PagerActivity.java

## main.xml
<!-- Copyright (c) 2012 Wireless Designs, LLC

 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
 "Software"), to deal in the Software without restriction, including
 without limitation the rights to use, copy, modify, merge, publish,
 distribute, sublicense, and/or sell copies of the Software, and to
 permit persons to whom the Software is furnished to do so, subject to
 the following conditions:

 The above copyright notice and this permission notice shall be
 included in all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-->

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.example.pagercontainer.PagerContainer
        android:id="@+id/pager_container"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#CCC">
        <android.support.v4.view.ViewPager
            android:layout_width="150dp"
            android:layout_height="100dp"
            android:layout_gravity="center_horizontal" />
    </com.example.pagercontainer.PagerContainer>

</RelativeLayout>

## PagerActivity.java
/*
 * Copyright (c) 2012 Wireless Designs, LLC
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package com.example.pagercontainer;

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

/**
 * PagerActivity: A Sample Activity for PagerContainer
 */
public class PagerActivity extends Activity {

    PagerContainer mContainer;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        mContainer = (PagerContainer) findViewById(R.id.pager_container);

        ViewPager pager = mContainer.getViewPager();
        PagerAdapter adapter = new MyPagerAdapter();
        pager.setAdapter(adapter);
        //Necessary or the pager will only have one extra page to show
        // make this at least however many pages you can see
        pager.setOffscreenPageLimit(adapter.getCount());
        //A little space between pages
        pager.setPageMargin(15);

        //If hardware acceleration is enabled, you should also remove
        // clipping on the pager for its children.
        pager.setClipChildren(false);
    }

    //Nothing special about this adapter, just throwing up colored views for demo
    private class MyPagerAdapter extends PagerAdapter {

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            TextView view = new TextView(PagerActivity.this);
            view.setText("Item "+position);
            view.setGravity(Gravity.CENTER);
            view.setBackgroundColor(Color.argb(255, position * 50, position * 10, position * 50));

            container.addView(view);
            return view;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            container.removeView((View)object);
        }

        @Override
        public int getCount() {
            return 5;
        }

        @Override
        public boolean isViewFromObject(View view, Object object) {
            return (view == object);
        }
    }
}

## PagerContainer.java
/*
 * Copyright (c) 2012 Wireless Designs, LLC
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package com.example.pagercontainer;

import android.content.Context;
import android.graphics.Point;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.FrameLayout;

/**
 * PagerContainer: A layout that displays a ViewPager with its children that are outside
 * the typical pager bounds.
 */
public class PagerContainer extends FrameLayout implements ViewPager.OnPageChangeListener {

    private ViewPager mPager;
    boolean mNeedsRedraw = false;

    public PagerContainer(Context context) {
        super(context);
        init();
    }

    public PagerContainer(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public PagerContainer(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init();
    }

    private void init() {
        //Disable clipping of children so non-selected pages are visible
        setClipChildren(false);

        //Child clipping doesn't work with hardware acceleration in Android 3.x/4.x
        //You need to set this value here if using hardware acceleration in an
        // application targeted at these releases.
        setLayerType(View.LAYER_TYPE_SOFTWARE, null);
    }

    @Override
    protected void onFinishInflate() {
        try {
            mPager = (ViewPager) getChildAt(0);
            mPager.setOnPageChangeListener(this);
        } catch (Exception e) {
            throw new IllegalStateException("The root child of PagerContainer must be a ViewPager");
        }
    }

    public ViewPager getViewPager() {
        return mPager;
    }

    private Point mCenter = new Point();
    private Point mInitialTouch = new Point();

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        mCenter.x = w / 2;
        mCenter.y = h / 2;
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        //We capture any touches not already handled by the ViewPager
        // to implement scrolling from a touch outside the pager bounds.
        switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                mInitialTouch.x = (int)ev.getX();
                mInitialTouch.y = (int)ev.getY();
            default:
                ev.offsetLocation(mCenter.x - mInitialTouch.x, mCenter.y - mInitialTouch.y);
                break;
        }

        return mPager.dispatchTouchEvent(ev);
    }

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
        //Force the container to redraw on scrolling.
        //Without this the outer pages render initially and then stay static
        if (mNeedsRedraw) invalidate();
    }

    @Override
    public void onPageSelected(int position) { }

    @Override
    public void onPageScrollStateChanged(int state) {
        mNeedsRedraw = (state != ViewPager.SCROLL_STATE_IDLE);
    }
}