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// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/renderer_host/input/stylus_text_selector.h"
#include "base/check_op.h"
#include "base/notreached.h"
#include "ui/events/event_constants.h"
#include "ui/events/gesture_detection/gesture_detector.h"
#include "ui/events/gesture_detection/gesture_provider_config_helper.h"
#include "ui/events/velocity_tracker/motion_event.h"
using ui::GestureDetector;
using ui::MotionEvent;
namespace content {
namespace {
std::unique_ptr<GestureDetector> CreateGestureDetector(
ui::GestureListener* listener) {
GestureDetector::Config config =
ui::GetGestureProviderConfig(
ui::GestureProviderConfigType::CURRENT_PLATFORM)
.gesture_detector_config;
ui::DoubleTapListener* null_double_tap_listener = nullptr;
// Doubletap, showpress and longpress detection are not required, and
// should be explicitly disabled for efficiency.
std::unique_ptr<ui::GestureDetector> detector(
new ui::GestureDetector(config, listener, null_double_tap_listener));
detector->set_press_and_hold_enabled(false);
detector->set_showpress_enabled(false);
return detector;
}
} // namespace
StylusTextSelector::StylusTextSelector(StylusTextSelectorClient* client)
: client_(client),
text_selection_triggered_(false),
secondary_button_pressed_(false),
drag_state_(NO_DRAG),
anchor_x_(0.0f),
anchor_y_(0.0f) {
DCHECK(client);
}
StylusTextSelector::~StylusTextSelector() {
}
bool StylusTextSelector::OnTouchEvent(const MotionEvent& event) {
// Only trigger selection on ACTION_DOWN to prevent partial touch or gesture
// sequences from being forwarded.
if (event.GetAction() == MotionEvent::Action::DOWN)
text_selection_triggered_ = ShouldStartTextSelection(event);
if (!text_selection_triggered_)
return false;
// For Android version < M, stylus button pressed state is BUTTON_SECONDARY.
// From Android M, this state has changed to BUTTON_STYLUS_PRIMARY.
secondary_button_pressed_ =
event.GetButtonState() == MotionEvent::BUTTON_SECONDARY ||
event.GetButtonState() == MotionEvent::BUTTON_STYLUS_PRIMARY;
switch (event.GetAction()) {
case MotionEvent::Action::DOWN:
drag_state_ = NO_DRAG;
anchor_x_ = event.GetX();
anchor_y_ = event.GetY();
break;
case MotionEvent::Action::MOVE:
if (!secondary_button_pressed_) {
if (drag_state_ == DRAGGING_WITH_BUTTON_PRESSED)
drag_state_ = DRAGGING_WITH_BUTTON_RELEASED;
anchor_x_ = event.GetX();
anchor_y_ = event.GetY();
}
break;
case MotionEvent::Action::UP:
case MotionEvent::Action::CANCEL:
if (drag_state_ == DRAGGING_WITH_BUTTON_PRESSED ||
drag_state_ == DRAGGING_WITH_BUTTON_RELEASED)
client_->OnStylusSelectEnd(event.GetX(), event.GetY());
drag_state_ = NO_DRAG;
break;
case MotionEvent::Action::POINTER_UP:
case MotionEvent::Action::POINTER_DOWN:
break;
case MotionEvent::Action::NONE:
case MotionEvent::Action::HOVER_ENTER:
case MotionEvent::Action::HOVER_EXIT:
case MotionEvent::Action::HOVER_MOVE:
case MotionEvent::Action::BUTTON_PRESS:
case MotionEvent::Action::BUTTON_RELEASE:
NOTREACHED();
}
if (!gesture_detector_)
gesture_detector_ = CreateGestureDetector(this);
gesture_detector_->OnTouchEvent(event, false /* should_process_double_tap */);
// Always return true, even if |gesture_detector_| technically doesn't
// consume the event. This prevents forwarding of a partial touch stream.
return true;
}
bool StylusTextSelector::OnSingleTapUp(const MotionEvent& e, int tap_count) {
DCHECK(text_selection_triggered_);
DCHECK_NE(DRAGGING_WITH_BUTTON_PRESSED, drag_state_);
client_->OnStylusSelectTap(e.GetEventTime(), e.GetX(), e.GetY());
return true;
}
bool StylusTextSelector::OnScroll(const MotionEvent& e1,
const MotionEvent& e2,
const MotionEvent& secondary_pointer_down,
float distance_x,
float distance_y) {
DCHECK(text_selection_triggered_);
// Return if Stylus button is not pressed.
if (!secondary_button_pressed_)
return true;
if (drag_state_ == NO_DRAG || drag_state_ == DRAGGING_WITH_BUTTON_RELEASED) {
drag_state_ = DRAGGING_WITH_BUTTON_PRESSED;
client_->OnStylusSelectBegin(anchor_x_, anchor_y_, e2.GetX(), e2.GetY());
} else {
client_->OnStylusSelectUpdate(e2.GetX(), e2.GetY());
}
return true;
}
// static
bool StylusTextSelector::ShouldStartTextSelection(const MotionEvent& event) {
DCHECK_GT(event.GetPointerCount(), 0u);
// Currently we are supporting stylus-only cases.
const bool is_stylus = event.GetToolType(0) == MotionEvent::ToolType::STYLUS;
// For Android version < M, stylus button pressed state is BUTTON_SECONDARY.
// From Android M, this state has changed to BUTTON_STYLUS_PRIMARY.
const bool is_only_secondary_button_pressed =
event.GetButtonState() == MotionEvent::BUTTON_SECONDARY ||
event.GetButtonState() == MotionEvent::BUTTON_STYLUS_PRIMARY;
return is_stylus && is_only_secondary_button_pressed;
}
} // namespace content
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