// Copyright (c) 2012 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef BASE_MAC_BIND_OBJC_BLOCK_H_ #define BASE_MAC_BIND_OBJC_BLOCK_H_ #include <Block.h> #include "base/bind.h" #include "base/callback_forward.h" #include "base/mac/scoped_block.h" // BindBlock builds a callback from an Objective-C block. Example usages: // // Closure closure = BindBlock(^{DoSomething();}); // // Callback<int(void)> callback = BindBlock(^{return 42;}); // // Callback<void(const std::string&, const std::string&)> callback = // BindBlock(^(const std::string& arg0, const std::string& arg1) { // ... // }); namespace base { namespace internal { // Helper functions to run the block contained in the parameter. template<typename R> R RunBlock(base::mac::ScopedBlock<R(^)()> block) { R(^extracted_block)() = block.get(); return extracted_block(); } template<typename R, typename A1> R RunBlock(base::mac::ScopedBlock<R(^)(A1)> block, A1 a) { R(^extracted_block)(A1) = block.get(); return extracted_block(a); } template<typename R, typename A1, typename A2> R RunBlock(base::mac::ScopedBlock<R(^)(A1, A2)> block, A1 a, A2 b) { R(^extracted_block)(A1, A2) = block.get(); return extracted_block(a, b); } } // namespace internal // Construct a callback with no argument from an objective-C block. template<typename R> base::Callback<R(void)> BindBlock(R(^block)()) { return base::Bind(&base::internal::RunBlock<R>, base::mac::ScopedBlock<R(^)()>(Block_copy(block))); } // Construct a callback with one argument from an objective-C block. template<typename R, typename A1> base::Callback<R(A1)> BindBlock(R(^block)(A1)) { return base::Bind(&base::internal::RunBlock<R, A1>, base::mac::ScopedBlock<R(^)(A1)>(Block_copy(block))); } // Construct a callback with two arguments from an objective-C block. template<typename R, typename A1, typename A2> base::Callback<R(A1, A2)> BindBlock(R(^block)(A1, A2)) { return base::Bind(&base::internal::RunBlock<R, A1, A2>, base::mac::ScopedBlock<R(^)(A1, A2)>(Block_copy(block))); } } // namespace base #endif // BASE_MAC_BIND_OBJC_BLOCK_H_