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 UI_BASE_TOUCH_TOUCH_DEVICE_H_ 6 #define UI_BASE_TOUCH_TOUCH_DEVICE_H_ 7 8 #include "ui/base/ui_export.h" 9 10 namespace ui { 11 12 // TODO(sblom): This is non-standard, and should be removed before 13 // RuntimeEnabledFlags::PointerEventsMaxTouchPoints is marked stable. 14 // Tracked by: http://crbug.com/308649 15 const int kMaxTouchPointsUnknown = -1; 16 17 // Returns true if a touch device is available. 18 UI_EXPORT bool IsTouchDevicePresent(); 19 20 // Returns the maximum number of simultaneous touch contacts supported 21 // by the device. In the case of devices with multiple digitizers (e.g. 22 // multiple touchscreens), the value MUST be the maximum of the set of 23 // maximum supported contacts by each individual digitizer. 24 // For example, suppose a device has 3 touchscreens, which support 2, 5, 25 // and 10 simultaneous touch contacts, respectively. This returns 10. 26 // http://www.w3.org/TR/pointerevents/#widl-Navigator-maxTouchPoints 27 UI_EXPORT int MaxTouchPoints(); 28 29 } // namespace ui 30 31 #endif // UI_BASE_TOUCH_TOUCH_DEVICE_H_ 32