1// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef BASE_MAC_BIND_OBJC_BLOCK_H_ 6#define BASE_MAC_BIND_OBJC_BLOCK_H_ 7 8#include <Block.h> 9 10#include "base/bind.h" 11#include "base/callback_forward.h" 12#include "base/mac/scoped_block.h" 13 14// BindBlock builds a callback from an Objective-C block. Example usages: 15// 16// Closure closure = BindBlock(^{DoSomething();}); 17// 18// Callback<int(void)> callback = BindBlock(^{return 42;}); 19// 20// Callback<void(const std::string&, const std::string&)> callback = 21// BindBlock(^(const std::string& arg0, const std::string& arg1) { 22// ... 23// }); 24 25namespace base { 26 27namespace internal { 28 29// Helper functions to run the block contained in the parameter. 30template<typename R> 31R RunBlock(base::mac::ScopedBlock<R(^)()> block) { 32 R(^extracted_block)() = block.get(); 33 return extracted_block(); 34} 35 36template<typename R, typename A1> 37R RunBlock(base::mac::ScopedBlock<R(^)(A1)> block, A1 a) { 38 R(^extracted_block)(A1) = block.get(); 39 return extracted_block(a); 40} 41 42template<typename R, typename A1, typename A2> 43R RunBlock(base::mac::ScopedBlock<R(^)(A1, A2)> block, A1 a, A2 b) { 44 R(^extracted_block)(A1, A2) = block.get(); 45 return extracted_block(a, b); 46} 47 48} // namespace internal 49 50// Construct a callback with no argument from an objective-C block. 51template<typename R> 52base::Callback<R(void)> BindBlock(R(^block)()) { 53 return base::Bind(&base::internal::RunBlock<R>, 54 base::mac::ScopedBlock<R(^)()>(Block_copy(block))); 55} 56 57// Construct a callback with one argument from an objective-C block. 58template<typename R, typename A1> 59base::Callback<R(A1)> BindBlock(R(^block)(A1)) { 60 return base::Bind(&base::internal::RunBlock<R, A1>, 61 base::mac::ScopedBlock<R(^)(A1)>(Block_copy(block))); 62} 63 64// Construct a callback with two arguments from an objective-C block. 65template<typename R, typename A1, typename A2> 66base::Callback<R(A1, A2)> BindBlock(R(^block)(A1, A2)) { 67 return base::Bind(&base::internal::RunBlock<R, A1, A2>, 68 base::mac::ScopedBlock<R(^)(A1, A2)>(Block_copy(block))); 69} 70 71} // namespace base 72 73#endif // BASE_MAC_BIND_OBJC_BLOCK_H_ 74