DynamicSpinner.java

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * 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 net.redgeek.android.eventrend.util;

import java.util.ArrayList;
import java.util.List;

import android.content.Context;
import android.util.AttributeSet;
import android.widget.ArrayAdapter;
import android.widget.Spinner;

/**
 * Dynamic spinner convenience class, allows for easy adding of items and
 * clearing of a Spinner view.
 * 
 * @author barclay
 * 
 */
public class DynamicSpinner extends Spinner {
  private List<Long> mSpinnerAdapterMapping = new ArrayList<Long>();
  private ArrayAdapter<CharSequence> mSpinnerAdapter;
  private Context mCtx;

  /**
   * Constructor. Creates an empty dynamic spinner associated with the context
   * of <code>context</code>.
   * 
   * @param context
   *          The Context responsible for this view.
   */
  public DynamicSpinner(Context context) {
    super(context);
    setup(context);
  }

  /**
   * Constructor. Creates an empty dynamic spinner associated with the context
   * of <code>context</code>. <br>
   * <strong>attrs is currently ignored and only present to satisfy the same
   * constructor set as a Spinner.</strong>
   * 
   * @param context
   *          The Context responsible for this view.
   * @param attrs
   *          (Ignored.)
   */
  public DynamicSpinner(Context context, AttributeSet attrs) {
    super(context);
    setup(context);
  }

  /**
   * Constructor. Creates an empty dynamic spinner associated with the context
   * of <code>context</code>. <br>
   * <strong>attrs and defStyle are currently ignored and only present to
   * satisfy the same constructor set as a Spinner.</strong>
   * 
   * @param context
   *          The Context responsible for this view.
   * @param attrs
   *          (Ignored.)
   * @param defStyle
   *          (Ignored.)
   */
  public DynamicSpinner(Context context, AttributeSet attrs, int defStyle) {
    super(context);
    setup(context);
  }

  /**
   * Initialization common to all constructors. Stores away the context,
   * allocates and ArrayAdapter for the Spinner, sets it's resources, and sets
   * the adapter for the Spinner.
   * 
   * @param context
   *          The context associated with this view.
   */
  private void setup(Context context) {
    mCtx = context;
    mSpinnerAdapter = new ArrayAdapter<CharSequence>(mCtx,
        android.R.layout.simple_spinner_item);
    mSpinnerAdapter
        .setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    setAdapter(mSpinnerAdapter);
  }

  /**
   * Appends a menu item to the Spinner.
   * 
   * @param text
   *          The text for the menu item.
   * @param mapping
   *          A number associated with the entry, can be arbitrary.
   * @see #getMappingFromPosition(int position)
   */
  public void addSpinnerItem(String text, Long mapping) {
    CharSequence textHolder = "" + text;
    mSpinnerAdapter.add(textHolder);
    mSpinnerAdapterMapping.add(mapping);
  }

  /**
   * Removes all spinner menu items (and associated mappings) from the Spinner.
   */
  public void clearSpinnerItems() {
    mSpinnerAdapter.clear();
    mSpinnerAdapterMapping.clear();
  }

  /**
   * Returns the mapping associated with the menu item at <code>position</code>.
   * 
   * @param position
   * @return
   * @see #addSpinnerItem(String, Long)
   */
  public long getMappingFromPosition(int position) {
    return Long.valueOf(mSpinnerAdapterMapping.get(position));
  }

  /**
   * Sets the Spiner to visible or invisible.
   * 
   * @param b
   *          boolean, true or false
   */
  public void setVisibility(boolean b) {
    setVisibility(b);
  }
}