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/*
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Licensed to the Software Freedom Conservancy (SFC) under one
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or more contributor license agreements. See the NOTICE file
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distributed with this work for additional information
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regarding copyright ownership. The SFC licenses this file
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to you under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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     http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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#ifndef event_firing_thread_h_
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#define event_firing_thread_h_
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/**
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 * The purpose of background, persistent event firing is to make mouse hovering
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 * on Windows work. IE, specifically, would consider the mouse to have moved
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 * outside the window if WM_MOUSEMOVE messages are not constantly sent to
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 * the window.
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 *
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 * This is achieved by starting a background thread that keeps firing those
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 * messages every 10 ms. Event firing is paused when other mouse actions occur.
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 * Additionally, the state of the input devices must be updated so that
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 * WM_MOUSEMOVE events sent are consistent with previous actions. This
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 * boils down to whether the Shift key is pressed and whether the left
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 * mouse button is pressed (for drag-and-drop to work).
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 **/
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// Start or resume persistent "mouse over" event firing by a
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// background thread.
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extern void resumePersistentEventsFiring(
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    HWND inputTo, long toX, long toY, WPARAM buttonValue);
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// Resume without changing the target. Used after pausing evennt
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// firing for mouse actions.
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extern void resumePersistentEventsFiring();
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// Pauses persistent event firing by the background thread.
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extern void pausePersistentEventsFiring();
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// When the state of the shift key changes, update the background thread
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// so that subsequent mouse over events will have the right keyboard state.
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extern void updateShiftKeyState(bool isShiftPressed);
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// When the left mouse button is pressed, update the background thread.
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// Otherwise IE gets confused.
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extern void updateLeftMouseButtonState(bool isButtonPressed);
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#endif  // event_firing_thread_h_
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