Question

I have a ViewPager that has one ImageView per view. I need to setup an OnTouchListener for the currentItem in the view. I have the following code but keep getting NULL when I try and setup the listener. Below is my code. How can I get a valid reference to my current items ImageView???

private class CalendarPagerAdapter extends PagerAdapter {

        public int getCount() {
            return NUM_VIEW;
        }

        public Object instantiateItem(View collection, int position) {

            View view=null;

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

            int resId = 0;
            switch (position) {
            case 0:
                resId = R.layout.cal_july;
                view = inflater.inflate(resId, null);
                calendar = (ImageView) findViewById(R.id.imageView1);
                                // IT IS ALWAYS NULL HERE
                if(calendar == null) {
                    System.out.println("its null!!!!!!");
                } else {
                    System.out.println("its NOT NULL!!!!!");
                }
                // Breaks here, obviously!!!
                calendar.setOnTouchListener(getOnTouchListener());
                break;
            case 1:
                resId = R.layout.cal_august;
                view = inflater.inflate(resId, null);
                calendar = (ImageView) findViewById(R.id.imageView1);
                calendar.setOnTouchListener(getOnTouchListener());
                break;              
            case 2:
                resId = R.layout.cal_september;
                break;
            case 3:
                resId = R.layout.cal_october;
                break;
            case 4:
                resId = R.layout.cal_november;
                break;

            }

            ((ViewPager) collection).addView(view, 0);

            return view;
        }

Answer 1

When you call:

view = inflater.inflate(resId, null);
calendar = (ImageView) findViewById(R.id.imageView1);

it looks for the ImageView with the ID R.id.imageView1 in your Activity’s contentView (ie: the layout that you originally set in your onCreate(). I assume that isn’t what you want.

You probably want to find the view in the view you just inflated. Try this:

view = inflater.inflate(resId, null);
calendar = (ImageView) view.findViewById(R.id.imageView1);