如何在ViewPager上进行循环滚动？

我想将我的ViewPager设置为循环滚动.我希望第一页能够滚动到第2页和最后一页.我希望我的最后一页滚动到[最后一页-1]和第一页.我已经尝试了,虽然我不确定何时调用我创建的方法.在ViewPager中似乎没有一种方法可以处理这种事情,所以我创建了以下内容.

    public ViewPagerAdapter(final ViewPager pager, int... pageIDs) {
        super();
        int actualNoOfIDs = pageIDs.length;
        count = actualNoOfIDs + 2;
        Log.d(TAG, "actualNoOfIDs: " + actualNoOfIDs +
                "count: " + count);

        pageIDsArray = new int[count];
        for (int i = 0; i < actualNoOfIDs; i++) {
            pageIDsArray[ i + 1] = pageIDs[i];
        }
        pageIDsArray[0] = pageIDs[actualNoOfIDs - 1];
        pageIDsArray[count - 1] = pageIDs[0];

        Log.d(TAG, "actualNoOfIDs#2: " + actualNoOfIDs +
                "count#2: " + count);
        pager.setOnPageChangeListener(new OnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                int pageCount = getCount();
                if (position == 0) {
                    pager.setCurrentItem(pageCount - 2, false);
                } else if (position == pageCount - 1) {
                    pager.setCurrentItem(1, false);
                }
            }

            @Override
            public void onPageScrollStateChanged(int state) {
                // TODO Auto-generated method stub
                Log.d(TAG, "onPageScrollStateChanged()");
//              if (state == ViewPager.SCROLL_STATE_IDLE) { 
//                  int pageCount = getCount(); 
//                  int currentItem = pager.getCurrentItem(); 
//                  if (currentItem == 0) { 
//                      pager.setCurrentItem(pageCount - 2, false); 
//                  } else if (currentItem == pageCount - 1) { 
//                      pager.setCurrentItem(1, false); 
//                  } 
//              } 

            }

            @Override
            public void onPageScrolled(int position, float positionOffset, 
                    int positionOffsetPixels) {
                // TODO Auto-generated method stub
                Log.d(TAG, "onPageScrolled()");

            }
        });
    }

我的整个代码有点冗长,但如果有帮助我可以发布它.

public class ViewPagerAdapter extends PagerAdapter {
    public static String TAG = ViewPagerAdapter.class.getSimpleName();

    private int count;
    private int[] pageIDsArray;

    private TextToSpeech btnTTS;
    private TtsButton tTSBtn;

    String inputTxt;
    Context context;
    View itemView;

    TextView tvNumber; // container for atomic number
    TextView tvSymbol; // container for symbol
    TextView tvWeight; // container for weight
    TextView tvName; // container for name
    TextView tvGroup; // container for group
    TextView tvPeriod; // container for period
    TextView tvBlock; // container for block
    TextView tvFamily; // container for family
    TextView tvColor; // container for color
    TextView tvPhase; // container for phase
    TextView tvMelt; // container for melting point
    TextView tvBoil; // container for boiling point
    TextView tvNeutrons; // container for neutrons
    TextView tvProtons; // container for protons
    TextView tvElectrons; // container for electrons
    TextView tvUrl; // container for electrons

    public ViewPagerAdapter(Context context, List arrayAtomicNum, 
            List arrayName, List arraySymbol, List arrayFamily,
            List arrayPhase, List arrayColor, List arrayGroup, 
            List arrayPeriod, List arrayBlock, List arrayProtons,
            List arrayNeutrons, List arrayElectrons, List arrayWeight,
            List arrayMelt, List arrayBoil, List arrayUrl) {    
        this.context = context;
        ElementStructure.arrayAtomicNum = arrayAtomicNum;
        ElementStructure.arrayName = arrayName;
        ElementStructure.arraySymbol = arraySymbol;
        ElementStructure.arrayFamily = arrayFamily;
        ElementStructure.arrayPhase = arrayPhase;
        ElementStructure.arrayColor = arrayColor;
        ElementStructure.arrayGroup = arrayGroup;
        ElementStructure.arrayPeriod = arrayPeriod;
        ElementStructure.arrayBlock = arrayBlock;
        ElementStructure.arrayProtons = arrayProtons;
        ElementStructure.arrayNeutrons = arrayNeutrons;
        ElementStructure.arrayElectrons = arrayElectrons;
        ElementStructure.arrayWeight = arrayWeight;
        ElementStructure.arrayMelt = arrayMelt;
        ElementStructure.arrayBoil = arrayBoil;
        ElementStructure.arrayUrl = arrayUrl;
    }


    public ViewPagerAdapter(final ViewPager pager, int... pageIDs) {
        super();
        int actualNoOfIDs = pageIDs.length;
        count = actualNoOfIDs + 2;
        Log.d(TAG, "actualNoOfIDs: " + actualNoOfIDs +
                "count: " + count);

        pageIDsArray = new int[count];
        for (int i = 0; i < actualNoOfIDs; i++) {
            pageIDsArray[ i + 1] = pageIDs[i];
        }
        pageIDsArray[0] = pageIDs[actualNoOfIDs - 1];
        pageIDsArray[count - 1] = pageIDs[0];

        Log.d(TAG, "actualNoOfIDs#2: " + actualNoOfIDs +
                "count#2: " + count);
        pager.setOnPageChangeListener(new OnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                int pageCount = getCount();
                if (position == 0) {
                    pager.setCurrentItem(pageCount - 2, false);
                } else if (position == pageCount - 1) {
                    pager.setCurrentItem(1, false);
                }
            }

            @Override
            public void onPageScrollStateChanged(int state) {
                // TODO Auto-generated method stub
                Log.d(TAG, "onPageScrollStateChanged()");
//              if (state == ViewPager.SCROLL_STATE_IDLE) { 
//                  int pageCount = getCount(); 
//                  int currentItem = pager.getCurrentItem(); 
//                  if (currentItem == 0) { 
//                      pager.setCurrentItem(pageCount - 2, false); 
//                  } else if (currentItem == pageCount - 1) { 
//                      pager.setCurrentItem(1, false); 
//                  } 
//              } 

            }

            @Override
            public void onPageScrolled(int position, float positionOffset, 
                    int positionOffsetPixels) {
                // TODO Auto-generated method stub
                Log.d(TAG, "onPageScrolled()");

            }
        });
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return ElementStructure.arrayAtomicNum.size();

    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        // TODO Auto-generated method stub
        return view == ((RelativeLayout) object);
    }

    @Override
    public Object instantiateItem(ViewGroup container, final int position) {

        LayoutInflater inflater = (LayoutInflater) context
             .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        int layoutColorId = ElementStructure.arrayLayoutColor.get(position);

        if (layoutColorId == 1) {
            itemView = inflater.inflate(R.layout.frame_learn_a, container,
                     false);
        } else if (layoutColorId == 2) {
            itemView = inflater.inflate(R.layout.frame_learn_b, container,
                     false);
        } else if (layoutColorId == 3) {
            itemView = inflater.inflate(R.layout.frame_learn_c, container,
                     false);
        } else if (layoutColorId == 4) {
            itemView = inflater.inflate(R.layout.frame_learn_d, container,
                     false);    
        }

        Button btnSpeak = (Button)itemView.findViewById(R.id.btnaudio);

        btnSpeak.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                inputTxt = ElementStructure.arrayName.get(position);
                tTSBtn = new TtsButton(this, inputTxt); 
            }

        });

        // atomic number textView
        tvNumber = (TextView)itemView.findViewById(R.id.metanumber);

        // symbol textView
        tvSymbol = (TextView)itemView.findViewById(R.id.metasymbol);

        // weight textView
        tvWeight = (TextView)itemView.findViewById(R.id.metaweight);

        // name textView
        tvName = (TextView)itemView.findViewById(R.id.metaname);

        // group textView
        tvGroup = (TextView)itemView.findViewById(R.id.metagroup);

        // period textView
        tvPeriod = (TextView)itemView.findViewById(R.id.metaperiod);

        // block textView
        tvBlock = (TextView)itemView.findViewById(R.id.metablock);

        // family textView
        tvFamily = (TextView)itemView.findViewById(R.id.metafamily);

        // color textView
        tvColor = (TextView)itemView.findViewById(R.id.metacolor);

        // phase textView
        tvPhase = (TextView)itemView.findViewById(R.id.metaphase);

        // melting point textView
        tvMelt = (TextView)itemView.findViewById(R.id.metamelt);

        // boiling point textView
        tvBoil = (TextView)itemView.findViewById(R.id.metaboil);

        // neutrons textView
        tvNeutrons = (TextView)itemView.findViewById(R.id.metaneutrons);

        // protons textView
        tvProtons = (TextView)itemView.findViewById(R.id.metaprotons);

        // electrons textView
        tvElectrons = (TextView)itemView.findViewById(R.id.metaelectrons);

        // url textView
        tvUrl = (TextView)itemView.findViewById(R.id.metaurl);

        // capture position and set to the TextViews
        tvNumber.setText(String.valueOf(ElementStructure.arrayAtomicNum.get(position)));
        tvSymbol.setText(ElementStructure.arraySymbol.get(position));
        tvWeight.setText(String.valueOf(ElementStructure.arrayWeight.get(position)));
        tvName.setText(ElementStructure.arrayName.get(position));
        tvPeriod.setText(String.valueOf(ElementStructure.arrayPeriod.get(position)));
        tvBlock.setText(String.valueOf(ElementStructure.arrayBlock.get(position)));
        tvFamily.setText(ElementStructure.arrayFamily.get(position));
        tvColor.setText(ElementStructure.arrayColor.get(position));
        tvPhase.setText(ElementStructure.arrayPhase.get(position));
        tvNeutrons.setText(String.valueOf(ElementStructure.arrayNeutrons.get(position)));
        tvProtons.setText(String.valueOf(ElementStructure.arrayProtons.get(position)));
        tvElectrons.setText(String.valueOf(ElementStructure.arrayElectrons.get(position)));
        tvUrl.setText(ElementStructure.arrayUrl.get(position));

        // capture position, adjust for 0 value cases
        if (ElementStructure.arrayGroup.get(position) == 0) {
            tvGroup.setText("n/a");
        } else {
            tvGroup.setText(String.valueOf(ElementStructure.arrayGroup.get(position)));
        }

        if (ElementStructure.arrayMelt.get(position) == 0) {
            tvMelt.setText("n/a");
        } else {
            tvMelt.setText(String.valueOf(ElementStructure.arrayMelt.get(position)));
        }

        if (ElementStructure.arrayBoil.get(position) == 0) {
            tvBoil.setText("n/a");
        } else {
            tvBoil.setText(String.valueOf(ElementStructure.arrayBoil.get(position)));
        }

        // add fragments to container (ViewPager)
        ((ViewPager) container).addView(itemView);
        return itemView;

    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        Log.d(TAG, "destroyItem()");
        // remove fragments from container (ViewPager)
        ((ViewPager) container).removeView((RelativeLayout) object);
    }


    @Override
    public void finishUpdate(View container) {
        // TODO Auto-generated method stub
        Log.d(TAG, "finishUpdate()");
    }

    @Override
    public void restoreState(Parcelable state, ClassLoader loader) {
        // TODO Auto-generated method stub
        Log.d(TAG, "restoreState()");
    }

    @Override
    public Parcelable saveState() {
        // TODO Auto-generated method stub
        Log.d(TAG, "saveState()");
        return null;
    }

    @Override
    public void startUpdate(View container) {
        // TODO Auto-generated method stub
        Log.d(TAG, "startUpdate()");
    }




    public class TtsButton extends Activity implements OnInitListener {

        public TtsButton(OnClickListener onClickListener, String inputTxt) {
            super();
            tTSCheck(inputTxt);
        }

        private void tTSCheck (String inputTxt) {

            int resultCodeCheck = TextToSpeech.Engine.CHECK_VOICE_DATA_PASS;
            if (resultCodeCheck == 1) {
                btnTTS = new TextToSpeech(context, this);
            } else {
                Intent installTTSFiles = new Intent(); //missing data, install it
                installTTSFiles.setAction(TextToSpeech.Engine.ACTION_INSTALL_TTS_DATA);
                startActivity(installTTSFiles);
            }
        }

        @Override
        public void onInit(int status) {
            // TODO Auto-generated method stub
            if(status == TextToSpeech.SUCCESS)
            {
                Log.i(TAG, "TTS INIT: SUCCESS");
                btnTTS.setLanguage(Locale.US);
                btnTTS.speak(inputTxt, TextToSpeech.QUEUE_FLUSH, null);
            }
            else if(status == TextToSpeech.ERROR)
            {
                Log.e(TAG, "TTS INIT: ERROR");
            }
        }

        @Override
        public void onPause() {
            if (btnTTS != null) {
                btnTTS.stop();
                btnTTS.shutdown();
            }
            super.onPause();
        }

    } //end embedded class

} //end ViewPagerAdapter

提前致谢.我正在考虑尝试使用动作手势,但是,我真的不明白为什么我的方法不能工作这么久以至于我可以在正确的位置调用它.我最初的想法是每次位置改变时调用它在"Object instantiateItem(ViewGroup容器,最终的int位置)",如果条件是正确的.但我不确定这是不是最好的.