event_dispatcher.cc revision 1e9bf3e0803691d0a228da41fc608347b6db4340
15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2012 The Chromium Authors. All rights reserved. 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// found in the LICENSE file. 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 5d0247b1b59f9c528cb6df88b4f2b9afaf80d181eTorne (Richard Coles)#include "ui/events/event_dispatcher.h" 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 72a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)#include <algorithm> 82a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace ui { 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 112a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)namespace { 122a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 1368043e1e95eeb07d5cae7aca370b26518b0867d6Torne (Richard Coles)class ScopedDispatchHelper : public Event::DispatcherApi { 142a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) public: 152a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) explicit ScopedDispatchHelper(Event* event) 162a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) : Event::DispatcherApi(event) { 172a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) set_result(ui::ER_UNHANDLED); 182a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 192a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 202a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) virtual ~ScopedDispatchHelper() { 212a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) set_phase(EP_POSTDISPATCH); 222a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 232a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 242a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) private: 252a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DISALLOW_COPY_AND_ASSIGN(ScopedDispatchHelper); 262a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)}; 272a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 282a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)} // namespace 292a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 302a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)EventDispatcherDelegate::EventDispatcherDelegate() 312a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) : dispatcher_(NULL) { 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 342a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)EventDispatcherDelegate::~EventDispatcherDelegate() { 352a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (dispatcher_) 362a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatcher_->OnDispatcherDelegateDestroyed(); 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 392a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)Event* EventDispatcherDelegate::current_event() { 402a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return dispatcher_ ? dispatcher_->current_event() : NULL; 412a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)} 422a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 432a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)bool EventDispatcherDelegate::DispatchEvent(EventTarget* target, Event* event) { 442a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) EventDispatcher* old_dispatcher = dispatcher_; 452a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) EventDispatcher dispatcher(this); 462a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatcher_ = &dispatcher; 472a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatcher.ProcessEvent(target, event); 482a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (!dispatcher.delegate_destroyed()) 492a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatcher_ = old_dispatcher; 502a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) else if (old_dispatcher) 512a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) old_dispatcher->OnDispatcherDelegateDestroyed(); 522a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 532a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return !dispatcher.delegate_destroyed(); 542a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)} 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 562a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)EventDispatcher::EventDispatcher(EventDispatcherDelegate* delegate) 572a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) : delegate_(delegate), 582a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) current_event_(NULL) { 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 612a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)EventDispatcher::~EventDispatcher() { 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 642a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)void EventDispatcher::OnHandlerDestroyed(EventHandler* handler) { 652a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) handler_list_.erase(std::find(handler_list_.begin(), 662a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) handler_list_.end(), 672a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) handler)); 685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 702a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)void EventDispatcher::ProcessEvent(EventTarget* target, Event* event) { 712a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (!target || !target->CanAcceptEvent(*event)) 722a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return; 732a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 742a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) ScopedDispatchHelper dispatch_helper(event); 752a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatch_helper.set_target(target); 762a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 772a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) handler_list_.clear(); 782a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) target->GetPreTargetHandlers(&handler_list_); 792a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 802a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatch_helper.set_phase(EP_PRETARGET); 811e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) DispatchEventToEventHandlers(&handler_list_, event); 822a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (event->handled()) 832a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return; 842a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 852a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // If the event hasn't been consumed, trigger the default handler. Note that 862a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // even if the event has already been handled (i.e. return result has 872a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // ER_HANDLED set), that means that the event should still be processed at 882a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // this layer, however it should not be processed in the next layer of 892a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // abstraction. 902a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (delegate_ && delegate_->CanDispatchToTarget(target)) { 912a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatch_helper.set_phase(EP_TARGET); 922a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DispatchEvent(target, event); 932a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (event->handled()) 942a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return; 952a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 962a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 972a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (!delegate_ || !delegate_->CanDispatchToTarget(target)) 982a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return; 992a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 1002a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) handler_list_.clear(); 1012a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) target->GetPostTargetHandlers(&handler_list_); 1022a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) dispatch_helper.set_phase(EP_POSTTARGET); 1031e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) DispatchEventToEventHandlers(&handler_list_, event); 1045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1062a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)void EventDispatcher::OnDispatcherDelegateDestroyed() { 1072a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) delegate_ = NULL; 1085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)//////////////////////////////////////////////////////////////////////////////// 1112a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)// EventDispatcher, private: 1122a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 1131e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles)void EventDispatcher::DispatchEventToEventHandlers(EventHandlerList* list, 1142a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) Event* event) { 1151e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) for (EventHandlerList::const_iterator it = list->begin(), 1161e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) end = list->end(); it != end; ++it) { 1172a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) (*it)->dispatchers_.push(this); 1182a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 1192a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 1201e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) while (!list->empty()) { 1211e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) EventHandler* handler = (*list->begin()); 1222a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (delegate_ && !event->stopped_propagation()) 1232a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DispatchEvent(handler, event); 1242a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 1251e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) if (!list->empty() && *list->begin() == handler) { 1262a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // The handler has not been destroyed (because if it were, then it would 1272a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // have been removed from the list). 1282a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) CHECK(handler->dispatchers_.top() == this); 1292a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) handler->dispatchers_.pop(); 1301e9bf3e0803691d0a228da41fc608347b6db4340Torne (Richard Coles) list->erase(list->begin()); 1312a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 1322a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 1332a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)} 1342a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 1352a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)void EventDispatcher::DispatchEvent(EventHandler* handler, Event* event) { 1362a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // If the target has been invalidated or deleted, don't dispatch the event. 1372a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (!delegate_->CanDispatchToTarget(event->target())) { 138c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) if (event->cancelable()) 139c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) event->StopPropagation(); 1402a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return; 1412a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 1425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1432a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) base::AutoReset<Event*> event_reset(¤t_event_, event); 1442a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) handler->OnEvent(event); 145c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) if (!delegate_ && event->cancelable()) 146c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) event->StopPropagation(); 1475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace ui 150