Question

I know there are some topics about this here already but I could not find a solution which I could get to work for my case.

I have a working sliding gallery using a custom FragmentActivity and FragmentPagerAdapter which holds a list of Fragments.

Within the FragmentActivity is a ImageView “delete”. If clicked, the function deleteMedia() is called which then should remove the current Fragment and the following Fragment should be displayed.
How would I have to do that in my example?

FragmentActivity:

public class GalleryPagerActivity extends FragmentActivity implements OnClickListener {

    private Intent intent;
    private SharedPreferences settings;
    private PagerAdapter mPagerAdapter;
    private ViewPager mPager;
    private List<Fragment> fragments;
    private List<WhiteboardMedia> wiList;

    private int selectedPosition;
    private LinearLayout llTop;
    private TextView tvTop;
    private ImageView delete;
    private ImageView share;
    private TextView tvCounter;
    private TextView tvFilename;
    private TextView tvFilesize;
    private TextView tvDate;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        try {
            super.setContentView(R.layout.gallery_pager);

            intent = getIntent();

            Type collectionType = new TypeToken<List<WhiteboardMedia>>(){}.getType();

            wiList = gson.fromJson(intent.getStringExtra("wiList"), collectionType);
            selectedPosition = intent.getIntExtra("position", 1);

            llTop = (LinearLayout) findViewById(R.id.llTop);
            llTop.setOnClickListener(this);
            tvTop = (TextView) findViewById(R.id.tvTop);
            tvTop.setOnClickListener(this);
            delete = (ImageView) findViewById(R.id.imgDelete);
            delete.setOnClickListener(this);
            share = (ImageView) findViewById(R.id.imgShare);
            share.setOnClickListener(this);

            tvCounter = (TextView) findViewById(R.id.tvCounter);
            tvFilename = (TextView) findViewById(R.id.tvFilename);
            tvFilesize = (TextView) findViewById(R.id.tvFilesize);
            tvDate = (TextView) findViewById(R.id.tvDate);

            createContextMenu();
            initDropbox();
        } catch (Exception e) {
            Log.e("GalleryPagerActivity", e.getLocalizedMessage());
        }
    }

    /**
     * Initialise the pager
     */
    private void initialisePager() {
        mPager = (ViewPager) super.findViewById(R.id.viewpager);
        mPager.setAdapter(this.mPagerAdapter);
        mPager.setOnPageChangeListener(new GalleryPageListener(tvCounter, tvFilename, tvFilesize, tvDate, wiList));

        mPager.setCurrentItem(selectedPosition, true);
        updatePage(selectedPosition);
    }

    public void updatePage(int position)
    {
        int focusedPage = position + 1;
        Log.i("onPageSelected", "page selected " + position);

        WhiteboardMedia wiImage = wiList.get(position);

        String imageDate = "N/A";
        try {
            Date dateTaken= new Date(); //wiImage.getDate();
            SimpleDateFormat sdf = new SimpleDateFormat("yy/MM/dd");
            imageDate = sdf.format(dateTaken);
        } catch (Exception e) {
        }

        try {
            tvCounter.setText(focusedPage + "/" + wiList.size());
            tvFilename.setText(wiImage.getFilename());
            tvFilesize.setText(wiImage.getSize() + "a");
            tvDate.setText(imageDate);
        } catch (Exception e) {
        }
    }

    @Override
    protected void onResume() {
        super.onResume();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
    }

    private WhiteboardMedia getActiveWhiteboardImage() {
        return wiList.get(mPager.getCurrentItem());
    }

    private final int DELETE = 1;

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        menu.add(1, DELETE, 2, R.string.delete).setIcon(R.drawable.menu_btn_trash);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case DELETE:
            deleteMedia();
            return true;
        }
        return super.onContextItemSelected(item);
    }

    @Override
    public void onClick(View v) {
        if (v == delete) {
            deleteMedia();
        }
    }

    private void deleteMedia() {
        // TODO delete the active Fragment and display the next Fragment in the list
    }

    /******************************************************************************
     * Context Menu
     *****************************************************************************/
    private void createContextMenu() {
        // context menu stuff
    }

    @Override
    protected Dialog onCreateDialog(int id) {
        // stuff
    }

}

FragmentPagerAdapter:

public class GalleryPagerAdapter extends FragmentPagerAdapter {

private final List<Fragment> fragments;

public GalleryPagerAdapter(FragmentManager fm, List<Fragment> fragments) {
    super(fm);
    this.fragments = fragments;
}

@Override
public Fragment getItem(int position) {
    return this.fragments.get(position);
}

@Override
public int getCount() {
    return this.fragments.size();
}
}

Thanks for help!

Answer 1

First, I suggest that you consider altering your FragmentPagerAdapter, to look more like the sample. You normally do not hold a list of fragments, any more than an ArrayAdapter normally holds a list of Views for the rows. Normally, you create the fragments on demand, and somebody else holds the list.

Then, to delete something, delete it from your model data (what the FragmentPagerAdapter normally wraps). Make sure that getCount() will then return the right number of items. Then, call notifyDataSetChanged() on the FragmentPagerAdapter, which should trigger a redraw of the ViewPager.