WheelViewAdapter.java

/*
 * android-spinnerwheel
 * https://github.com/ai212983/android-spinnerwheel
 *
 * based on
 *
 * Android Wheel Control.
 * https://code.google.com/p/android-wheel/
 *
 * Copyright 2011 Yuri Kanivets
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.droidplanner.android.view.spinnerWheel.adapters;

import android.database.DataSetObserver;
import android.view.View;
import android.view.ViewGroup;

/**
 * Wheel items adapter interface
 */
public interface WheelViewAdapter {
	/**
	 * Gets items count
	 * 
	 * @return the count of spinnerwheel items
	 */
	int getItemsCount();

	/**
	 * Get a View that displays the data at the specified position in the data
	 * set
	 * 
	 * @param index
	 *            the item index
	 * @param convertView
	 *            the old view to reuse if possible
	 * @param parent
	 *            the parent that this view will eventually be attached to
	 * @return the spinnerwheel item View
	 */
	View getItem(int index, View convertView, ViewGroup parent);

	/**
	 * Get a View that displays an empty spinnerwheel item placed before the
	 * first or after the last spinnerwheel item.
	 * 
	 * @param convertView
	 *            the old view to reuse if possible
	 * @param parent
	 *            the parent that this view will eventually be attached to
	 * @return the empty item View
	 */
	View getEmptyItem(View convertView, ViewGroup parent);

	/**
	 * Register an observer that is called when changes happen to the data used
	 * by this adapter.
	 * 
	 * @param observer
	 *            the observer to be registered
	 */
	void registerDataSetObserver(DataSetObserver observer);

	/**
	 * Unregister an observer that has previously been registered
	 * 
	 * @param observer
	 *            the observer to be unregistered
	 */
	void unregisterDataSetObserver(DataSetObserver observer);
}