AFNetworkActivityIndicatorManager.h

// AFNetworkActivityIndicatorManager.h
//
// Copyright (c) 2011 Gowalla (http://gowalla.com/)
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// THE SOFTWARE.

#import <Foundation/Foundation.h>

#import <Availability.h>

#if defined(__IPHONE_OS_VERSION_MIN_REQUIRED)
#import <UIKit/UIKit.h>

/**
 `AFNetworkActivityIndicatorManager` manages the state of the network activity indicator in the status bar. When enabled, it will listen for notifications indicating that a network request operation has started or finished, and start or stop animating the indicator accordingly. The number of active requests is incremented and decremented much like a stack or a semaphore, and the activity indicator will animate so long as that number is greater than zero.

 You should enable the shared instance of `AFNetworkActivityIndicatorManager` when your application finishes launching. In `AppDelegate application:didFinishLaunchingWithOptions:` you can do so with the following code:

    [[AFNetworkActivityIndicatorManager sharedManager] setEnabled:YES];

 By setting `isNetworkActivityIndicatorVisible` to `YES` for `sharedManager`, the network activity indicator will show and hide automatically as requests start and finish. You should not ever need to call `incrementActivityCount` or `decrementActivityCount` yourself.

 See the Apple Human Interface Guidelines section about the Network Activity Indicator for more information:
 http://developer.apple.com/library/iOS/#documentation/UserExperience/Conceptual/MobileHIG/UIElementGuidelines/UIElementGuidelines.html#//apple_ref/doc/uid/TP40006556-CH13-SW44
 */
@interface AFNetworkActivityIndicatorManager : NSObject

/**
 A Boolean value indicating whether the manager is enabled.

 @discussion If YES, the manager will change status bar network activity indicator according to network operation notifications it receives. The default value is NO.
 */
@property (nonatomic, assign, getter = isEnabled) BOOL enabled;

/**
 A Boolean value indicating whether the network activity indicator is currently displayed in the status bar.
 */
@property (readonly, nonatomic, assign) BOOL isNetworkActivityIndicatorVisible;

/**
 Returns the shared network activity indicator manager object for the system.

 @return The systemwide network activity indicator manager.
 */
+ (instancetype)sharedManager;

/**
 Increments the number of active network requests. If this number was zero before incrementing, this will start animating the status bar network activity indicator.
 */
- (void)incrementActivityCount;

/**
 Decrements the number of active network requests. If this number becomes zero before decrementing, this will stop animating the status bar network activity indicator.
 */
- (void)decrementActivityCount;

@end

#endif