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 PPAPI_CPP_MOUSE_LOCK_H_ 6#define PPAPI_CPP_MOUSE_LOCK_H_ 7 8#include "ppapi/c/pp_stdint.h" 9#include "ppapi/cpp/instance_handle.h" 10 11/// @file 12/// This file defines the API for locking the target of mouse events to a 13/// specific module instance. 14 15namespace pp { 16 17class CompletionCallback; 18class Instance; 19 20/// This class allows you to associate the <code>PPP_MouseLock</code> and 21/// <code>PPB_MouseLock</code> C-based interfaces with an object. It associates 22/// itself with the given instance, and registers as the global handler for 23/// handling the <code>PPP_MouseLock</code> interface that the browser calls. 24/// 25/// You would typically use this class by inheritance on your instance or by 26/// composition. 27/// 28/// <strong>Example (inheritance):</strong> 29/// @code 30/// class MyInstance : public pp::Instance, public pp::MouseLock { 31/// class MyInstance() : pp::MouseLock(this) { 32/// } 33/// ... 34/// }; 35/// @endcode 36/// 37/// <strong>Example (composition):</strong> 38/// @code 39/// class MyMouseLock : public pp::MouseLock { 40/// ... 41/// }; 42/// 43/// class MyInstance : public pp::Instance { 44/// MyInstance() : mouse_lock_(this) { 45/// } 46/// 47/// MyMouseLock mouse_lock_; 48/// }; 49/// @endcode 50class MouseLock { 51 public: 52 /// A constructor for creating a <code>MouseLock</code>. 53 /// 54 /// @param[in] instance The instance with which this resource will be 55 /// associated. 56 explicit MouseLock(Instance* instance); 57 58 /// Destructor. 59 virtual ~MouseLock(); 60 61 /// PPP_MouseLock functions exposed as virtual functions for you to override. 62 virtual void MouseLockLost() = 0; 63 64 /// LockMouse() requests the mouse to be locked. 65 /// 66 /// While the mouse is locked, the cursor is implicitly hidden from the user. 67 /// Any movement of the mouse will generate a 68 /// <code>PP_INPUTEVENT_TYPE_MOUSEMOVE</code> event. The 69 /// <code>GetPosition()</code> function in <code>InputEvent()</code> 70 /// reports the last known mouse position just as mouse lock was 71 /// entered. The <code>GetMovement()</code> function provides relative 72 /// movement information indicating what the change in position of the mouse 73 /// would be had it not been locked. 74 /// 75 /// The browser may revoke the mouse lock for reasons including (but not 76 /// limited to) the user pressing the ESC key, the user activating another 77 /// program using a reserved keystroke (e.g. ALT+TAB), or some other system 78 /// event. 79 /// 80 /// @param[in] cc A <code>CompletionCallback</code> to be called upon 81 /// completion. 82 /// 83 /// @return An int32_t containing an error code from <code>pp_errors.h</code>. 84 int32_t LockMouse(const CompletionCallback& cc); 85 86 /// UnlockMouse causes the mouse to be unlocked, allowing it to track user 87 /// movement again. This is an asynchronous operation. The module instance 88 /// will be notified using the <code>PPP_MouseLock</code> interface when it 89 /// has lost the mouse lock. 90 void UnlockMouse(); 91 92 private: 93 InstanceHandle associated_instance_; 94}; 95 96} // namespace pp 97 98#endif // PPAPI_CPP_MOUSE_LOCK_H_ 99