[Android] Composited selection handle rendering

content/browser/renderer_host/input/touch_selection_controller.cc

+// Copyright 2014 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 "content/browser/renderer_host/input/touch_selection_controller.h"
+
+#include "base/logging.h"
+#include "third_party/WebKit/public/web/WebInputEvent.h"
+
+namespace content {
+
+TouchSelectionController::TouchSelectionController(
+    TouchSelectionControllerClient* client)
+    : client_(client),
+      start_orientation_(TOUCH_HANDLE_ORIENTATION_UNDEFINED),
+      start_visible_(false),
+      end_orientation_(TOUCH_HANDLE_ORIENTATION_UNDEFINED),
+      end_visible_(false),
+      is_insertion_active_(false),
+      allow_automatic_insertion_activation_(false),
+      is_selection_active_(false),
+      allow_automatic_selection_activation_(false),
+      selection_editable_(false),
+      selection_editable_for_last_update_(false) {
+  DCHECK(client_);
+  HideAndDisallowAutomaticShowing();
+}
+
+TouchSelectionController::~TouchSelectionController() {
+}
+
+void TouchSelectionController::OnSelectionBoundsChanged(
+    const gfx::RectF& start_rect,
+    TouchHandleOrientation start_orientation,
+    bool start_visible,
+    const gfx::RectF& end_rect,
+    TouchHandleOrientation end_orientation,
+    bool end_visible) {
+  if (!allow_automatic_selection_activation_ &&
+      !allow_automatic_insertion_activation_)
+    return;
+
+  if (start_rect_ == start_rect && end_rect_ == end_rect &&
+      start_orientation_ == start_orientation &&
+      end_orientation_ == end_orientation &&
+      start_visible_ == start_visible && end_visible_ == end_visible &&
+      selection_editable_ == selection_editable_for_last_update_)
+    return;
+
+  start_rect_ = start_rect;
+  start_orientation_ = start_orientation;
+  start_visible_ = start_visible;
+  end_rect_ = end_rect;
+  end_orientation_ = end_orientation;
+  end_visible_ = end_visible;
+  selection_editable_for_last_update_ = selection_editable_;
+
+  const bool is_selection_dragging =
+      is_selection_active_ && (start_selection_handle_->is_dragging() ||
+                               end_selection_handle_->is_dragging());
+
+  // It's possible that the bounds temporarily overlap while a selection handle
+  // is being dragged, incorrectly reporting a CENTER orientation.
+  // TODO(jdduke): This safeguard is racy, as it's possible the delayed response
+  // from handle positioning occurs *after* the handle dragging has ceased.
+  // Instead, prevent selection -> insertion transitions without an intervening
+  // action or selection clearing of some sort, crbug.com/392696.
+  if (is_selection_dragging) {
+    if (start_orientation_ == TOUCH_HANDLE_CENTER)
+      start_orientation_ = start_selection_handle_->orientation();
+    if (end_orientation_ == TOUCH_HANDLE_CENTER)
+      end_orientation_ = end_selection_handle_->orientation();
+  }
+
+  const gfx::PointF start = GetStartPosition();
+  const gfx::PointF end = GetEndPosition();
+  if (start != end ||
+      (is_selection_dragging &&
+       start_orientation_ != TOUCH_HANDLE_ORIENTATION_UNDEFINED &&
+       end_orientation_ != TOUCH_HANDLE_ORIENTATION_UNDEFINED)) {
+    OnSelectionChanged();
+    return;
+  }
+
+  if (start_orientation_ == TOUCH_HANDLE_CENTER) {
+    OnInsertionChanged();
+    return;
+  }
+
+  HideAndDisallowAutomaticShowing();
+}
+
+bool TouchSelectionController::WillHandleTouchEvent(
+    const ui::MotionEvent& event) {
+  if (is_insertion_active_) {
+    DCHECK(insertion_handle_);
+    return insertion_handle_->WillHandleTouchEvent(event);
+  }
+
+  if (is_selection_active_) {
+    DCHECK(start_selection_handle_);
+    DCHECK(end_selection_handle_);
+    return start_selection_handle_->WillHandleTouchEvent(event) ||
+           end_selection_handle_->WillHandleTouchEvent(event);
+  }
+
+  return false;
+}
+
+void TouchSelectionController::AllowAutomaticInsertionShowing() {
+  if (allow_automatic_insertion_activation_)
+    return;
+  allow_automatic_insertion_activation_ = true;
+  if (!is_insertion_active_ && !is_selection_active_)
+    ResetCachedValues();
+}
+
+void TouchSelectionController::AllowAutomaticSelectionShowing() {
+  if (allow_automatic_selection_activation_)
+    return;
+  allow_automatic_selection_activation_ = true;
+  if (!is_insertion_active_ && !is_selection_active_)
+    ResetCachedValues();
+}
+
+void TouchSelectionController::HideAndDisallowAutomaticShowing() {
+  DeactivateInsertion();
+  DeactivateSelection();
+  allow_automatic_insertion_activation_ = false;
+  allow_automatic_selection_activation_ = false;
+}
+
+void TouchSelectionController::OnSelectionEditable(bool editable) {
+  if (selection_editable_ == editable)
+    return;
+  selection_editable_ = editable;
+  if (!selection_editable_)
+    DeactivateInsertion();
+}
+
+bool TouchSelectionController::Animate(base::TimeTicks frame_time) {
+  if (is_insertion_active_)
+    return insertion_handle_->Animate(frame_time);
+
+  if (is_selection_active_) {
+    bool needs_animate = start_selection_handle_->Animate(frame_time);
+    needs_animate |= end_selection_handle_->Animate(frame_time);
+    return needs_animate;
+  }
+
+  return false;
+}
+
+void TouchSelectionController::OnHandleDragBegin(const TouchHandle& handle) {
+  if (&handle == insertion_handle_.get())
+    return;
+
+  if (&handle == start_selection_handle_.get()) {
+    fixed_handle_position_ = end_selection_handle_->position() -
+                             gfx::Vector2dF(0, GetEndLineHeight() / 2.f);
+  } else {
+    fixed_handle_position_ = start_selection_handle_->position() -
+                             gfx::Vector2dF(0, GetStartLineHeight() / 2.f);
+  }
+}
+
+void TouchSelectionController::OnHandleDragUpdate(const TouchHandle& handle,
+                                                  const gfx::PointF& position) {
+  // As the position corresponds to the bottom left point of the selection
+  // bound, offset it by half the corresponding line height.
+  float half_line_height = &handle == end_selection_handle_.get()
+                               ? GetEndLineHeight() / 2.f
+                               : GetStartLineHeight() / 2.f;
+  gfx::PointF line_position = position - gfx::Vector2dF(0, half_line_height);
+  if (&handle == insertion_handle_.get()) {
+    client_->MoveCaret(line_position);
+  } else {
+    client_->SelectBetweenCoordinates(fixed_handle_position_, line_position);
+  }
+}
+
+void TouchSelectionController::OnHandleDragEnd(const TouchHandle& handle) {
+}
+
+void TouchSelectionController::OnHandleTapped(const TouchHandle& handle) {
+  if (insertion_handle_ && &handle == insertion_handle_.get())
+    client_->OnSelectionEvent(INSERTION_TAPPED, GetStartPosition());
+}
+
+void TouchSelectionController::SetNeedsAnimate() {
+  client_->SetNeedsAnimate();
+}
+
+scoped_ptr<TouchHandleDrawable> TouchSelectionController::CreateDrawable() {
+  return client_->CreateDrawable();
+}
+
+void TouchSelectionController::OnInsertionChanged() {
+  DeactivateSelection();
+
+  if (!allow_automatic_insertion_activation_ || !selection_editable_)
+    return;
+
+  const bool was_active = is_insertion_active_;
+  const gfx::PointF position = GetStartPosition();
+  if (!is_insertion_active_)
+    ActivateInsertion();
+  else
+    client_->OnSelectionEvent(INSERTION_MOVED, position);
+
+  insertion_handle_->SetVisible(start_visible_, GetAnimationStyle(was_active));
+  insertion_handle_->SetPosition(position);
+}
+
+void TouchSelectionController::OnSelectionChanged() {
+  DeactivateInsertion();
+
+  if (!allow_automatic_selection_activation_)
+    return;
+
+  const bool was_active = is_selection_active_;
+  ActivateSelection();
+
+  const TouchHandle::AnimationStyle animation = GetAnimationStyle(was_active);
+  start_selection_handle_->SetVisible(start_visible_, animation);
+  end_selection_handle_->SetVisible(end_visible_, animation);
+
+  start_selection_handle_->SetPosition(GetStartPosition());
+  end_selection_handle_->SetPosition(GetEndPosition());
+}
+
+void TouchSelectionController::ActivateInsertion() {
+  DCHECK(!is_selection_active_);
+
+  if (!insertion_handle_)
+    insertion_handle_.reset(new TouchHandle(this, TOUCH_HANDLE_CENTER));
+
+  if (!is_insertion_active_) {
+    is_insertion_active_ = true;
+    insertion_handle_->SetEnabled(true);
+    client_->OnSelectionEvent(INSERTION_SHOWN, GetStartPosition());
+  }
+}
+
+void TouchSelectionController::DeactivateInsertion() {
+  if (!is_insertion_active_)
+    return;
+  DCHECK(insertion_handle_);
+  is_insertion_active_ = false;
+  insertion_handle_->SetEnabled(false);
+  client_->OnSelectionEvent(INSERTION_CLEARED, gfx::PointF());
+}
+
+void TouchSelectionController::ActivateSelection() {
+  DCHECK(!is_insertion_active_);
+
+  if (!start_selection_handle_)
+    start_selection_handle_.reset(new TouchHandle(this, start_orientation_));
+  else
+    start_selection_handle_->SetOrientation(start_orientation_);
+
+  if (!end_selection_handle_)
+    end_selection_handle_.reset(new TouchHandle(this, end_orientation_));
+  else
+    end_selection_handle_->SetOrientation(end_orientation_);
+
+  if (!is_selection_active_) {
+    is_selection_active_ = true;
+    start_selection_handle_->SetEnabled(true);
+    end_selection_handle_->SetEnabled(true);
+    client_->OnSelectionEvent(SELECTION_SHOWN, GetStartPosition());
+  }
+}
+
+void TouchSelectionController::DeactivateSelection() {
+  if (!is_selection_active_)
+    return;
+  DCHECK(start_selection_handle_);
+  DCHECK(end_selection_handle_);
+  start_selection_handle_->SetEnabled(false);
+  end_selection_handle_->SetEnabled(false);
+  is_selection_active_ = false;
+  client_->OnSelectionEvent(SELECTION_CLEARED, gfx::PointF());
+}
+
+void TouchSelectionController::ResetCachedValues() {
+  start_rect_ = gfx::RectF();
+  end_rect_ = gfx::RectF();
+  start_orientation_ = TOUCH_HANDLE_ORIENTATION_UNDEFINED;
+  end_orientation_ = TOUCH_HANDLE_ORIENTATION_UNDEFINED;
+  start_visible_ = false;
+  end_visible_ = false;
+  selection_editable_for_last_update_ = false;
+}
+
+gfx::PointF TouchSelectionController::GetStartPosition() const {
+  return start_rect_.bottom_left();
+}
+
+gfx::PointF TouchSelectionController::GetEndPosition() const {
+  return end_rect_.bottom_left();
+}
+
+float TouchSelectionController::GetStartLineHeight() const {
+  return start_rect_.height();
+}
+
+float TouchSelectionController::GetEndLineHeight() const {
+  return end_rect_.height();
+}
+
+TouchHandle::AnimationStyle
+TouchSelectionController::GetAnimationStyle(bool was_active) const {
+  return was_active && client_->SupportsAnimation()
+             ? TouchHandle::ANIMATION_SMOOTH
+             : TouchHandle::ANIMATION_NONE;
+}
+
+}  // namespace content