Passing a Fragment in the constructor of an Adapte

问题:

Since the onClick event is never triggered on a ViewPager (see this question), I'm going to set the onClickListener to the item container in the adapter.

The idea is, when an item is clicked, to call from the adapter a method from the Fragment in which this adapter is set to the ViewPager.

For an Activity I would pass the context and call the method using this context (something like ((myActivity)context).itemContainerOnClick()).

But how can I do with a Fragment? Could I face any issue passing the Fragment as an argument to my adapter's constructor?

Thanks

Fragment

public class MyFragment extends Fragment {

    ViewPager mViewPager;

    int mPosition = 0;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        view = (RelativeLayout) inflater.inflate(R.layout.my_fragment_container, container, false);

        ViewPager viewPager = (ViewPager) view.findViewById(R.id.viewpager);

        mViewPager.setAdapter(new MyAdapter(getActivity(), myObjectArray);

        mViewPager.setOnPageChangeListener(new OnPageChangeListener() {

            @Override
            public void onPageSelected(int position) {
                mPosition = position;
            }

            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {}

            @Override
            public void onPageScrollStateChanged(int state) {}
        });

        mViewPager.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // I want to start some activity, passing mPosition
                // but this is never called
            }
        }); 


        return view;
    }

    // Alternative to mViewPager.setOnClickListener, called from the adapter
    public void onViewPagerClick()
    {
        // start some activity, passing mPosition
    } 
}

PageAdapter

class MyAdapter extends PagerAdapter {

    private MyObject[] mItemArray;
    private Context mContext;

    public SejoursWidgetAdapter(Context context, MyObject[] itemArray) {
        mContext = context;
        mItemArray = itemArray;
    }

    @Override
    public Object instantiateItem(View collection, int position) {

        LayoutInflater inflater = (LayoutInflater) collection.getContext()
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        View row = inflater.inflate(R.layout.item, null);      

        // Add click listener here because setting it directly on the ViewPager does not work (onClick not triggered)       
        row.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // How can I call MyFragment's onViewPagerClick() ?
            }
        }); 

        ((ViewPager) collection).addView(row);        


        return row;
    }

    /* More stuff */

}

回答1:

Check my below code with Change of ItemClick.

 class MyAdapter extends PagerAdapter {

   private MyObject[] mItemArray;
   private Context mContext;

public SejoursWidgetAdapter(Context context, MyObject[] itemArray) {
    mContext = context;
    mItemArray = itemArray;
}

@Override
public Object instantiateItem(View collection, int position) {

    LayoutInflater inflater = (LayoutInflater) collection.getContext()
    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    View row = inflater.inflate(R.layout.item, null);      
     row .setTag(position);
    // Add click listener here because setting it directly on the ViewPager does not work (onClick not triggered)       
    row.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            // How can I call MyFragment's onViewPagerClick() ?

          int position=(Integer) v.getTag();
     Log.v("Log_tag", "Here image is clicked"+ position);
        //now you known which Page is click you can do what you want.
        }
    }); 

    ((ViewPager) collection).addView(row);        


    return row;
}

/* More stuff */

 }

回答2:

you can also get the position of current page from your mViewPager by

int position = mViewPager.getCurrentItem();

instead of

int position=(Integer) v.getTag();