| // Copyright 2014 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 THIRD_PARTY_BLINK_RENDERER_CORE_FRAME_PLATFORM_EVENT_CONTROLLER_H_ |
| #define THIRD_PARTY_BLINK_RENDERER_CORE_FRAME_PLATFORM_EVENT_CONTROLLER_H_ |
| |
| #include "third_party/blink/public/platform/task_type.h" |
| #include "third_party/blink/renderer/core/core_export.h" |
| #include "third_party/blink/renderer/core/page/page_visibility_observer.h" |
| #include "third_party/blink/renderer/platform/heap/handle.h" |
| #include "third_party/blink/renderer/platform/scheduler/public/post_cancellable_task.h" |
| #include "third_party/blink/renderer/platform/timer.h" |
| |
| namespace blink { |
| |
| // Base controller class for registering controllers with a dispatcher. |
| // It watches page visibility and calls stopUpdating when page is not visible. |
| // It provides a DidUpdateData() callback method which is called when new data |
| // it available. |
| class CORE_EXPORT PlatformEventController : public PageVisibilityObserver { |
| public: |
| void StartUpdating(); |
| void StopUpdating(); |
| |
| // This is called when new data becomes available. |
| virtual void DidUpdateData() = 0; |
| |
| void Trace(blink::Visitor*) override; |
| Document* GetDocument() const { return document_; } |
| |
| protected: |
| explicit PlatformEventController(Document*); |
| virtual ~PlatformEventController(); |
| |
| virtual void RegisterWithDispatcher() = 0; |
| virtual void UnregisterWithDispatcher() = 0; |
| |
| // When true initiates a one-shot DidUpdateData() when StartUpdating() is |
| // called. |
| virtual bool HasLastData() = 0; |
| |
| bool has_event_listener_; |
| |
| private: |
| // Inherited from PageVisibilityObserver. |
| void PageVisibilityChanged() override; |
| |
| void UpdateCallback(); |
| |
| bool is_active_; |
| Member<Document> document_; |
| TaskHandle update_callback_handle_; |
| }; |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_RENDERER_CORE_FRAME_PLATFORM_EVENT_CONTROLLER_H_ |