Gmail-like ListView with checkboxes (and using the ActionBar)

Question

I\'m trying to recreate what Google did with the ListView in the Gmail app. In particular, I would like to have each list item include a CheckBox and two TextViews (one on t

Answer 1

This will work in SDK 7 (android 2.1) and higher. (together with SherlockActionBar)

Totaly mimic gmail listbox experience.

I override onTouchEvent so press in the left corner side will activate selection mode; mutch better then trying to click on the tiny cheackbox.

I override performItemClick so pressing not in the left will act as a Regular press action.

I override setItemChecked so it will update mActionMode as needed.

public class SelectListView extends ListView {

    private SherlockFragmentActivity mActivity;
    ActionMode mActionMode;

      public SelectListView(Context context) {
    this( context, null, 0); 
}

public SelectListView(Context context, AttributeSet attrs) {   
    this( context, attrs, 0); 
}   


public SelectListView(Context context, AttributeSet attrs, int defStyle) {
    super( context, attrs, defStyle ); 
    setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
    mActivity = (SherlockFragmentActivity) context;
}

    @Override
    public boolean performItemClick(View view, int position, long id) {
        OnItemClickListener mOnItemClickListener = getOnItemClickListener();
        if (mOnItemClickListener != null) {
            playSoundEffect(SoundEffectConstants.CLICK);
            if (view != null)
                view.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_CLICKED);
            mOnItemClickListener.onItemClick(this, view, position, id);
            return true;
        }
        return false;
    }

    boolean mSelectionMode = false;
    int mStartPosition;

    @Override
    public boolean onTouchEvent(MotionEvent ev) {

        final int action = ev.getAction();
        final int x = (int) ev.getX();
        final int y = (int) ev.getY();

        if (action == MotionEvent.ACTION_DOWN && x < getWidth() / 7) {
            mSelectionMode = true;
            mStartPosition = pointToPosition(x, y);
        }
        if (!mSelectionMode)
            return super.onTouchEvent(ev);
        switch (action) {
        case MotionEvent.ACTION_DOWN:
            break;
        case MotionEvent.ACTION_MOVE:
            if (pointToPosition(x, y) != mStartPosition)
                mSelectionMode = false;
            break;
        case MotionEvent.ACTION_CANCEL:
        case MotionEvent.ACTION_UP:
        default:
            mSelectionMode = false;
            int mItemPosition = pointToPosition(x, y);
            if (mStartPosition != ListView.INVALID_POSITION)
                setItemChecked(mItemPosition, !isItemChecked(mItemPosition));
        }

        return true;
    }

    @Override
    public void setItemChecked(int position, boolean value) {
        super.setItemChecked(position, value);
        // boolean r = getAdapter().hasStableIds();
        int checkedCount = getCheckItemIds().length;

        if (checkedCount == 0) {
            if (mActionMode != null)
                mActionMode.finish();
            return;
        }
        if (mActionMode == null)
            mActionMode = mActivity.startActionMode(new ModeCallback());

        mActionMode.setTitle(checkedCount + " selected");

    }

    class ModeCallback implements ActionMode.Callback {

        @Override
        public boolean onCreateActionMode(ActionMode mode, Menu menu) {

            menu.add(getResources().getString(R.string.aBar_remove)).setIcon(R.drawable.ic_action_trash)
                    .setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);

            return true;
        }

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

        @Override
        public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
            Toast.makeText(mActivity, "Delted  items", Toast.LENGTH_SHORT).show();
            mode.finish();
            return true;
        }

        @Override
        public void onDestroyActionMode(ActionMode mode) {
            mActionMode = null;
            clearChecked();
        }

    }

    public void clearChecked() {
        SparseBooleanArray CItem = getCheckedItemPositions();
        for (int i = 0; i < CItem.size(); i++)
            if (CItem.valueAt(i))
                super.setItemChecked(CItem.keyAt(i), false);
    }

}

you can use any listbox adapter you need.

if you have a checkbox on your list_item_layout tou need to extent your adapter like this:

ArrayAdapter mAdapter = new ArrayAdapter(this, R.layout.simple_list_item_multiple_choice,
            R.id.text1, Cheeses.sCheeseStrings) {

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View v = super.getView(position, convertView, parent);
            CheckBox checkBox = (CheckBox) v.findViewById(R.id.CheckBox);
            checkBox.setChecked(((ListView)parent).isItemChecked(position));
            return v;
        }

    };

Don't forget to use android:background="?attr/activatedBackgroundIndicator" on your list_item_layout.xml