and read it if present, and it should work if at all possible without doing any magic in the AndroidManifest.xml or requesting any permissions.
There probably isn't any perfect answer, so perhaps the best solution is to write to external storage; then so be it. To put things into context, apparently it is trivial to do this on iOS using a keychain, designed to store secure data.

Unfortunately there really isn't a great answer for this that I know of. You've come up with a pretty good outline of your options and the best way may well be with external storage.
Just to throw something out there, I suppose it's possible you could use a flat file with a fixed name and world readable (and possibly writable) permissions. You'd have to then iterate through all applications' directories and check for this known-named file in each folder and attempt to open it.
While this might work theoretically, consider the case where the app that contains the "cookie" is uninstalled. Then you're left cookie-less. You might want to create the cookie in every app, copying over the value of the previous cookies to new cookies.
I haven't actually tried this, but I imagine it should work.