package eu.ttbox.androgister.domain.core; import android.content.Context; import android.database.Cursor; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import de.greenrobot.dao.query.LazyList; import eu.ttbox.androgister.domain.DomainModel; public abstract class LazyListAdapter<T extends DomainModel, VIEW_HOLDER> extends BaseAdapter { private int mLayout; private int mDropDownLayout; private LayoutInflater mInflater; protected boolean mDataValid; protected LazyList<T> lazyList; protected Context context; public LazyListAdapter(Context context, int layout, LazyList<T> lazyList) { mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); mLayout = mDropDownLayout = layout; this.lazyList = lazyList; this.mDataValid = lazyList != null; this.context = context; } /** * Swap in a new Cursor, returning the old Cursor. Unlike * {@link #changeCursor(Cursor)}, the returned old Cursor is <em>not</em> * closed. * * @param newCursor The new cursor to be used. * @return Returns the previously set Cursor, or null if there wasa not one. * If the given new Cursor is the same instance is the previously set * Cursor, null is also returned. */ public LazyList<T> swapCursor(LazyList<T> newCursor) { if (newCursor == lazyList) { return null; } LazyList<T> oldCursor = lazyList; // Unregister cursor listener // Swap lazyList = newCursor; if (newCursor!=null) { mDataValid = true; // notify the observers about the new cursor notifyDataSetChanged(); } else { mDataValid = false; // notify the observers about the lack of a data set notifyDataSetInvalidated(); } return oldCursor; } public void changeCursor( LazyList<T> cursor) { LazyList<T> old = swapCursor(cursor); if (old != null) { old.close(); } } public void setDropDownViewResource(int dropDownLayout) { this.mDropDownLayout = dropDownLayout; } public void close() { lazyList.close(); } /** * Returns the list. * * @return the list. */ public LazyList<T> getLazyList() { return lazyList; } /** * @see android.widget.ListAdapter#getCount() */ @Override public int getCount() { if (mDataValid && lazyList != null) { return lazyList.size(); } else { return 0; } } /** * @see android.widget.ListAdapter#getItem(int) */ @Override public T getItem(int position) { if (mDataValid && lazyList != null) { return lazyList.get(position); } else { return null; } } /** */ @Override public long getItemId(int position) { if (mDataValid && lazyList != null) { T item = lazyList.get(position); if (item != null) { return item.getId(); } else { return 0; } } else { return 0; } } @Override public boolean hasStableIds() { return true; } /** * @see android.widget.ListAdapter#getView(int, View, ViewGroup) */ public View getView(int position, View convertView, ViewGroup parent) { if (!mDataValid) { throw new IllegalStateException("this should only be called when lazylist is populated"); } T item = lazyList.get(position); if (item == null) { throw new IllegalStateException("Item at position " + position + " is null"); } View v; if (convertView == null) { v = newView(context, item, parent, mLayout); } else { v = convertView; } bindView(v, context, item); return v; } @Override public View getDropDownView(int position, View convertView, ViewGroup parent) { if (mDataValid) { T item = lazyList.get(position); View v; if (convertView == null) { v = newDropDownView(context, item, parent); } else { v = convertView; } bindView(v, context, item); return v; } else { return null; } } /** * Makes a new view to hold the data contained in the item. * * @param context * Interface to application's global information * @param item * The object that contains the data * @param parent * The parent to which the new view is attached to * @return the newly created view. */ public View newView(Context context, T item, ViewGroup parent, int layoutResourceId) { View view = mInflater.inflate(layoutResourceId, parent, false); VIEW_HOLDER holder = newViewHolder(view, context, item, parent); view.setTag(holder); return view; } public abstract VIEW_HOLDER newViewHolder(View view, Context context, T item, ViewGroup parent); /** * Makes a new drop down view to hold the data contained in the item. * * @param context * Interface to application's global information * @param item * The object that contains the data * @param parent * The parent to which the new view is attached to * @return the newly created view. */ public View newDropDownView(Context context, T item, ViewGroup parent) { return newView(context, item, parent, mDropDownLayout); } /** * Bind an existing view to the data data contained in the item. * * @param view * Existing view, returned earlier by newView * @param context * Interface to application's global information * @param cursor * The object that contains the data */ @SuppressWarnings("unchecked") public void bindView(View view, Context context, T item) { VIEW_HOLDER holder = (VIEW_HOLDER) view.getTag(); bindView(view, holder, context, item); } public abstract void bindView(View view, VIEW_HOLDER holder, Context context, T item); }