The import android.support cannot be resolved

I am trying to run the code provided HERE
I downloaded the code from their Github and imported into Android SDK, but it shows error at the lines

import android.support.v4.app.FragmentActivity;
import android.support.v4.app.NavUtils;

in multiple files. However if I check the Android SDK Manager, the Android Support Library as well as the Android Support Repository in the Extras folder are both installed. I can also see the support folder and it's contents in the SDK_INSTALL\sdk\extras\android\support directory. It also has the v4 folder which also contains the android-support-v4.jar and the src folder. THen why is it still showing the error, how do I resolve it and how do I get that sample code running? THe sample code is for an RSS reader app, if that's relevant.

Solution

Follow these steps:

For Eclipse:

Go to your Project's Properties
Navigate to the Java Build Path
Then go to the Libraries tab. There click the Add External JARs Button on the Right pane.
Select the android-support-v4.jar file, usually the path for the Jar file is :
YOUR_DRIVE\android-sdks\extras\android\support\v4\android-support-v4.jar
After adding android-support-v4.jar Library, navigate to the Order and Export tab and put check mark on the android-support-v4 Library file.
After doing the above, Clean the Project and Build it.
Problem Solved.

For Android Studio:

Short Version:

Add the following line to your build.gradle file:
implementation 'com.android.support:support-v4:YOUR_TARGET_VERSION'

Long Version:

Go to File -> Project Structure
Go to "Dependencies" Tab -> Click on the Plus sign -> Go to "Library dependency"
Select the support library "support-v4 (com.android.support:support-v4:YOUR_TARGET_VERSION)"
Navigate to your "build.gradle" inside your App Directory and double check if your desired Android Support Library has been added to your dependencies.
Rebuild your project and now everything should work.

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