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A library jar that provides APIs for Applications written for the Google Android Platform.

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/*
 * Copyright (C) 2006 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 android.widget;

import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

/**
 * A concrete BaseAdapter that is backed by an array of arbitrary
 * objects.  By default this class expects that the provided resource id references
 * a single TextView.  If you want to use a more complex layout, use the constructors that
 * also takes a field id.  That field id should reference a TextView in the larger layout
 * resource.
 *
 * 

However the TextView is referenced, it will be filled with the toString() of each object in * the array. You can add lists or arrays of custom objects. Override the toString() method * of your objects to determine what text will be displayed for the item in the list. * *

To use something other than TextViews for the array display, for instance, ImageViews, * or to have some of data besides toString() results fill the views, * override {@link #getView(int, View, ViewGroup)} to return the type of view you want. */ public class ArrayAdapter extends BaseAdapter implements Filterable { /** * Contains the list of objects that represent the data of this ArrayAdapter. * The content of this list is referred to as "the array" in the documentation. */ private List mObjects; /** * Lock used to modify the content of {@link #mObjects}. Any write operation * performed on the array should be synchronized on this lock. This lock is also * used by the filter (see {@link #getFilter()} to make a synchronized copy of * the original array of data. */ private final Object mLock = new Object(); /** * The resource indicating what views to inflate to display the content of this * array adapter. */ private int mResource; /** * The resource indicating what views to inflate to display the content of this * array adapter in a drop down widget. */ private int mDropDownResource; /** * If the inflated resource is not a TextView, {@link #mFieldId} is used to find * a TextView inside the inflated views hierarchy. This field must contain the * identifier that matches the one defined in the resource file. */ private int mFieldId = 0; /** * Indicates whether or not {@link #notifyDataSetChanged()} must be called whenever * {@link #mObjects} is modified. */ private boolean mNotifyOnChange = true; private Context mContext; // A copy of the original mObjects array, initialized from and then used instead as soon as // the mFilter ArrayFilter is used. mObjects will then only contain the filtered values. private ArrayList mOriginalValues; private ArrayFilter mFilter; private LayoutInflater mInflater; /** * Constructor * * @param context The current context. * @param resource The resource ID for a layout file containing a TextView to use when * instantiating views. */ public ArrayAdapter(Context context, int resource) { init(context, resource, 0, new ArrayList()); } /** * Constructor * * @param context The current context. * @param resource The resource ID for a layout file containing a layout to use when * instantiating views. * @param textViewResourceId The id of the TextView within the layout resource to be populated */ public ArrayAdapter(Context context, int resource, int textViewResourceId) { init(context, resource, textViewResourceId, new ArrayList()); } /** * Constructor * * @param context The current context. * @param resource The resource ID for a layout file containing a TextView to use when * instantiating views. * @param objects The objects to represent in the ListView. */ public ArrayAdapter(Context context, int resource, T[] objects) { init(context, resource, 0, Arrays.asList(objects)); } /** * Constructor * * @param context The current context. * @param resource The resource ID for a layout file containing a layout to use when * instantiating views. * @param textViewResourceId The id of the TextView within the layout resource to be populated * @param objects The objects to represent in the ListView. */ public ArrayAdapter(Context context, int resource, int textViewResourceId, T[] objects) { init(context, resource, textViewResourceId, Arrays.asList(objects)); } /** * Constructor * * @param context The current context. * @param resource The resource ID for a layout file containing a TextView to use when * instantiating views. * @param objects The objects to represent in the ListView. */ public ArrayAdapter(Context context, int resource, List objects) { init(context, resource, 0, objects); } /** * Constructor * * @param context The current context. * @param resource The resource ID for a layout file containing a layout to use when * instantiating views. * @param textViewResourceId The id of the TextView within the layout resource to be populated * @param objects The objects to represent in the ListView. */ public ArrayAdapter(Context context, int resource, int textViewResourceId, List objects) { init(context, resource, textViewResourceId, objects); } /** * Adds the specified object at the end of the array. * * @param object The object to add at the end of the array. */ public void add(T object) { synchronized (mLock) { if (mOriginalValues != null) { mOriginalValues.add(object); } else { mObjects.add(object); } } if (mNotifyOnChange) notifyDataSetChanged(); } /** * Adds the specified Collection at the end of the array. * * @param collection The Collection to add at the end of the array. */ public void addAll(Collection collection) { synchronized (mLock) { if (mOriginalValues != null) { mOriginalValues.addAll(collection); } else { mObjects.addAll(collection); } } if (mNotifyOnChange) notifyDataSetChanged(); } /** * Adds the specified items at the end of the array. * * @param items The items to add at the end of the array. */ public void addAll(T ... items) { synchronized (mLock) { if (mOriginalValues != null) { Collections.addAll(mOriginalValues, items); } else { Collections.addAll(mObjects, items); } } if (mNotifyOnChange) notifyDataSetChanged(); } /** * Inserts the specified object at the specified index in the array. * * @param object The object to insert into the array. * @param index The index at which the object must be inserted. */ public void insert(T object, int index) { synchronized (mLock) { if (mOriginalValues != null) { mOriginalValues.add(index, object); } else { mObjects.add(index, object); } } if (mNotifyOnChange) notifyDataSetChanged(); } /** * Removes the specified object from the array. * * @param object The object to remove. */ public void remove(T object) { synchronized (mLock) { if (mOriginalValues != null) { mOriginalValues.remove(object); } else { mObjects.remove(object); } } if (mNotifyOnChange) notifyDataSetChanged(); } /** * Remove all elements from the list. */ public void clear() { synchronized (mLock) { if (mOriginalValues != null) { mOriginalValues.clear(); } else { mObjects.clear(); } } if (mNotifyOnChange) notifyDataSetChanged(); } /** * Sorts the content of this adapter using the specified comparator. * * @param comparator The comparator used to sort the objects contained * in this adapter. */ public void sort(Comparator comparator) { synchronized (mLock) { if (mOriginalValues != null) { Collections.sort(mOriginalValues, comparator); } else { Collections.sort(mObjects, comparator); } } if (mNotifyOnChange) notifyDataSetChanged(); } /** * {@inheritDoc} */ @Override public void notifyDataSetChanged() { super.notifyDataSetChanged(); mNotifyOnChange = true; } /** * Control whether methods that change the list ({@link #add}, * {@link #insert}, {@link #remove}, {@link #clear}) automatically call * {@link #notifyDataSetChanged}. If set to false, caller must * manually call notifyDataSetChanged() to have the changes * reflected in the attached view. * * The default is true, and calling notifyDataSetChanged() * resets the flag to true. * * @param notifyOnChange if true, modifications to the list will * automatically call {@link * #notifyDataSetChanged} */ public void setNotifyOnChange(boolean notifyOnChange) { mNotifyOnChange = notifyOnChange; } private void init(Context context, int resource, int textViewResourceId, List objects) { mContext = context; mInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); mResource = mDropDownResource = resource; mObjects = objects; mFieldId = textViewResourceId; } /** * Returns the context associated with this array adapter. The context is used * to create views from the resource passed to the constructor. * * @return The Context associated with this adapter. */ public Context getContext() { return mContext; } /** * {@inheritDoc} */ public int getCount() { return mObjects.size(); } /** * {@inheritDoc} */ public T getItem(int position) { return mObjects.get(position); } /** * Returns the position of the specified item in the array. * * @param item The item to retrieve the position of. * * @return The position of the specified item. */ public int getPosition(T item) { return mObjects.indexOf(item); } /** * {@inheritDoc} */ public long getItemId(int position) { return position; } /** * {@inheritDoc} */ public View getView(int position, View convertView, ViewGroup parent) { return createViewFromResource(position, convertView, parent, mResource); } private View createViewFromResource(int position, View convertView, ViewGroup parent, int resource) { View view; TextView text; if (convertView == null) { view = mInflater.inflate(resource, parent, false); } else { view = convertView; } try { if (mFieldId == 0) { // If no custom field is assigned, assume the whole resource is a TextView text = (TextView) view; } else { // Otherwise, find the TextView field within the layout text = (TextView) view.findViewById(mFieldId); } } catch (ClassCastException e) { Log.e("ArrayAdapter", "You must supply a resource ID for a TextView"); throw new IllegalStateException( "ArrayAdapter requires the resource ID to be a TextView", e); } T item = getItem(position); if (item instanceof CharSequence) { text.setText((CharSequence)item); } else { text.setText(item.toString()); } return view; } /** *

Sets the layout resource to create the drop down views.

* * @param resource the layout resource defining the drop down views * @see #getDropDownView(int, android.view.View, android.view.ViewGroup) */ public void setDropDownViewResource(int resource) { this.mDropDownResource = resource; } /** * {@inheritDoc} */ @Override public View getDropDownView(int position, View convertView, ViewGroup parent) { return createViewFromResource(position, convertView, parent, mDropDownResource); } /** * Creates a new ArrayAdapter from external resources. The content of the array is * obtained through {@link android.content.res.Resources#getTextArray(int)}. * * @param context The application's environment. * @param textArrayResId The identifier of the array to use as the data source. * @param textViewResId The identifier of the layout used to create views. * * @return An ArrayAdapter. */ public static ArrayAdapter createFromResource(Context context, int textArrayResId, int textViewResId) { CharSequence[] strings = context.getResources().getTextArray(textArrayResId); return new ArrayAdapter(context, textViewResId, strings); } /** * {@inheritDoc} */ public Filter getFilter() { if (mFilter == null) { mFilter = new ArrayFilter(); } return mFilter; } /** *

An array filter constrains the content of the array adapter with * a prefix. Each item that does not start with the supplied prefix * is removed from the list.

*/ private class ArrayFilter extends Filter { @Override protected FilterResults performFiltering(CharSequence prefix) { FilterResults results = new FilterResults(); if (mOriginalValues == null) { synchronized (mLock) { mOriginalValues = new ArrayList(mObjects); } } if (prefix == null || prefix.length() == 0) { ArrayList list; synchronized (mLock) { list = new ArrayList(mOriginalValues); } results.values = list; results.count = list.size(); } else { String prefixString = prefix.toString().toLowerCase(); ArrayList values; synchronized (mLock) { values = new ArrayList(mOriginalValues); } final int count = values.size(); final ArrayList newValues = new ArrayList(); for (int i = 0; i < count; i++) { final T value = values.get(i); final String valueText = value.toString().toLowerCase(); // First match against the whole, non-splitted value if (valueText.startsWith(prefixString)) { newValues.add(value); } else { final String[] words = valueText.split(" "); final int wordCount = words.length; // Start at index 0, in case valueText starts with space(s) for (int k = 0; k < wordCount; k++) { if (words[k].startsWith(prefixString)) { newValues.add(value); break; } } } } results.values = newValues; results.count = newValues.size(); } return results; } @Override protected void publishResults(CharSequence constraint, FilterResults results) { //noinspection unchecked mObjects = (List) results.values; if (results.count > 0) { notifyDataSetChanged(); } else { notifyDataSetInvalidated(); } } } }




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