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How to use same libraries on whole project?

I'm using many applications in one project like :
So i have some questions here, Application must implement iterated libraries ?
Assume i have com.android.support:appcompat in my "app" gradle and have the same one in my "opencv-java" gradle the apk will compiled with both libraries and double the size?
If no, then what happened in compiling process?
If yes, How i can avoid this, is there a way or some thing?
Update :
If i have libraries (e.g: "volley", "support" etc..) in my app "gradle" and also i used it in my open-cv "gradle", that's make me able to remove those libraries from app "gradle", it's seems that main app that used compile project(':another-app') in "gradle" can use another-app libraries, with codes and assets, every thing.

the apk will compiled with both libraries and double the size?
No.
then what happened in compiling process?
Well, one of two things:
If you use compile "com.android.support:appcompat-v7" consistently, Gradle will only use one copy of that dependency.
Your build could fail with an error message complaining about duplicate Java classes, stemming from the duplicate libraries. This would happen if you are not actually using com.android.support:appcompat-v7 in one place, but instead are adding appcompat-v7 by some other means (e.g., directly compiling against a copy of that library project).
What can't happen is your double-the-size scenario, as you cannot have two copies of the same Java class in a single APK.

Cannot use ParseLoginUI along with the Parse SDK

In my project I'm using the Parse SDK and now i want to add the ParseLoginUI library from here:
https://github.com/ParsePlatform/ParseUI-Android
I imported the library into my eclipse but i cannot use it inside my project.
Every time i try to include it as a library to my project, it gives me this error
Jar mismatch! Fix your dependencies
Any help

The problem is that the parse.jar file in the Parse SDK and in the login library are different versions. You can replace one with the other, and everything should work fine (found in the 'lib' folder). If you're using gradle to build the project, you'll need to appropriately adjust the dependencies config.
I will note that the Login UI library comes with no associated JavaDocs (and it's behind the SDK .jar by one version), so if you don't want to lose the convenient access to the docs, you should replace the .jar file in the login library with the one from the SDK, and not vice versa.
Alternatively, you can remove the parse.jar completely from you main project, and it will draw it from the loginUI library.

Jar mismatch scenario

I'm encountering a lot of jar mismatch errors lately and I'd like to avoid them in the future.
So, here's my question: suppose I have an app that uses 2 library projects, both of which use the v4 support library jar. In total, I have 3 jar files. What can I do to avoid the jar mismatch error?
All I've read so far is the case where you have a project and a single library project. In this case, I think your supposed to delete the jar file in the project and keep the one in the library project.

This is quite common if your project references several libraries, and each library references the same other library.
An example of this, your app is referencing the android support library v4, and you have 2 libraries which are also referencing the support library v4.
If you update your apps reference to the support library, but you don't update the support library v4 in your other libraries you will see this error.
The best thing is on each referenced library and your app, right click on the project > android tools > add support library. This will get the latest version and you should no longer see these errors.

If you're facing mismatch issue then simply copy one of them and paste in remaining libraries. E.g. as you've 3 v4 support library jars then copy one of them and paste at place of remaining two jars.

Try to understood by my example I used Map and Facebook in My project now Facebook,Map and my project have Android support jar so i removed Android Support jar from Facebook,My project but remain jar on Map,now i'm addded Android-Map-Extension as library project on Facebook And finally add Facebook library project on My project .....

Building Android project with ant having a library project dependency on another library project

I have maybe this not so common setup:
(> = dependency)
Android project > Android library project 1 > Android library project 2
So I have an Android library project which has a dependency to another library project.
When I'm building project in Eclipse everythings works fine but I cannot get my build working with Ant.
First Ant compiles Android library project 2 which generates a classes.jar and puts this file in the bin folder.
Then Ant tries to compile the Android library project 1 but then I'm getting errors becouse it is missing classes from Android library project 2.
Well this is not so weird becouse the jar file is not included in the libs folders.
But in project.properties i've made a dependency to the library project 2 so why does Ant not copy the classes.jar to the libs folders of library project 1?
Well I can think of a solution to use an Ant task to copy the file to the libs folder, but then I have to modify the build.xml which I do not prefer.
** EDIT
The problem is that the R class is missing, when I look in classes.jar this java file does not contain the R class. So my solution would proberly not work.

This behaviour was caused by a change in R17 of the build tools: http://tools.android.com/recent/dealingwithdependenciesinandroidprojects
In a nutshell: R files for libraries are no longer packaged in the classes.jar for that library. However, since the pareent.R for the parent-library (project1 in your example) also contains the resource-references for the 'child' library (project2 in your example), you don't have to refer to the child-R anyway.
Replace all project2.R-import statements in project1 with project1.R import statements and you should be fine.

For ant to compile add dependency in ant.properties.
eg:
android.library.reference.1=../path/to/library

This sounds like a very brittle setup - you may have good reason for this, but could you instead decouple the libraries dependence on each other?
For example; implement a bridge pattern to translate the calls between both libraries, and make the calling Android project attach them. This way, you have no code in either library that depends on the other, and the only project that needs to handle dependency setup is your main project.
One of the main reasons for using a library is to make the code re-usable, this approach ensures someone (you, a colleague, your successor...) could plug in just one library and create their own implementation of the other one.
Here is another good article on applying the bridge pattern in Java: http://java.dzone.com/articles/design-patterns-bridge

Well the problem was that the R class was missing.
So i removed the R class dependency between the two library projects.
I don't know if this is fixable but i think it is bad practice any way.
Without this dependency Ant builds fine.

Old question, but like me, others might be banging their head on this...
The official answer is "it cannot be done", specifically:
At build time, the libraries are merged with the application one at a time, starting from the lowest priority to the highest. Note that a library cannot itself reference another library and that, at build time, libraries are not merged with each other before being merged with the application.
(extracted from the official documentation: "Referencing a Library Project").
Which means that anything goes, as there is no "clean" way to do it with the tools (and dirty methods are in order).
Hope it helps

Expose an "Android Library Project"'s included jars to Projects which reference them

One of the newer functions of Android is the ability to create a Library Project.
This is great for unit testing and sharing common functionality across many apps you may be developing, but I seem to have stumbled upon a bug in their implementation.
When you have the following situation:
-LibraryProject contains LibraryProject/libs/folder/lib.jar in it's build path.
-ReferencingProject references LibraryProject.
From ReferencingProject you don't have access to anything inside lib.jar (Such as constant's used to communicate with methods in the Library Project).
A solution to this is to include "lib.jar" as an external library in the referencing project but this approach begins to negate the benefits you gain from having a self contained Library Project by creating multiple manually added references to resources which could move/change during the development of the library project (not to mention cause some pretty confusing errors).
Is there any way to expose an included libs classes to the referencing project without having to manually reference them as external jars?

As #Selvin says,
In the Library Project you can specify which libraries you want to mark as "exported" in the window brought up by using: Project properties => Java Build Path => Order and Export. From this example you would check libs/folder/lib.jar.
Clean and build the Library Project and the "exported" libraries are now included in the produced jar.
EDIT
This is a symptom of upgrading to ADT 17 - (Android Team: Perhaps put a few warnings on your release notes when an update breaks existing architectures?)
http://tools.android.com/recent/dealingwithdependenciesinandroidprojects
If you don't want to add the library to the "Order and Export" then placing local jar's in /libs/ base folder will automatically add it to "Android Dependencies" which are exported in the jar created from your shared library.
EDIT2
Recent ADT upgrade would have you also manually select "Android Dependencies" as "Exported" in your Java Build Path. Again, warning would be nice.