在 viewpager 中如何实现 Button 的 onClick 方法

我想在viewpaper中，点击按钮弹出Toast信息，并且想知道如何在viewpaper上访问views？
我用的以下的代码，不好用。

public class MyPagerAdapter extends PagerAdapter {

    @Override
    public int getCount() {
        return 3;
    }

    @Override
    public Object instantiateItem(final View collection, final int position) {
         v = new View(collection.getContext());
        LayoutInflater inflater =
                (LayoutInflater) collection.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        int resId = 0;
        switch (position) {
        case 0:
            resId = R.layout.cate1;
            v = inflater.inflate(R.layout.cate1, null, false);
            add1 = (Button) v.findViewById(R.id.btnAdd);
            add1.setOnClickListener( new OnClickListener() {
                public void onClick(View m) {
                   Toast.makeText(collection.getContext(),"click",Toast.LENGTH_LONG).show();
                }
            });


            break;
        case 1:
            resId = R.layout.cate2;
            break;
        case 2:
            resId = R.layout.cate3;
            break;
        }

        View view = inflater.inflate(resId, null);
        ((ViewPager) collection).addView(view, 0);

        return view;
    }

    @Override
    public void destroyItem(final View arg0, final int arg1, final Object arg2) {
        ((ViewPager) arg0).removeView((View) arg2);

    }

    @Override
    public boolean isViewFromObject(final View arg0, final Object arg1) {
        return arg0 == ((View) arg1);

    }

    @Override
    public void finishUpdate(View arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void restoreState(Parcelable arg0, ClassLoader arg1) {
        // TODO Auto-generated method stub

    }

    @Override
    public Parcelable saveState() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public void startUpdate(View arg0) {
        // TODO Auto-generated method stub

    }
        }

下面是 button onclick代码，也没有实现

v = inflater.inflate(R.layout.cate1, null, false);
            add1 = (Button) v.findViewById(R.id.btnAdd);
            add1.setOnClickListener( new OnClickListener() {
                public void onClick(View m) {
                   Toast.makeText(collection.getContext(),"click",Toast.LENGTH_LONG).show();
                }
            });

请求大家的帮忙，看看如何处理这个问题。