blob: 1cb49084c18880a43ff2fb23e00a4c7b47eb0f31 [file] [log] [blame]
// Copyright (c) 2012 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.
#include "ui/base/touch/touch_device.h"
#include "base/logging.h"
#include "base/win/win_util.h"
#include "ui/base/win/hidden_window.h"
namespace ui {
namespace {
bool IsTouchDevicePresent() {
int value = GetSystemMetrics(SM_DIGITIZER);
return (value & NID_READY) &&
((value & NID_INTEGRATED_TOUCH) || (value & NID_EXTERNAL_TOUCH));
}
} // namespace
// The following method logic is as follow :
// - On versions prior to Windows 8 it will always return POINTER_TYPE_FINE
// and/or POINTER_TYPE_COARSE (if the device has a touch screen).
// - If the device is a detachable/convertible win8/10 device and the keyboard/
// trackpad is detached/flipped it will always return POINTER_TYPE_COARSE.
// It does not cover the case where an external mouse/keyboard is connected
// while the device is used as a tablet. This is because Windows doesn't provide
// us a reliable way to detect keyboard/mouse presence with
// GetSystemMetrics(SM_MOUSEPRESENT).
// - If the device doesn't have a touch screen it will return POINTER_TYPE_FINE.
// In the rare cases (this is Microsoft documentation) where
// GetSystemMetrics(SM_MOUSEPRESENT) returns 0 we will return POINTER_TYPE_NONE.
// - If the device has a touch screen the available pointer devices are
// POINTER_TYPE_FINE and POINTER_TYPE_COARSE.
int GetAvailablePointerTypes() {
// IsTabletDevice guarantees us that :
// - The device has a touch screen.
// - It is used as a tablet which means that it has no keyboard connected.
// On Windows 10 it means that it is verifying with ConvertibleSlateMode.
if (base::win::IsDeviceUsedAsATablet(nullptr))
return POINTER_TYPE_COARSE;
bool is_touch_device_present = IsTouchDevicePresent();
if (GetSystemMetrics(SM_MOUSEPRESENT) == 0 && !is_touch_device_present)
return POINTER_TYPE_NONE;
int available_pointer_types = POINTER_TYPE_FINE;
if (is_touch_device_present)
available_pointer_types |= POINTER_TYPE_COARSE;
return available_pointer_types;
}
// This method follows the same logic as above but with hover types.
int GetAvailableHoverTypes() {
if (base::win::IsDeviceUsedAsATablet(nullptr))
return HOVER_TYPE_NONE;
if (GetSystemMetrics(SM_MOUSEPRESENT) != 0)
return HOVER_TYPE_HOVER;
return HOVER_TYPE_NONE;
}
TouchScreensAvailability GetTouchScreensAvailability() {
if (!IsTouchDevicePresent())
return TouchScreensAvailability::NONE;
return TouchScreensAvailability::ENABLED;
}
int MaxTouchPoints() {
if (!IsTouchDevicePresent())
return 0;
return GetSystemMetrics(SM_MAXIMUMTOUCHES);
}
PointerType GetPrimaryPointerType(int available_pointer_types) {
if (available_pointer_types & POINTER_TYPE_FINE)
return POINTER_TYPE_FINE;
if (available_pointer_types & POINTER_TYPE_COARSE)
return POINTER_TYPE_COARSE;
DCHECK_EQ(available_pointer_types, POINTER_TYPE_NONE);
return POINTER_TYPE_NONE;
}
HoverType GetPrimaryHoverType(int available_hover_types) {
if (available_hover_types & HOVER_TYPE_HOVER)
return HOVER_TYPE_HOVER;
DCHECK_EQ(available_hover_types, HOVER_TYPE_NONE);
return HOVER_TYPE_NONE;
}
} // namespace ui