The import android.support.v13.app.FragmentActivity cannot be resolved

Question 1

Change the "import android.support.v13.app.FragmentActivity" to "import android.support.v4.app.FragmentActivity"

For the undefined part, try this syntax:

public class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter {
    public ScreenSlidePagerAdapter (android.support.v4.app.FragmentManager fm) {
        super(fm);
    }

and:

@Override
    public android.support.v4.app.Fragment getItem(int position) {
        return ScreenSlidePagerAdapter.create(position);
    }

Original suggestion: Have you added the libraries to your build path? Just right-click on the project and the menu item "Java Build Path" will be listed. Select this and add the libraries to your path.

Question 2

I was blocked on this for a while and just managed to fix it,

Try using getSupportFragmentManager() instead of getFragmentManager().

Question 3

Here is a full code for further reference

package com.team.test;

import android.content.Intent;
import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.app.NavUtils;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.Menu;
import android.view.MenuItem;

/**
 * Demonstrates a "screen-slide" animation using a {@link ViewPager}. Because
 * {@link ViewPager} automatically plays such an animation when calling
 * {@link ViewPager#setCurrentItem(int)}, there isn't any animation-specific
 * code in this sample.
 * 
 * <p>
 * This sample shows a "next" button that advances the user to the next step in
 * a wizard, animating the current screen out (to the left) and the next screen
 * in (from the right). The reverse animation is played when the user presses
 * the "previous" button.
 * </p>
 * 
 * @see ScreenSlidePageFragment
 */
public class MenuActivity extends FragmentActivity {
    /**
     * The number of pages (wizard steps) to show in this demo.
     */
    private static final int NUM_PAGES = 6;

    /**
     * The pager widget, which handles animation and allows swiping horizontally
     * to access previous and next wizard steps.
     */
    private ViewPager mPager;

    /**
     * The pager adapter, which provides the pages to the view pager widget.
     */
    private PagerAdapter mPagerAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        setContentView(R.layout.activity_screen_slide);

        // Instantiate a ViewPager and a PagerAdapter.
        mPager = (ViewPager) findViewById(R.id.pager);
        mPagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager());
        mPager.setAdapter(mPagerAdapter);
        mPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                // When changing pages, reset the action bar actions since they
                // are dependent
                // on which page is currently active. An alternative approach is
                // to have each
                // fragment expose actions itself (rather than the activity
                // exposing actions),
                // but for simplicity, the activity provides the actions in this
                // sample.
                invalidateOptionsMenu();
            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);
        getMenuInflater().inflate(R.menu.activity_screen_slide, menu);

        menu.findItem(R.id.action_previous).setEnabled(
                mPager.getCurrentItem() > 0);

        // Add either a "next" or "finish" button to the action bar, depending
        // on which page
        // is currently selected.
        MenuItem item = menu
                .add(Menu.NONE,
                        R.id.action_next,
                        Menu.NONE,
                        (mPager.getCurrentItem() == mPagerAdapter.getCount() - 1) ? R.string.action_finish
                                : R.string.action_next);
        item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
                | MenuItem.SHOW_AS_ACTION_WITH_TEXT);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case android.R.id.home:
            // Navigate "up" the demo structure to the launchpad activity.
            // See http://developer.android.com/design/patterns/navigation.html
            // for more.
            NavUtils.navigateUpTo(this, new Intent(this, Login.class));
            return true;

        case R.id.action_previous:
            // Go to the previous step in the wizard. If there is no previous
            // step,
            // setCurrentItem will do nothing.
            mPager.setCurrentItem(mPager.getCurrentItem() - 1);
            return true;

        case R.id.action_next:
            // Advance to the next step in the wizard. If there is no next step,
            // setCurrentItem
            // will do nothing.
            mPager.setCurrentItem(mPager.getCurrentItem() + 1);
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    /**
     * A simple pager adapter that represents 5 {@link ScreenSlidePageFragment}
     * objects, in sequence.
     */
    public class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter {
        public ScreenSlidePagerAdapter(android.support.v4.app.FragmentManager fm) {
            super(fm);
        }

        @Override
        public android.support.v4.app.Fragment getItem(int position) {
            return ScreenSlidePageFragment.create(position);
        }

        @Override
        public int getCount() {
            return NUM_PAGES;
        }
    }
}

Question 4

I think i should explain the difference...

if you want to support api <11. Then you should import android.support.v4.app.FragmentPagerAdapter; and then create all Fragment by import android.support.v4.app.Fragment; and you are done.

API==11

If you don't want to support api <11. or you simply want to use simple Fragment(without support) then you should import android.support.v13.app.FragmentPagerAdapter; then getItem will need a simple Fragment.

@Override
    public android.app.Fragment getItem(int position) {
        return ScreenSlidePagerAdapter.create(position);
    }