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content / browser / android / overscroll_controller_android.cc [blame]
// 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/android/overscroll_controller_android.h"
#include "base/command_line.h"
#include "base/metrics/field_trial_params.h"
#include "cc/layers/layer.h"
#include "components/viz/common/quads/compositor_frame_metadata.h"
#include "content/public/browser/navigation_controller.h"
#include "content/public/common/content_features.h"
#include "content/public/common/content_switches.h"
#include "third_party/blink/public/common/input/web_gesture_event.h"
#include "third_party/blink/public/common/input/web_input_event.h"
#include "ui/android/edge_effect.h"
#include "ui/android/resources/resource_manager.h"
#include "ui/android/window_android.h"
#include "ui/android/window_android_compositor.h"
#include "ui/base/l10n/l10n_util_android.h"
#include "ui/base/ui_base_switches.h"
#include "ui/base/ui_base_switches_util.h"
#include "ui/events/blink/did_overscroll_params.h"
using ui::DidOverscrollParams;
using ui::EdgeEffect;
using ui::OverscrollGlow;
using ui::OverscrollGlowClient;
using ui::OverscrollRefresh;
namespace content {
namespace {
// If the glow effect alpha is greater than this value, the refresh effect will
// be suppressed. This value was experimentally determined to provide a
// reasonable balance between avoiding accidental refresh activation and
// minimizing the wait required to refresh after the glow has been triggered.
const float kMinGlowAlphaToDisableRefresh = 0.085f;
std::unique_ptr<EdgeEffect> CreateGlowEdgeEffect(
ui::ResourceManager* resource_manager,
float dpi_scale) {
DCHECK(resource_manager);
return std::make_unique<EdgeEffect>(resource_manager);
}
std::unique_ptr<OverscrollGlow> CreateGlowEffect(OverscrollGlowClient* client) {
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kDisableOverscrollEdgeEffect)) {
return nullptr;
}
// The elastic overscroll feature indicates when the user is scrolling beyond
// the range of the scrollable area. Showing a glow in addition would be
// redundant.
if (switches::IsElasticOverscrollEnabled())
return nullptr;
return std::make_unique<OverscrollGlow>(client);
}
std::unique_ptr<OverscrollRefresh> CreateRefreshEffect(
ui::OverscrollRefreshHandler* overscroll_refresh_handler,
float dpi_scale) {
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kDisablePullToRefreshEffect)) {
return nullptr;
}
float edge_width = OverscrollRefresh::kDefaultNavigationEdgeWidth * dpi_scale;
return std::make_unique<OverscrollRefresh>(overscroll_refresh_handler,
edge_width);
}
} // namespace
// static
std::unique_ptr<OverscrollControllerAndroid>
OverscrollControllerAndroid::CreateForTests(
ui::WindowAndroidCompositor* compositor,
float dpi_scale,
std::unique_ptr<ui::OverscrollGlow> glow_effect,
std::unique_ptr<ui::OverscrollRefresh> refresh_effect) {
return std::unique_ptr<OverscrollControllerAndroid>(
new OverscrollControllerAndroid(compositor, dpi_scale,
std::move(glow_effect),
std::move(refresh_effect)));
}
OverscrollControllerAndroid::OverscrollControllerAndroid(
ui::WindowAndroidCompositor* compositor,
float dpi_scale,
std::unique_ptr<ui::OverscrollGlow> glow_effect,
std::unique_ptr<ui::OverscrollRefresh> refresh_effect)
: compositor_(compositor),
dpi_scale_(dpi_scale),
enabled_(true),
glow_effect_(std::move(glow_effect)),
refresh_effect_(std::move(refresh_effect)) {}
OverscrollControllerAndroid::OverscrollControllerAndroid(
ui::OverscrollRefreshHandler* overscroll_refresh_handler,
ui::WindowAndroidCompositor* compositor,
float dpi_scale)
: compositor_(compositor),
dpi_scale_(dpi_scale),
enabled_(true),
glow_effect_(CreateGlowEffect(this)),
refresh_effect_(
CreateRefreshEffect(overscroll_refresh_handler, dpi_scale_)) {
DCHECK(compositor_);
}
OverscrollControllerAndroid::~OverscrollControllerAndroid() {
}
bool OverscrollControllerAndroid::WillHandleGestureEvent(
const blink::WebGestureEvent& event) {
if (!enabled_)
return false;
if (!refresh_effect_)
return false;
// Suppress refresh detection if the glow effect is still prominent.
if (glow_effect_ && glow_effect_->IsActive()) {
if (glow_effect_->GetVisibleAlpha() > kMinGlowAlphaToDisableRefresh)
return false;
}
bool handled = false;
switch (event.GetType()) {
case blink::WebInputEvent::Type::kGestureScrollBegin:
refresh_effect_->OnScrollBegin(
gfx::ScalePoint(event.PositionInWidget(), dpi_scale_));
break;
case blink::WebInputEvent::Type::kGestureScrollUpdate: {
gfx::Vector2dF scroll_delta(event.data.scroll_update.delta_x,
event.data.scroll_update.delta_y);
scroll_delta.Scale(dpi_scale_);
handled = refresh_effect_->WillHandleScrollUpdate(scroll_delta);
} break;
case blink::WebInputEvent::Type::kGestureScrollEnd:
refresh_effect_->OnScrollEnd(gfx::Vector2dF());
break;
case blink::WebInputEvent::Type::kGestureFlingStart: {
if (refresh_effect_->IsActive()) {
gfx::Vector2dF scroll_velocity(event.data.fling_start.velocity_x,
event.data.fling_start.velocity_y);
scroll_velocity.Scale(dpi_scale_);
refresh_effect_->OnScrollEnd(scroll_velocity);
// TODO(jdduke): Figure out a cleaner way of suppressing a fling.
// It's important that the any downstream code sees a scroll-ending
// event (in this case GestureFlingStart) if it has seen a scroll begin.
// Thus, we cannot simply consume the fling. Changing the event type to
// a GestureScrollEnd might work in practice, but could lead to
// unexpected results. For now, simply truncate the fling velocity, but
// not to zero as downstream code may not expect a zero-velocity fling.
blink::WebGestureEvent& modified_event =
const_cast<blink::WebGestureEvent&>(event);
modified_event.data.fling_start.velocity_x = .01f;
modified_event.data.fling_start.velocity_y = .01f;
}
} break;
case blink::WebInputEvent::Type::kGesturePinchBegin:
refresh_effect_->ReleaseWithoutActivation();
break;
default:
break;
}
return handled;
}
void OverscrollControllerAndroid::OnGestureEventAck(
const blink::WebGestureEvent& event,
blink::mojom::InputEventResultState ack_result) {
if (!enabled_)
return;
// The overscroll effect requires an explicit release signal that may not be
// sent from the renderer compositor.
if (event.GetType() == blink::WebInputEvent::Type::kGestureScrollEnd ||
event.GetType() == blink::WebInputEvent::Type::kGestureFlingStart) {
OnOverscrolled(DidOverscrollParams());
}
if (event.GetType() == blink::WebInputEvent::Type::kGestureScrollUpdate &&
refresh_effect_) {
// The effect should only be allowed if the scroll events go unconsumed.
if (refresh_effect_->IsAwaitingScrollUpdateAck() &&
ack_result == blink::mojom::InputEventResultState::kConsumed) {
refresh_effect_->Reset();
}
}
}
void OverscrollControllerAndroid::OnOverscrolled(
const DidOverscrollParams& params) {
if (!enabled_)
return;
if (refresh_effect_) {
refresh_effect_->OnOverscrolled(params.overscroll_behavior);
if (refresh_effect_->IsActive() ||
refresh_effect_->IsAwaitingScrollUpdateAck()) {
// An active (or potentially active) refresh effect should always pre-empt
// the passive glow effect.
return;
}
}
// When use-zoom-for-dsf is enabled, each value of params was already scaled
// by the device scale factor.
gfx::Vector2dF accumulated_overscroll = params.accumulated_overscroll;
gfx::Vector2dF latest_overscroll_delta = params.latest_overscroll_delta;
gfx::Vector2dF current_fling_velocity = params.current_fling_velocity;
gfx::Vector2dF overscroll_location =
params.causal_event_viewport_point.OffsetFromOrigin();
if (params.overscroll_behavior.x == cc::OverscrollBehavior::Type::kNone) {
accumulated_overscroll.set_x(0);
latest_overscroll_delta.set_x(0);
current_fling_velocity.set_x(0);
}
if (params.overscroll_behavior.y == cc::OverscrollBehavior::Type::kNone) {
accumulated_overscroll.set_y(0);
latest_overscroll_delta.set_y(0);
current_fling_velocity.set_y(0);
}
if (glow_effect_ && glow_effect_->OnOverscrolled(
base::TimeTicks::Now(), accumulated_overscroll,
latest_overscroll_delta, current_fling_velocity,
overscroll_location)) {
SetNeedsAnimate();
}
}
bool OverscrollControllerAndroid::Animate(base::TimeTicks current_time,
cc::slim::Layer* parent_layer) {
DCHECK(parent_layer);
if (!enabled_ || !glow_effect_)
return false;
return glow_effect_->Animate(current_time, parent_layer);
}
void OverscrollControllerAndroid::OnFrameMetadataUpdated(
float page_scale_factor,
float device_scale_factor,
const gfx::SizeF& scrollable_viewport_size,
const gfx::SizeF& root_layer_size,
const gfx::PointF& root_scroll_offset,
bool root_overflow_y_hidden) {
if (!refresh_effect_ && !glow_effect_)
return;
// When use-zoom-for-dsf is enabled, frame_metadata.page_scale_factor was
// already scaled by the device scale factor.
float scale_factor = page_scale_factor;
gfx::SizeF viewport_size =
gfx::ScaleSize(scrollable_viewport_size, scale_factor);
gfx::SizeF content_size = gfx::ScaleSize(root_layer_size, scale_factor);
gfx::PointF content_scroll_offset =
gfx::ScalePoint(root_scroll_offset, scale_factor);
if (refresh_effect_) {
refresh_effect_->OnFrameUpdated(viewport_size, content_scroll_offset,
content_size, root_overflow_y_hidden);
}
if (glow_effect_) {
glow_effect_->OnFrameUpdated(viewport_size, content_size,
content_scroll_offset);
}
}
void OverscrollControllerAndroid::Enable() {
enabled_ = true;
}
void OverscrollControllerAndroid::Disable() {
if (!enabled_)
return;
enabled_ = false;
if (!enabled_) {
if (refresh_effect_)
refresh_effect_->Reset();
if (glow_effect_)
glow_effect_->Reset();
}
}
std::unique_ptr<EdgeEffect> OverscrollControllerAndroid::CreateEdgeEffect() {
return CreateGlowEdgeEffect(&compositor_->GetResourceManager(), dpi_scale_);
}
void OverscrollControllerAndroid::SetNeedsAnimate() {
compositor_->SetNeedsAnimate();
}
} // namespace content