Question

I have a custom SimpleCursorAdapter in a DialogFragment, and I am having trouble understanding the use of setTag and getTag. From my LogCat output, it seems that I am setting tag on a LinearLayout and trying to retrieve the tag from a Button. How can I target the right component to access the tag in the ClickListener?

    @Override
    public View getView(final int position, View convertView, final ViewGroup parent) {
        if (mCursor.moveToPosition(position)) {
            ViewHolder holder;
            final String label;
            final int label_index = mCursor.getColumnIndex(ProfilesColumns.USERNAME);
            label = mCursor.getString(label_index);

            if (convertView == null) {
                convertView = mInflater.inflate(layout, null);

                holder = new ViewHolder();
                holder.name = (Button) convertView.findViewById(R.id.title);
                holder.logout = (Button) convertView.findViewById(R.id.logout);
                holder.id = getItemId(position);
                convertView.setTag(holder);
                Log.d(DEBUG_TAG, "getView view " + convertView);//Returns LinearLayout
            } else {
                holder = (ViewHolder) convertView.getTag();
            }

            holder.logout.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(final View v) {
                    ViewHolder holder;
                    if (v == null) {
                        Log.d(DEBUG_TAG, "logout view null ");
                    } else {
                        Log.d(DEBUG_TAG, "logout view " + v);//Returns Button
                        holder = (ViewHolder) v.getTag();
                        if (holder == null) {
                            Log.d(DEBUG_TAG, "logout holder null ");
                        } else {
                            Log.d(DEBUG_TAG, "logout holder.id   " + holder.id);
                            String[] argument = { "" + holder.id };
                            ContentResolver cr = getActivity().getContentResolver();
                            int count = cr.delete(ProfileProvider.URI_LOADEDPROFILETABLE, CommonDatabaseHelper._ID
                                    + "=?", argument);
                            Log.d(DEBUG_TAG, "logout count       " + count);
                        }
                    }
                }
            });
        }
        return convertView;

    }

Here is the the layout, profileselect_list_item:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="0dp" >

<Button
    android:id="@+id/title"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1" />

<Button
    android:id="@+id/logout"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/logout" />

</LinearLayout>

Answer 1

The short answer is that you have not used setTag() on the Buttons, you only used it on its parent the LinearLayout. So inside your OnClickListener change this:

holder = (ViewHolder) v.getTag();

to:

holder = (ViewHolder) ((View) v.getParent()).getTag();

Also this line:

holder.id = getItemId(position);

changes for each row, while the OnClickListener doesn’t. You should move the above line outside of if(convertView == null) and move the OnClickListener inside.

---

The longer answer
You are extending a CursorAdapter, they have three great methods newView(), bindView(), and getView().

• newView() creates the new Views. Override this method and move all of your if(convertView == null) { ... } code into here.

• bindView() has direct access to the Cursor. It seems the SimpleCursorAdapter’s default method takes care of this for you…

• Overriding getView() is not always necessary because of the awesomeness of newView() and bindView().