Multiple selection in custom ListView with CAB

See if the code helps you(it’s basically a ListActivity with a custom adapter to hold the status of checked items(+ different background)):

public class CABSelection extends ListActivity {

    private ArrayList<String> mItems = new ArrayList<String>();
    private SelectionAdapter mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        for (int i = 0; i < 24; i++) {
            mItems.add("Name" + i);
        }
        // R.layout.adapters_cabselection_row is a LinearLayout(with green
        // background(#99cc00)) that wraps an ImageView and a TextView
        mAdapter = new SelectionAdapter(this,
                R.layout.adapters_cabselection_row, R.id.the_text, mItems);
        setListAdapter(mAdapter);
        getListView().setChoiceMode(ListView.CHOICE_MODE_MULTIPLE_MODAL);
        getListView().setMultiChoiceModeListener(new MultiChoiceModeListener() {

            private int nr = 0;

            @Override
            public boolean onCreateActionMode(ActionMode mode, Menu menu) {
                MenuInflater inflater = getMenuInflater();
                inflater.inflate(R.menu.cabselection_menu, menu);
                return true;
            }

            @Override
            public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
                return false;
            }

            @Override
            public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
                StringBuilder sb = new StringBuilder();
                Set<Integer> positions = mAdapter.getCurrentCheckedPosition();
                for (Integer pos : positions) {
                    sb.append(" " + pos + ",");
                }               
                switch (item.getItemId()) {
                case R.id.edit_entry:
                    Toast.makeText(CABSelection.this, "Edited entries: " + sb.toString(),
                            Toast.LENGTH_SHORT).show();
                    break;
                case R.id.delete_entry:
                    Toast.makeText(CABSelection.this, "Deleted entries : " + sb.toString(),
                            Toast.LENGTH_SHORT).show();
                    break;
                case R.id.finish_it:
                    nr = 0;
                    mAdapter.clearSelection();
                    Toast.makeText(CABSelection.this, "Finish the CAB!",
                            Toast.LENGTH_SHORT).show();
                    mode.finish();
                }
                return false;
            }

            @Override
            public void onDestroyActionMode(ActionMode mode) {
                nr = 0;
                mAdapter.clearSelection();
            }

            @Override
            public void onItemCheckedStateChanged(ActionMode mode,
                    int position, long id, boolean checked) {
                if (checked) {
                    nr++;
                    mAdapter.setNewSelection(position, checked);                    
                } else {
                    nr--;
                    mAdapter.removeSelection(position);                 
                }
                mode.setTitle(nr + " rows selected!");

            }

        });
    }

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        l.setItemChecked(position, !mAdapter.isPositionChecked(position));
    }

    private class SelectionAdapter extends ArrayAdapter<String> {

        private HashMap<Integer, Boolean> mSelection = new HashMap<Integer, Boolean>();

        public SelectionAdapter(Context context, int resource,
                int textViewResourceId, List<String> objects) {
            super(context, resource, textViewResourceId, objects);
        }

        public void setNewSelection(int position, boolean value) {
            mSelection.put(position, value);
            notifyDataSetChanged();
        }

        public boolean isPositionChecked(int position) {
            Boolean result = mSelection.get(position);
            return result == null ? false : result;
        }

        public Set<Integer> getCurrentCheckedPosition() {
            return mSelection.keySet();
        }

        public void removeSelection(int position) {
            mSelection.remove(position);
            notifyDataSetChanged();
        }

        public void clearSelection() {
            mSelection = new HashMap<Integer, Boolean>();
            notifyDataSetChanged();
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View v = super.getView(position, convertView, parent);//let the adapter handle setting up the row views
            v.setBackgroundColor(Color.parseColor("#99cc00")); //default color
            if (mSelection.get(position) != null) {
                v.setBackgroundColor(Color.RED);// this is a selected position so make it red
            }
            return v;
        }

    }

}

The R.layout.adapters_cabselection_row is a custom layout for the row(a very simple one) with a green background:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#99cc00" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="https://stackoverflow.com/questions/10598348/@drawable/ic_launcher" />

    <TextView
        android:id="@+id/the_text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#ffffff"
        android:textSize="17sp"
        android:textStyle="bold" />

</LinearLayout>

R.menu.cabselection_menu is a menu file with 3 options(edit, delete, finish the CAB) which don’t do anything except pop a Toast with a message regarding the rows selected:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android" >

    <item
        android:id="@+id/edit_entry"
        android:icon="@android:drawable/ic_menu_edit"
        android:title="Edit!"/>
    <item
        android:id="@+id/delete_entry"
        android:icon="@android:drawable/ic_menu_delete"
        android:title="Delete!"/>
    <item
        android:id="@+id/finish_it"
        android:icon="@android:drawable/ic_menu_crop"
        android:title="Get me out!"/>

</menu>

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