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 15 namespace pp { 16 17 class CompletionCallback; 18 class 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 50 class 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
