/*
* Copyright (C) 2015 Google Inc. All Rights Reserved.
*
* 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 com.example.google.playservices.placecomplete;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.PendingResult;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.common.data.DataBufferUtils;
import com.google.android.gms.location.places.AutocompleteFilter;
import com.google.android.gms.location.places.AutocompletePrediction;
import com.google.android.gms.location.places.AutocompletePredictionBuffer;
import com.google.android.gms.location.places.Places;
import com.google.android.gms.maps.model.LatLngBounds;
import com.example.android.common.logger.Log;
import android.content.Context;
import android.graphics.Typeface;
import android.text.style.CharacterStyle;
import android.text.style.StyleSpan;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.concurrent.TimeUnit;
/**
* Adapter that handles Autocomplete requests from the Places Geo Data API.
* {@link AutocompletePrediction} results from the API are frozen and stored directly in this
* adapter. (See {@link AutocompletePrediction#freeze()}.)
* <p>
* Note that this adapter requires a valid {@link com.google.android.gms.common.api.GoogleApiClient}.
* The API client must be maintained in the encapsulating Activity, including all lifecycle and
* connection states. The API client must be connected with the {@link Places#GEO_DATA_API} API.
*/
public class PlaceAutocompleteAdapter
extends ArrayAdapter<AutocompletePrediction> implements Filterable {
private static final String TAG = "PlaceAutocompleteAdapter";
private static final CharacterStyle STYLE_BOLD = new StyleSpan(Typeface.BOLD);
/**
* Current results returned by this adapter.
*/
private ArrayList<AutocompletePrediction> mResultList;
/**
* Handles autocomplete requests.
*/
private GoogleApiClient mGoogleApiClient;
/**
* The bounds used for Places Geo Data autocomplete API requests.
*/
private LatLngBounds mBounds;
/**
* The autocomplete filter used to restrict queries to a specific set of place types.
*/
private AutocompleteFilter mPlaceFilter;
/**
* Initializes with a resource for text rows and autocomplete query bounds.
*
* @see android.widget.ArrayAdapter#ArrayAdapter(android.content.Context, int)
*/
public PlaceAutocompleteAdapter(Context context, GoogleApiClient googleApiClient,
LatLngBounds bounds, AutocompleteFilter filter) {
super(context, android.R.layout.simple_expandable_list_item_2, android.R.id.text1);
mGoogleApiClient = googleApiClient;
mBounds = bounds;
mPlaceFilter = filter;
}
/**
* Sets the bounds for all subsequent queries.
*/
public void setBounds(LatLngBounds bounds) {
mBounds = bounds;
}
/**
* Returns the number of results received in the last autocomplete query.
*/
@Override
public int getCount() {
return mResultList.size();
}
/**
* Returns an item from the last autocomplete query.
*/
@Override
public AutocompletePrediction getItem(int position) {
return mResultList.get(position);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = super.getView(position, convertView, parent);
// Sets the primary and secondary text for a row.
// Note that getPrimaryText() and getSecondaryText() return a CharSequence that may contain
// styling based on the given CharacterStyle.
AutocompletePrediction item = getItem(position);
TextView textView1 = (TextView) row.findViewById(android.R.id.text1);
TextView textView2 = (TextView) row.findViewById(android.R.id.text2);
textView1.setText(item.getPrimaryText(STYLE_BOLD));
textView2.setText(item.getSecondaryText(STYLE_BOLD));
return row;
}
/**
* Returns the filter for the current set of autocomplete results.
*/
@Override
public Filter getFilter() {
return new Filter() {
@Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults results = new FilterResults();
// We need a separate list to store the results, since
// this is run asynchronously.
ArrayList<AutocompletePrediction> filterData = new ArrayList<>();
// Skip the autocomplete query if no constraints are given.
if (constraint != null) {
// Query the autocomplete API for the (constraint) search string.
filterData = getAutocomplete(constraint);
}
results.values = filterData;
if (filterData != null) {
results.count = filterData.size();
} else {
results.count = 0;
}
return results;
}
@Override
protected void publishResults(CharSequence constraint, FilterResults results) {
if (results != null && results.count > 0) {
// The API returned at least one result, update the data.
mResultList = (ArrayList<AutocompletePrediction>) results.values;
notifyDataSetChanged();
} else {
// The API did not return any results, invalidate the data set.
notifyDataSetInvalidated();
}
}
@Override
public CharSequence convertResultToString(Object resultValue) {
// Override this method to display a readable result in the AutocompleteTextView
// when clicked.
if (resultValue instanceof AutocompletePrediction) {
return ((AutocompletePrediction) resultValue).getFullText(null);
} else {
return super.convertResultToString(resultValue);
}
}
};
}
/**
* Submits an autocomplete query to the Places Geo Data Autocomplete API.
* Results are returned as frozen AutocompletePrediction objects, ready to be cached.
* objects to store the Place ID and description that the API returns.
* Returns an empty list if no results were found.
* Returns null if the API client is not available or the query did not complete
* successfully.
* This method MUST be called off the main UI thread, as it will block until data is returned
* from the API, which may include a network request.
*
* @param constraint Autocomplete query string
* @return Results from the autocomplete API or null if the query was not successful.
* @see Places#GEO_DATA_API#getAutocomplete(CharSequence)
* @see AutocompletePrediction#freeze()
*/
private ArrayList<AutocompletePrediction> getAutocomplete(CharSequence constraint) {
if (mGoogleApiClient.isConnected()) {
Log.i(TAG, "Starting autocomplete query for: " + constraint);
// Submit the query to the autocomplete API and retrieve a PendingResult that will
// contain the results when the query completes.
PendingResult<AutocompletePredictionBuffer> results =
Places.GeoDataApi
.getAutocompletePredictions(mGoogleApiClient, constraint.toString(),
mBounds, mPlaceFilter);
// This method should have been called off the main UI thread. Block and wait for at most 60s
// for a result from the API.
AutocompletePredictionBuffer autocompletePredictions = results
.await(60, TimeUnit.SECONDS);
// Confirm that the query completed successfully, otherwise return null
final Status status = autocompletePredictions.getStatus();
if (!status.isSuccess()) {
Toast.makeText(getContext(), "Error contacting API: " + status.toString(),
Toast.LENGTH_SHORT).show();
Log.e(TAG, "Error getting autocomplete prediction API call: " + status.toString());
autocompletePredictions.release();
return null;
}
Log.i(TAG, "Query completed. Received " + autocompletePredictions.getCount()
+ " predictions.");
// Freeze the results immutable representation that can be stored safely.
return DataBufferUtils.freezeAndClose(autocompletePredictions);
}
Log.e(TAG, "Google API client is not connected for autocomplete query.");
return null;
}
}