text: /*
   * Copyright 2010-present Facebook.
   *
   * 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.
   */
  
  #import "FBGraphObject.h"
  #import "FBSession.h"
  #import "FBViewController.h"
  
  @protocol FBGraphObjectPickerDelegate;
  
  /*!
   @class FBGraphObjectPickerViewController
  
   @abstract
   The `FBGraphObjectPickerViewController` class is an abstract controller object that
   manages the user interface for displaying and selecting a collection of graph objects.
  
   @discussion
   When the `FBGraphObjectPickerViewController` view loads it creates a `UITableView`
   object where the graph objects defined by a concrete subclass will be displayed. You
   can access this view through the `tableView` property.
  
   The `delegate` property may be set to an object that conforms to the <FBGraphObjectPickerDelegate>
   protocol. The `delegate` object will receive updates related to object selection and
   data changes. The delegate can also be used to filter the objects to display in the
   picker.
   */
  @interface FBGraphObjectPickerViewController : FBViewController
  
  /*!
   @abstract
   Returns an outlet for the spinner used in the view controller.
   */
  @property (nonatomic, retain) IBOutlet UIActivityIndicatorView *spinner;
  
  /*!
   @abstract
   Returns an outlet for the table view managed by the view controller.
   */
  @property (nonatomic, retain) IBOutlet UITableView *tableView;
  
  /*!
   @abstract
   Addtional fields to fetch when making the Graph API call to get graph object data.
   */
  @property (nonatomic, copy) NSSet *fieldsForRequest;
  
  /*!
   @abstract
   A Boolean value that indicates whether pictures representing the graph object are displayed.
   Defaults to YES.
   */
  @property (nonatomic) BOOL itemPicturesEnabled;
  
  /*!
   @abstract
   The session that is used in the request for the graph object data.
   */
  @property (nonatomic, retain) FBSession *session;
  
  /*!
   @abstract
   Clears the current selection, so the picker is ready for a fresh use.
   */
  - (void)clearSelection;
  
  /*!
   @abstract
   Initiates a query to get the graph object data.
  
  
   @discussion
   A cached copy will be returned if available. The cached view is temporary until a fresh copy is
   retrieved from the server. It is legal to call this more than once.
   */
  - (void)loadData;
  
  /*!
   @abstract
   Updates the view locally without fetching data from the server or from cache.
  
   @discussion
   Use this if the filter or sort (if applicable) properties change. This may affect the
   order or display of information.
   */
  - (void)updateView;
  
  @end
  
  /*!
   @protocol
  
   @abstract
   The `FBGraphObjectPickerDelegate` protocol defines the methods used to receive event
   notifications and allow for deeper control of the <FBGraphObjectPickerViewController>
   view.
   */
  @protocol FBGraphObjectPickerDelegate <FBViewControllerDelegate>
  @optional
  
  /*!
   @abstract
   Tells the delegate that data has been loaded.
  
   @discussion
   The <FBGraphObjectPickerViewController> object's `tableView` property is automatically
   reloaded when this happens. However, if another table view, for example the
   `UISearchBar` is showing data, then it may also need to be reloaded.
  
   @param graphObjectPicker   The graph object picker view controller whose data changed.
   */
  - (void)graphObjectPickerViewControllerDataDidChange:(FBGraphObjectPickerViewController *)graphObjectPicker;
  
  /*!
   @abstract
   Tells the delegate that the selection has changed.
  
   @param graphObjectPicker   The graph object picker view controller whose selection changed.
   */
  - (void)graphObjectPickerViewControllerSelectionDidChange:(FBGraphObjectPickerViewController *)graphObjectPicker;
  
  /*!
   @abstract
   Asks the delegate whether to include a graph object in the list.
  
   @discussion
   This can be used to implement a search bar that filters the graph object list.
  
   @param graphObjectPicker   The graph object picker view controller that is requesting this information.
   @param object              An <FBGraphObject> object
   */
  - (BOOL)graphObjectPickerViewController:(FBGraphObjectPickerViewController *)graphObjectPicker
                 shouldIncludeGraphObject:(id<FBGraphObject>)object;
  
  /*!
   @abstract
   Called if there is a communication error.
  
   @param graphObjectPicker   The graph object picker view controller that encountered the error.
   @param error               An error object containing details of the error.
   */
  - (void)graphObjectPickerViewController:(FBGraphObjectPickerViewController *)graphObjectPicker
                              handleError:(NSError *)error;
  
  @end
  