ipc/chromium/src/base/singleton_objc.h@6474c204b198 (annotated)
ipc/chromium/src/base/singleton_objc.h
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | // Copyright (c) 2008 The Chromium Authors. All rights reserved. |
| michael@0 | 2 | // Use of this source code is governed by a BSD-style license that can be |
| michael@0 | 3 | // found in the LICENSE file. |
| michael@0 | 4 | |
| michael@0 | 5 | // Support for using the Singleton<T> pattern with Objective-C objects. A |
| michael@0 | 6 | // SingletonObjC is the same as a Singleton, except the default traits are |
| michael@0 | 7 | // appropriate for Objective-C objects. A typical Objective-C object of type |
| michael@0 | 8 | // NSExampleType can be maintained as a singleton and accessed with: |
| michael@0 | 9 | // |
| michael@0 | 10 | // NSExampleType* exampleSingleton = SingletonObjC<NSExampleType>::get(); |
| michael@0 | 11 | // |
| michael@0 | 12 | // The first time this is used, it will create exampleSingleton as the result |
| michael@0 | 13 | // of [[NSExampleType alloc] init]. Subsequent calls will return the same |
| michael@0 | 14 | // NSExampleType* object. The object will be released by calling |
| michael@0 | 15 | // -[NSExampleType release] when Singleton's atexit routines run |
| michael@0 | 16 | // (see singleton.h). |
| michael@0 | 17 | // |
| michael@0 | 18 | // For Objective-C objects initialized through means other than the |
| michael@0 | 19 | // no-parameter -init selector, DefaultSingletonObjCTraits may be extended |
| michael@0 | 20 | // as needed: |
| michael@0 | 21 | // |
| michael@0 | 22 | // struct FooSingletonTraits : public DefaultSingletonObjCTraits<Foo> { |
| michael@0 | 23 | // static Foo* New() { |
| michael@0 | 24 | // return [[Foo alloc] initWithName:@"selecty"]; |
| michael@0 | 25 | // } |
| michael@0 | 26 | // } |
| michael@0 | 27 | // ... |
| michael@0 | 28 | // Foo* widgetSingleton = SingletonObjC<Foo, FooSingletonTraits>::get(); |
| michael@0 | 29 | |
| michael@0 | 30 | #ifndef BASE_SINGLETON_OBJC_H_ |
| michael@0 | 31 | #define BASE_SINGLETON_OBJC_H_ |
| michael@0 | 32 | |
| michael@0 | 33 | #import <Foundation/Foundation.h> |
| michael@0 | 34 | #include "base/singleton.h" |
| michael@0 | 35 | |
| michael@0 | 36 | // Singleton traits usable to manage traditional Objective-C objects, which |
| michael@0 | 37 | // are instantiated by sending |alloc| and |init| messages, and are deallocated |
| michael@0 | 38 | // in a memory-managed environment when their retain counts drop to 0 by |
| michael@0 | 39 | // sending |release| messages. |
| michael@0 | 40 | template<typename Type> |
| michael@0 | 41 | struct DefaultSingletonObjCTraits : public DefaultSingletonTraits<Type> { |
| michael@0 | 42 | static Type* New() { |
| michael@0 | 43 | return [[Type alloc] init]; |
| michael@0 | 44 | } |
| michael@0 | 45 | |
| michael@0 | 46 | static void Delete(Type* object) { |
| michael@0 | 47 | [object release]; |
| michael@0 | 48 | } |
| michael@0 | 49 | }; |
| michael@0 | 50 | |
| michael@0 | 51 | // Exactly like Singleton, but without the DefaultSingletonObjCTraits as the |
| michael@0 | 52 | // default trait class. This makes it straightforward for Objective-C++ code |
| michael@0 | 53 | // to hold Objective-C objects as singletons. |
| michael@0 | 54 | template<typename Type, |
| michael@0 | 55 | typename Traits = DefaultSingletonObjCTraits<Type>, |
| michael@0 | 56 | typename DifferentiatingType = Type> |
| michael@0 | 57 | class SingletonObjC : public Singleton<Type, Traits, DifferentiatingType> { |
| michael@0 | 58 | }; |
| michael@0 | 59 | |
| michael@0 | 60 | #endif // BASE_SINGLETON_OBJC_H_ |
